/usr/share/doc/xterm/xterm.faq.html is in xterm 297-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 4050 4051 4052 4053 4054 4055 4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 4086 4087 4088 4089 4090 4091 4092 4093 4094 4095 4096 4097 4098 4099 4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153 4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 4188 4189 4190 4191 4192 4193 4194 4195 4196 4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207 4208 4209 4210 4211 4212 4213 4214 4215 4216 4217 4218 4219 4220 4221 4222 4223 4224 4225 4226 4227 4228 4229 4230 4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249 4250 4251 4252 4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307 4308 4309 4310 4311 4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329 4330 4331 4332 4333 4334 4335 4336 4337 4338 4339 4340 4341 4342 4343 4344 4345 4346 4347 4348 4349 4350 4351 4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362 4363 4364 4365 4366 4367 4368 4369 4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462 4463 4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659 4660 4661 4662 4663 4664 4665 4666 4667 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678 4679 4680 4681 4682 4683 4684 4685 4686 4687 4688 4689 4690 4691 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710 4711 4712 4713 4714 4715 4716 4717 4718 4719 4720 4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849 4850 4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861 4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315 5316 5317 5318 5319 5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382 5383 5384 5385 5386 5387 5388 5389 5390 5391 5392 5393 5394 5395 5396 5397 5398 5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440 5441 5442 5443 5444 5445 5446 5447 5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461 5462 5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473 5474 5475 5476 5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533 5534 5535 5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573 5574 5575 5576 5577 5578 5579 5580 5581 5582 5583 5584 5585 5586 5587 5588 5589 5590 5591 5592 5593 5594 5595 5596 5597 5598 5599 5600 5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611 5612 5613 5614 5615 5616 5617 5618 5619 5620 5621 5622 5623 5624 5625 5626 5627 5628 5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658 5659 5660 5661 5662 5663 5664 5665 5666 5667 5668 5669 5670 5671 5672 5673 5674 5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695 5696 5697 5698 5699 5700 5701 5702 5703 5704 5705 5706 5707 5708 5709 5710 5711 5712 5713 5714 5715 5716 5717 5718 5719 5720 5721 5722 5723 5724 5725 5726 5727 5728 5729 5730 5731 5732 5733 5734 5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750 5751 5752 5753 5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765 5766 5767 5768 5769 5770 5771 5772 5773 5774 5775 5776 5777 5778 5779 5780 5781 5782 5783 5784 5785 5786 5787 5788 5789 5790 5791 5792 5793 5794 5795 5796 5797 5798 5799 5800 5801 5802 5803 5804 5805 5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816 5817 5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839 5840 5841 5842 5843 5844 5845 5846 5847 5848 5849 5850 5851 5852 5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864 5865 5866 5867 5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890 5891 5892 5893 5894 5895 5896 5897 5898 5899 5900 5901 5902 5903 5904 5905 5906 5907 5908 5909 5910 5911 5912 5913 5914 5915 5916 5917 5918 5919 5920 5921 5922 5923 5924 5925 5926 5927 5928 5929 5930 5931 5932 5933 5934 5935 5936 5937 5938 5939 5940 5941 5942 5943 5944 5945 5946 5947 5948 5949 5950 5951 5952 5953 5954 5955 5956 5957 5958 5959 5960 5961 5962 5963 5964 5965 5966 5967 5968 5969 5970 5971 5972 5973 5974 5975 5976 5977 5978 5979 5980 5981 5982 5983 5984 5985 5986 5987 5988 5989 5990 5991 5992 5993 5994 5995 5996 5997 5998 5999 6000 6001 6002 6003 6004 6005 6006 6007 6008 6009 6010 6011 6012 6013 6014 6015 6016 6017 6018 6019 6020 6021 6022 6023 6024 6025 6026 6027 6028 6029 6030 6031 6032 6033 6034 6035 6036 6037 6038 6039 6040 6041 6042 6043 6044 6045 6046 6047 6048 6049 6050 6051 6052 6053 6054 6055 6056 6057 6058 6059 6060 6061 6062 6063 6064 6065 6066 6067 6068 6069 6070 6071 6072 6073 6074 6075 6076 6077 6078 6079 6080 6081 6082 6083 6084 6085 6086 6087 6088 6089 6090 6091 6092 6093 6094 6095 6096 6097 6098 6099 6100 6101 6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113 6114 6115 6116 6117 6118 6119 6120 6121 6122 6123 6124 6125 6126 6127 6128 6129 6130 6131 6132 6133 6134 6135 6136 6137 6138 6139 6140 6141 6142 6143 6144 6145 6146 6147 6148 6149 6150 6151 6152 6153 6154 6155 6156 6157 6158 6159 6160 6161 6162 6163 6164 6165 6166 6167 6168 6169 6170 6171 6172 6173 6174 6175 6176 6177 6178 6179 6180 6181 6182 6183 6184 6185 | <!--
*****************************************************************************
* Copyright 1997-2012,2013 by Thomas E. Dickey *
* All Rights Reserved. *
* *
* Permission to use, copy, modify, and distribute this software and its *
* documentation for any purpose and without fee is hereby granted, provided *
* that the above copyright notice appear in all copies and that both that *
* copyright notice and this permission notice appear in supporting *
* documentation, and that the name of the above listed copyright holder(s) *
* not be used in advertising or publicity pertaining to distribution of the *
* software without specific, written prior permission. *
* *
* THE ABOVE LISTED COPYRIGHT HOLDER(S) DISCLAIM ALL WARRANTIES WITH REGARD *
* TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND *
* FITNESS, IN NO EVENT SHALL THE ABOVE LISTED COPYRIGHT HOLDER(S) BE LIABLE *
* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES *
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN *
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF *
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. *
*****************************************************************************
$XTermId: xterm.faq.html,v 1.243 2013/07/05 17:33:01 tom Exp $
-->
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
<html>
<head>
<base href="http://invisible-island.net/xterm/">
<meta name="generator" content=
"HTML Tidy for Linux (vers 25 March 2009), see www.w3.org">
<title>XTerm – Frequently Asked Questions (FAQ)</title>
<link rev="MADE" href="mailto:dickey@invisible-island.net">
<meta http-equiv="Content-Type" content=
"text/html; charset=us-ascii">
<link rel="SHORTCUT ICON" href="/img/icons/xterm.ico" type=
"image/x-icon">
<link rel="stylesheet" href="/css/simplestyle.css" type=
"text/css">
<link rel="stylesheet" href="/css/inline-code.css" type=
"text/css">
<link rel="stylesheet" href="/css/xterm-icons.css" type=
"text/css">
<style type="text/css">
@import "/css/simplenav15.css" all;
</style>
</head>
<body>
<hr>
<p><a href="../">http://invisible-island.net/</a><a href=
"./">xterm/</a><br>
Copyright © 1997-2012,2013 by Thomas E. Dickey</p>
<hr>
<p><a href="xterm.faq.html">Here</a> is the latest version of
this file.</p>
<div class="nav">
<ul>
<li><a href="xterm.faq.html">(top)</a></li>
<li><a href="xterm.faq.html#what_is_it">What is
<strong>XTerm</strong>?</a></li>
<li><a href="xterm.faq.html#who_did_it">Who wrote
<strong>XTerm</strong>?</a></li>
<li><a href="xterm.faq.html#what_is_vt220">What is a
VT220?</a></li>
<li><a href="xterm.faq.html#what_platforms">What platforms
does it run on?</a></li>
<li><a href="xterm.faq.html#latest_version">What is the
latest version?</a></li>
<li><a href="xterm.faq.html#other_versions">What versions are
available?</a></li>
<li><a href="xterm.faq.html#compare_versions">Comparing
versions, by counting controls</a></li>
<li><a href="xterm.faq.html#how_do_i">How do I ...</a></li>
<li><a href="xterm.faq.html#frequent_problems">Frequent
problems</a></li>
<li><a href="xterm.faq.html#known_bugs">Known Bugs in
<strong>XTerm</strong> and Look–alikes</a></li>
<li><a href="xterm.faq.html#building_it">How do I build
<strong>XTerm</strong>?</a></li>
<li><a href="xterm.faq.html#report_bugs">How do I report
bugs?</a></li>
<li><a href="xterm.faq.html#more_info">Additional
Information</a></li>
<li><a href="xterm.faq.html#future_work">Ongoing/future
work</a></li>
</ul>
</div>
<h2 id="what_is_it-id"><a name="what_is_it" id="what_is_it">What
is <strong>XTerm</strong>?</a></h2>
<p>From the manual page:</p>
<blockquote>
<p>The xterm program is a terminal emulator for the X Window
System. It provides DEC VT102/VT220 and selected features from
higher-level terminals such as VT320/VT420/VT520 (VTxxx). It
also provides Tektronix 4014 emulation for programs that cannot
use the window system directly. If the underlying operating
system supports terminal resizing capabilities (for example,
the SIGWINCH signal in systems derived from 4.3bsd), xterm will
use the facilities to notify programs running in the window
whenever it is resized.</p>
</blockquote>
<p>That is, xterm (pronounced "<em>eks</em>-xterm") is a
<em>specific</em> program, not a generic item. It is the standard
X terminal emulator program.</p>
<p>This FAQ presents various useful bits of information for both
the specific program as well as other programs that imitate
it.</p>
<p>As a stylistic convention, the capitalized form is
"<em>XTerm</em>", which corresponds to the X resource class name.
Similarly, <em>uxterm</em> becomes "<em>UXTerm</em>".</p>
<h2 id="who_did_it-id"><a name="who_did_it" id="who_did_it">Who
wrote <strong>XTerm</strong>?</a></h2>
<p>I've been working on xterm since early 1996 (see my <a href=
"xterm.log.html">changelog</a> for details).</p>
<p>But the program is much older than that.</p>
<h3 id="pre_history-id"><a name="prehistory" id="prehistory">A
Prehistory Perspective</a></h3>
<p>A lot of people, cited at the bottom of the manual page wrote
the original xterm program, maintained by the X Consortium (later
part of the Open Group – I'm well aware of the distinction,
but am citing when the work was done, not who the current owner
may be). There is no changelog, and it is not clear who did what.
Email from Jim Gettys provides some background:</p>
<blockquote>
<p>Cast of thousands...</p>
<p>To give a bit of history, xterm predates X!</p>
<p>It was originally written as a stand-alone terminal emulator
for the VS100 by Mark Vandevoorde, as my coop student the
summer that X started.</p>
<p>Part way through the summer, it became clear that X was more
useful than trying to do a stand alone program, so I had him
retarget it to X. Part of why xterm's internals are so
horrifying is that it was originally intended that a single
process be able to drive multiple VS100 displays. Don't hold
this against Mark; it isn't his fault.</p>
<p>I then did a lot of hacking on it, and merged several
improved versions from others back in.</p>
<p>Notable improvements include the proper ANSI parser, that
Bob McNamara did.</p>
<p>The Tek 4010 support came from a guy at Smithsonian
Astrophysical Observatory whose name slips my mind at the
moment.</p>
<p>Ported to X11 by Loretta Guarino.</p>
<p>Then hacked on at the X Consortium by uncounted people.</p>
</blockquote>
<p>Email from Doug Mink provides more background:</p>
<blockquote>
<p>I was checking out the newly revised AltaVista search engine
to see what was on the net about xterm, and I found your pages.
I can add to the FAQ in that I was the "guy at the Smithsonian
Astrophysical Observatory" Jim Gettys refers to. I am listed at
the end of the man page under authors. What happened was that I
was hired by SAO (after leaving the research staff at MIT) in
October 1985 to write analysis software for the Spacelab 2
Infrared Telescope which was to fly on the Space Shuttle in
1985 less than six months after I was hired. I came with a tar
tape full of software I had written for Unix and Tektronix
terminals, but I was presented with a VS100 terminal which had
an early version (X6 or so) of xterm, with no graphics
capabilities. SAO is at Harvard, across Cambridge from MIT,
where Jim Gettys was detailed from DEC to the X project, and
Jim had connections with SAO, having worked here after college
(MIT, where we had both worked at the observatory at various
times); he was still sharing an apartment with an SAO colleague
of mine, too. Anyway, everyone decided that since I knew
Tektronix commands pretty well, and our group desparately
needed the graphics capabilities, it would be a good use of my
time to implement a Tektronix terminal emulator under X. So I
set to work learning more C--I had only written a couple of
wrappers to C I/O routines so I could use them with my Fortran
software--and wrote a Tektronix emulator. The only X
documentation at the time was the code itself. While I was at
it, I wrote an improved Tektronix emulator for our Imagen laser
printer which used the full resolution of that 300 dpi printer
instead of the effective 100 dpi (i.e. jaggy) emultator
distributed with the printer. The original xterm Tek emulator
shared a window with the VT100 emulator, much like on the VT240
terminals which I had been using at MIT before I came to
Harvard. With a VAX 750 running several VS100's, window
creation was sloowww, so sharing a window was the quickest way
to do things, and all of my software was written for that mode
of operation, anyway. While I wrote the emulator so that my
software would work on it, it was tested by the X group against
a BBN graphics package, the name of which slips my mind right
now.</p>
<p>Anyway, 15 years later, I am still using xterm and some of
the same mapping software I wrote the emulator for. And I am
still at the Smithsonian Astrophysical Observatory.</p>
</blockquote>
<h3 id="my_history-id"><a name="my_history" id="my_history">My
Involvement</a></h3>
<p>My involvement with <strong>xterm</strong> through XFree86
began at the <a href="xterm.html#history">end of 1995</a>. This
website has been "here" since 2001/6/5, replacing my ClarkNet
page. I started the ClarkNet page 1996/12/31, as a followup to
the <a href=
"http://invisible-island.net/ncurses/ncurses-license.html#patch_961224">
release of ncurses 4.0</a>) which featured xterm as one of the 16
programs I was involved with. From the outset, the page provided
a link to a snapshot of the current source. Copies of patches
which I sent to XFree86 were available on the ftp area.</p>
<p>XFree86 had its sources in CVS, but (like others in that era),
were not directly visible to random developers. That came later.
I started by downloading the sources (30Mb of compressed
tar-files on a 56Kb phone connection took about 6 hours) and
updating them with patches from the XFree86 mailing list.</p>
<p>Like the other programs that I worked on with others (<a href=
"http://invisible-island.net/vile/vile.html">vile</a>, <a href=
"http://invisible-island.net/tin/tin.html">tin</a>, <a href=
"http://invisible-island.net/lynx/lynx.html">lynx</a>), I set up
an RCS archive to track my changes locally before sending patches
to the development list. As the XFree86 developers issued new
patches, I would re-synchronize my archive. Later, XFree86
provided CVS (initially readonly). I was granted commit
privileges on this <a href=
"http://invisible-island.net/ansification/ansify-xfs-cve.html#xfree86_work">
in November 2000</a>.</p>
<p>Throughout this period, my work on <strong>xterm</strong> was
released as part of XFree86. It was rare for a separate package
to be provided. That was due to the potential conflict between
the install procedures. Users of the downloads from my web/ftp
site were predominantly individual developers.</p>
<p>There were exceptions. Christian Weisgerber proposed a package
for FreeBSD ports later in 1999 (<a href=
"http://www.mavetju.org/mail/view_message.php?list=freebsd-ports&id=578273">ports/15545:
new port: x11/xterm</a>, followup in <a href=
"http://marc.info/?t=102422536300028&r=l&=2">March
2000</a>). However, that was an exception. None of the Linux
distributions provided a separate package before 2003 (when Mike
Harris created a package of <a href=
"xterm.log.html#xterm_177">patch #177</a> for Red Hat). Again
that is more of an exception than a rule:</p>
<ul>
<li>SuSE's package began October 23, 2004 with <a href=
"xterm.log.html#xterm_196">patch #196</a>.</li>
<li>Mandriva's package began October 22, 2005 with <a href=
"xterm.log.html#xterm_205">patch #205</a>.</li>
<li>The Debian package for xterm began in January 6, 2006 with
<a href="xterm.log.html#xterm_204">patch #204</a>.</li>
</ul>
<p>Given that context (sources distributed via XFree86 CVS,
releases via XFree86), the statement made by an Xorg hacker
<a href=
"http://lists.freedesktop.org/archives/xorg/2005-January/005847.html">
early in 2005</a> asserting that "It has not been maintained by
anyone within the XFree86 or X.org trees for many years" was at
best misleading.</p>
<p>After the "<a href=
"xterm.faq.html#xterm-xorg">fork</a>" (sic) of Xorg in 2004,
I continued to commit changes for xterm in <a href=
"http://cvsweb.xfree86.org/cvsweb/xc/programs/xterm/">XFree86
CVS</a> until <a href="xterm.log.html#xterm_216">patch #216</a>
in mid-2006. I stopped at that point because it was not possible
to incorporate changes into xterm which were not sent to me
first. I still send patch announcements to both the XFree86 and
Xorg mailing lists, of course.</p>
<h3 id="forward_history-id"><a name="forward_history" id=
"forward_history">Focus of this FAQ</a></h3>
<p>This FAQ is oriented toward the version of xterm originally
distributed with XFree86 (more commonly known as modern, or "new
xterm", with a corresponding terminal description "xterm-new"),
which was based on the X11R6.3 xterm, with the addition of ANSI
color and VT220 controls.</p>
<h2 id="what_is_vt220-id"><a name="what_is_vt220" id=
"what_is_vt220">What is a VT220?</a></h2>
<h3 id="why_vt220-id"><a name="what_vt220" id="what_vt220">Why a
VT220?</a></h3>
<p>The manual page mentions a VT220. Most terminal emulators
documentation talk about VT100. But a VT100 is a rather limited
subset of what people expect:</p>
<ul>
<li>VT100s have no function keys. Arguably, PF1-PF4 are
function keys. My keyboard has 12 function keys.</li>
<li>VT100s do not do <a href=
"../ncurses/ncurses.faq.html">color</a>.</li>
</ul>
<p>Initially, I was only interested in making colors workable for
curses programs.</p>
<p>Later, I noticed that xterm had some support for what would
now be termed as ISO-2022. That was a VT220 feature, rather than
VT100. There were some missing pieces. So I decided to fill in
those pieces and make xterm a VT220 emulator. (VT220s do not do
ANSI color either—the missing pieces were in other
areas).</p>
<p><strong>XTerm</strong> also provides features that are in
neither VT100 nor VT220, which are used by other programs as
"xterm emulation".</p>
<ul>
<li>set (and retrieve) window- and icon-labels using escape
sequences.</li>
<li>interpret mouse clicks as escape sequences that can be read
by a program.</li>
</ul>
<p>By the way, the control string used for setting the titles was
not in a standard format:</p>
<ul>
<li>In X10 (1988), the string was simply terminated by any
nonprinting character.</li>
<li>X11R4 (1989) modified that to ensure that the nonprinting
character is an ASCII BEL (control/G).</li>
<li>There is no explanation in the (sketchy) notes distributed
with the X11R4 xterm; in retrospect it seems that the most
likely explanation for the choice is that it was simpler to
implement in shell scripts than <code>ESC \</code>.</li>
</ul>
<p>I revised that area <a href="xterm.log.html#xterm_24">starting
in 1996</a>,</p>
<ul>
<li>first to use xterm's state table for handling the input,
and then</li>
<li>to accept the standard string terminator as well.</li>
</ul>
<h3 id="whatis_state_table">What is a State Table?</h3>
<p>That was mentioned regarding the title strings.
<strong>XTerm</strong> uses a state machine to handle incoming
characters. That is essentially what a real terminal does. Other
"xterm" terminal emulators typically do not do this, which makes
them not do well with <a href=
"../vttest/vttest.html">vttest</a>.</p>
<h2 id="what_platforms-id"><a name="what_platforms" id=
"what_platforms">What platforms does it run on?</a></h2>
<p><strong>XTerm</strong> runs in all of the implementations of
X11. I've built and run these since I started working on
xterm:</p>
<ul>
<li>AIX 3.2.5, 4.1, 4.3 (cc)</li>
<li>Digital Unix 3.2, 4.0, 5.0 (cc)</li>
<li>FreeBSD 2.2.6 to 6.0 (gcc 2.8)</li>
<li>HP-UX 9.05 to 11.23 (gcc 2.7.2 to 3.4)</li>
<li>IRIX 5.2, 6.2 (cc, gcc 2.7.2, gcc 2.8)</li>
<li>Linux 2.0.0 to 2.6.26 (gcc 2.7.2 to 4.3)</li>
<li>SCO OpenServer 5 (cc, gcc).</li>
<li>Solaris 2.4, 2.5, 2.5.1, 2.6, 7, 8 (cc, gcc 2.7.2)</li>
<li>SunOS 4.1.1, 4.1.3 (gcc 2.7.2)</li>
</ul>
<p>The older configurations have X11R5 libraries. Only minor
changes are needed to make xterm work on those systems. However,
with X11R6 you can obtain better locale support, as well as new
features such as the active icon. X11R7... not much to say
there.</p>
<h2 id="latest_version-id"><a name="latest_version" id=
"latest_version">What is the latest version?</a></h2>
<p>The most recent (and well supported) version of xterm is the
one that I maintain:</p>
<ul>
<li><a href=
"ftp://invisible-island.net/xterm/xterm.tar.gz">current source
(ftp)</a></li>
<li><a href=
"http://invisible-island.net/datafiles/release/xterm.tar.gz">current
source (http)</a></li>
</ul>
<h2 id="other_versions-id"><a name="other_versions" id=
"other_versions">What versions are available?</a></h2>
<p>There are several other versions of xterm, based on xterm's
source. These include</p>
<ul>
<li><a href="xterm.faq.html#bug_ansi_xterm">ansi_xterm</a></li>
<li><a href=
"xterm.faq.html#bug_color_xterm">color_xterm</a></li>
<li><a href="xterm.faq.html#bug_cxterm">cxterm</a>
(Chinese)</li>
<li><a href="xterm.faq.html#bug_hanterm">hanterm</a>
(Korean)</li>
<li><a href="xterm.faq.html#bug_mxterm">mxterm</a></li>
<li><a href="xterm.faq.html#bug_nxterm">nxterm</a></li>
<li><a href="xterm.faq.html#bug_kterm">kterm</a>
(Japanese)</li>
<li><a href="xterm.faq.html#bug_xterm_r6">xterm</a> (from X
Consortium)</li>
</ul>
<p>There are similar programs not based on xterm's source, which
are compatible to different degrees. These include</p>
<ul>
<li><a href="xterm.faq.html#bug_dtterm">dtterm</a></li>
<li><a href="xterm.faq.html#bug_emu">emu</a> (from X
Consortium)</li>
<li><a href="xterm.faq.html#bug_eterm">Eterm</a></li>
<li><a href="xterm.faq.html#bug_gnometerm">GNOME
Terminal</a></li>
<li><a href="xterm.faq.html#bug_multignome">Multi GNOME
Terminal (MGT)</a></li>
<li><a href="xterm.faq.html#bug_mterm">mterm</a></li>
<li><a href="xterm.faq.html#bug_konsole">konsole</a></li>
<li><a href="xterm.faq.html#bug_mlterm">mlterm</a> (Multi
Lingual)</li>
<li><a href="xterm.faq.html#bug_osso_xterm">osso-xterm</a></li>
<li><a href="xterm.faq.html#bug_roxterm">roxterm</a></li>
<li><a href="xterm.faq.html#bug_rxvt">rxvt</a></li>
<li><a href="xterm.faq.html#bug_st">st</a></li>
<li><a href="xterm.faq.html#bug_xfce_term">xfce-term</a></li>
<li><a href="xterm.faq.html#bug_xgterm">xgterm</a></li>
<li><a href="xterm.faq.html#bug_xiterm">xiterm</a></li>
</ul>
<p>Some of these use the <a href="xterm.faq.html#vte_widget">VTE
widget</a>. Since that supplies most of the terminal emulation,
the remaining differences between programs using VTE tend to be
at the level of the window manager (menus, borders, etc.). Other
(older) programs which are based on reusable widgets include
<a href="xterm.faq.html#bug_dtterm">dtterm</a> and <a href=
"xterm.faq.html#bug_emu">emu</a>.</p>
<p>(I am aware of a few others, such as <strong>xcterm</strong>,
but have not seen a working version of these).</p>
<p>Finally of course, there are a multitude of programs which set
TERM to "xterm", in the hope that applications will treat them
the same as xterm. For example, PuTTY does this. But its wrapping
behavior is incompatible with xterm (and any vt100 emulator). You
can see this in the first menu entry for <a href=
"../vttest/vttest.html">vttest</a>.</p>
<p>Each of the programs noted here which are well-established and
which are known to differ markedly from xterm have their own
terminal descriptions in ncurses, to which TERM should be set.
Otherwise, bug-reports are misdirected to ncurses which should
have been addressed by the respective developers of these
programs. <a href=
"../ncurses/ncurses.html#download_database">ncurses</a>. These
include</p>
<ul>
<li>Eterm</li>
<li>gnome (obsolete)</li>
<li>konsole</li>
<li>mlterm</li>
<li>mrxvt</li>
<li>putty</li>
<li>rxvt</li>
<li>vte (preferred)</li>
</ul>
<h2 id="compare_versions-id"><a name="compare_versions" id=
"compare_versions">Comparing versions, by counting
controls</a></h2>
<p>Several of these programs are claimed (either by their
developers, or their users) to emulate "most" of xterm. To me,
"most" would be something quantifiable, e.g., 80 percent. To
satisfy my curiousity, I wrote a script to extract the control
sequence information from <a href=
"xterm.faq.html#ctlseqs_ms">ctlseqs.txt</a>. This counts each
control sequence, as well as the variations such as setting bold,
color, inverse video. Then I (laboriously) inspected these
terminal implementations:</p>
<ul>
<li>xterm patch #266 ("xterm-new")</li>
<li>X11R6.3 xterm (xterm-r6)</li>
<li>DEC vt220</li>
<li>DEC vt102</li>
<li>rxvt 2.7.10</li>
<li>rxvt-unicode 9.09 (urxvt)</li>
<li>konsole 2.5.3</li>
<li>VTE 0.25.91 (vte), used in GNOME-Terminal and kindred.</li>
</ul>
<p>As of mid-November 2010, these are the latest implementations.
I included data for the vt220 and vt102 to be able to contrast
the various terminal <em>emulators</em> against those as well as
xterm. There are:</p>
<ul>
<li>498 control sequences listed in the corresponding file for
xterm patch #266.</li>
<li>192 of those are "primary", e.g., disregarding parameters
such as those distinguishing bold from color.</li>
<li>37 of the primary control sequences have secondary
sequences.</li>
</ul>
<p>For each control, there are three possibilities:</p>
<ol>
<li>"yes" — the terminal implements it, matching xterm.
If xterm implements it, and it is a feature of vt220 or vt102,
then in turn xterm's behavior must match vt220 or vt102.</li>
<li>"partial" — the terminal implements it, but its
behavior does not match the reference noted above.</li>
<li>"no" — the terminal does not implement the
control.</li>
</ol>
<p>The control sequences document lists a few controls which
xterm does not (completely) implement, e.g.,</p>
<ul>
<li>key-repeat</li>
<li>enabling LEDs other than scroll-lock</li>
</ul>
<p>None of the other terminal emulators implements those
either.<br></p>
<table border="1" summary=
"Comparing against the control sequences document">
<caption>
Comparing against the control sequences document
</caption>
<colgroup>
<col width="15%">
<col width="15%">
<col width="15%">
<col width="35%">
</colgroup>
<tr>
<th>yes</th>
<th>partial</th>
<th>no</th>
<th>program</th>
</tr>
<tr>
<td>488</td>
<td>4</td>
<td>6</td>
<td>xterm-new</td>
</tr>
<tr>
<td>154</td>
<td>6</td>
<td>338</td>
<td>xterm-r6</td>
</tr>
<tr>
<td>188</td>
<td>5</td>
<td>305</td>
<td>vt220</td>
</tr>
<tr>
<td>104</td>
<td>0</td>
<td>394</td>
<td>vt102</td>
</tr>
<tr>
<td>204</td>
<td>3</td>
<td>291</td>
<td>rxvt</td>
</tr>
<tr>
<td>219</td>
<td>3</td>
<td>276</td>
<td>urxvt</td>
</tr>
<tr>
<td>191</td>
<td>2</td>
<td>305</td>
<td>putty</td>
</tr>
<tr>
<td>170</td>
<td>3</td>
<td>325</td>
<td>konsole</td>
</tr>
<tr>
<td>184</td>
<td>6</td>
<td>308</td>
<td>vte</td>
</tr>
</table>
<p>Modern xterm implements 188 primary controls. In this table,
konsole ranks last because it does not support vt52 emulation.
This is not unusual, since the rxvt-based emulators do not,
either. However, all vt100's provide this feature; programs
lacking this are not really a vt100 emulator. On the other hand,
PuTTY (which is not a vt100 emulator due to its incompatible
wrapping behavior) supports this feature.</p>
<p>Aside from that, the various emulators implement much the same
features from xterm. None implements as many as half of xterm's
controls.</p>
<table border="1" summary="Comparing against xterm">
<caption>
Comparing against xterm
</caption>
<colgroup>
<col width="15%">
<col width="15%">
<col width="15%">
<col width="35%">
</colgroup>
<tr>
<th>yes</th>
<th>partial</th>
<th>no</th>
<th>program</th>
</tr>
<tr>
<td>488</td>
<td>0</td>
<td>0</td>
<td>xterm-new</td>
</tr>
<tr>
<td>154</td>
<td>6</td>
<td>328</td>
<td>xterm-r6</td>
</tr>
<tr>
<td>182</td>
<td>2</td>
<td>304</td>
<td>vt220</td>
</tr>
<tr>
<td>98</td>
<td>0</td>
<td>390</td>
<td>vt102</td>
</tr>
<tr>
<td>204</td>
<td>3</td>
<td>281</td>
<td>rxvt</td>
</tr>
<tr>
<td>219</td>
<td>3</td>
<td>266</td>
<td>urxvt</td>
</tr>
<tr>
<td>189</td>
<td>2</td>
<td>297</td>
<td>putty</td>
</tr>
<tr>
<td>170</td>
<td>3</td>
<td>315</td>
<td>konsole</td>
</tr>
<tr>
<td>184</td>
<td>6</td>
<td>298</td>
<td>vte</td>
</tr>
</table>
<p>DEC VT220 implements 96 primary controls. Modern xterm (as
documented), implements most of the VT220. VTE implements fewer
than half. The others are a little better. None of the others
could be used as a real VT220.</p>
<table border="1" summary="Comparing against vt220">
<caption>
Comparing against vt220
</caption>
<colgroup>
<col width="15%">
<col width="15%">
<col width="15%">
<col width="35%">
</colgroup>
<tr>
<th>yes</th>
<th>partial</th>
<th>no</th>
<th>program</th>
</tr>
<tr>
<td>182</td>
<td>0</td>
<td>6</td>
<td>xterm-new</td>
</tr>
<tr>
<td>78</td>
<td>6</td>
<td>104</td>
<td>xterm-r6</td>
</tr>
<tr>
<td>188</td>
<td>0</td>
<td>0</td>
<td>vt220</td>
</tr>
<tr>
<td>104</td>
<td>0</td>
<td>84</td>
<td>vt102</td>
</tr>
<tr>
<td>101</td>
<td>3</td>
<td>84</td>
<td>rxvt</td>
</tr>
<tr>
<td>106</td>
<td>3</td>
<td>79</td>
<td>urxvt</td>
</tr>
<tr>
<td>107</td>
<td>2</td>
<td>79</td>
<td>putty</td>
</tr>
<tr>
<td>100</td>
<td>3</td>
<td>85</td>
<td>konsole</td>
</tr>
<tr>
<td>88</td>
<td>6</td>
<td>94</td>
<td>vte</td>
</tr>
</table>
<p>DEC VT102 (the actual flavor used for "vt100" in most cases),
implements 68 primary controls. Again, VTE fares worst, and the
others a little better.</p>
<table border="1" summary="Comparing against vt102">
<caption>
Comparing against vt102
</caption>
<colgroup>
<col width="15%">
<col width="15%">
<col width="15%">
<col width="35%">
</colgroup>
<tr>
<th>yes</th>
<th>partial</th>
<th>no</th>
<th>program</th>
</tr>
<tr>
<td>98</td>
<td>0</td>
<td>6</td>
<td>xterm-new</td>
</tr>
<tr>
<td>70</td>
<td>6</td>
<td>28</td>
<td>xterm-r6</td>
</tr>
<tr>
<td>104</td>
<td>0</td>
<td>0</td>
<td>vt220</td>
</tr>
<tr>
<td>104</td>
<td>0</td>
<td>0</td>
<td>vt102</td>
</tr>
<tr>
<td>79</td>
<td>2</td>
<td>23</td>
<td>rxvt</td>
</tr>
<tr>
<td>81</td>
<td>2</td>
<td>21</td>
<td>urxvt</td>
</tr>
<tr>
<td>86</td>
<td>2</td>
<td>16</td>
<td>putty</td>
</tr>
<tr>
<td>85</td>
<td>3</td>
<td>16</td>
<td>konsole</td>
</tr>
<tr>
<td>60</td>
<td>1</td>
<td>43</td>
<td>vte</td>
</tr>
</table>
<p>In summary, none of the other terminal emulators emulates
"most" of xterm. Instead, they implement the most commonly-used
control sequences, and there are differences between them.</p>
<h2 id="how_do_i-id"><a name="how_do_i" id="how_do_i">How do I
...</a></h2>
<p>Not really problems, but frequently asked questions (the point
of this, after all):</p>
<ul>
<li><a href="xterm.faq.html#how2_fsize">How do I change the
font size?</a></li>
<li><a href="xterm.faq.html#how2_print">How do I print the
screen?</a></li>
<li><a href="xterm.faq.html#how2_fkeys">How do I set up
function keys?</a></li>
<li><a href="xterm.faq.html#how2_title">How do I set the
title?</a></li>
<li><a href="xterm.faq.html#how2_blink">How do I make the
cursor blink?</a></li>
</ul>
<h3 id="how2_fsize-id"><a name="how2_fsize" id="how2_fsize">How
do I change the font size?</a></h3>
<p><strong>XTerm</strong> uses fonts given as resource settings.
You can switch between these fonts at runtime, using a menu. This
is documented in the manpage, in the <a href=
"manpage/xterm.html#MENUS">MENUS</a> section.</p>
<p>X Consortium xterm provides popup menus, by pressing the
control key together with the mouse button. Control right mouse
button pops up the <em>VT FONTS</em> menu, from which you can
select fonts that are specified in xterm's resources. Usually
these are in increasing order of size.</p>
<p>Modern xterm provides the menu, plus a feature adapted from
rxvt: pressing the shifted keypad plus or minus keys steps
through the font menu selections, in order of their size.</p>
<p><strong>XTerm</strong>'s manpage does not document the syntax
for X resources; it is done in the X documentation. If you are
instead asking about a <a href=
"xterm.faq.html#utf8_fonts">problem displaying a given font</a>,
it may be due to a problem with your resource settings.</p>
<h3 id="how2_print-id"><a name="how2_print" id="how2_print">How
do I print the screen?</a></h3>
<p>That depends on why you want to print it.</p>
<p>If you want a trace of an interactive session, you should use
the <em>script</em> program. It records every character sent to
the screen, recording them in a file <code>typescript</code>.
There are two drawbacks to this approach:</p>
<ul>
<li>Every character is recorded. Even cursor movement, if you
run an editor.</li>
<li>You must start a new shell to capture the
<code>typescript</code> file.</li>
</ul>
<p>Well, what about logging? Some versions of xterm support
logging to a file. In fact modern xterm does. Logging was dropped
from X Consortium xterm during X11R5 due to security concerns.
Those were addressed, but logging was not reinstated (in fact
there is a related <a href="xterm.faq.html#bug_xterm_r6">bug</a>
in xterm). Some people prefer this, because it is convenient: you
can start and stop logging a popup menu entry. However</p>
<ul>
<li>Every character is recorded. Even cursor movement, if you
run an editor.</li>
<li>Line drawing characters are translated to control
characters, i.e., codes 0-31 (this may be fixed sometime, it is
a problem inherited from X Consortium xterm).</li>
</ul>
<p>Both <em>script</em> and logging are useful for recording, but
they require interpretation to make sense of the trace. You
probably would not send that trace to a printer (not twice,
anyway).</p>
<p>If you want to print the contents of the screen, modern xterm
implements, as part of the VT100 emulation, an "attached"
printer.</p>
<ul>
<li>The printer is really a pipe command, to which xterm
writes.</li>
<li>You can print the current line, page, or continuously with
the corresponding control sequences. That takes an application
program which knows how to print the screen.</li>
<li>If you do not have an application, xterm has a popup menu
entry to print the window.</li>
</ul>
<p>There are limitations and tradeoffs using the "attached"
printer, because it is an emulation:</p>
<ul>
<li>The emulation is based on detailed documentation for a
VT320. This states that control sequences are sent in each line
to reset bold, underlining and other printable attributes, and
to set them as needed. Your printer probably does not
understand this sort of input. Use the xterm resource
<code>printAttributes</code> to get more easily printed
output.</li>
<li>The printer may hang. Not really, but it seems that way. If
you use the "attached" printer from an application designed for
the VT100 terminal, it is written with the assumption that the
printer is a dedicated piece of hardware, printing onto a
continuous form. Use the <code>printerAutoClose</code> resource
to change xterm's behavior to close the printer pipe whenever
the terminal is told to switch the printer offline.</li>
</ul>
<p>If you use the popup menu to print the screen, this will close
the printer pipe unless it was already opened by the application
running in xterm.</p>
<h3 id="how2_fkeys-id"><a name="how2_fkeys" id="how2_fkeys">How
do I set up function keys?</a></h3>
<p>With modern xterm, this is relatively simple. So I'll answer
that first.</p>
<p>With X Consortium xterm, you had partial support for DEC VTxxx
function keys. Function keys F1 to F12 correspond to DEC's F1 to
F12 (sort of). Actually, DEC's VT220 terminals do not have codes
for F1 through F5. They are reserved for local functions. And the
VT220 (and up) terminals have 20 function keys. So you cannot do
anything with the F13 through F20 (i.e., DO, HELP and SELECT).
Finally, though xterm is reputed to be VT100-compatible, it has
no support for the VT100 keypad (PF1 to PF4, and the ","
key).</p>
<p>Modern (XFree86) xterm changed the X Consortium codes for F1
to F4 to match the VT100 PF1 to PF4, except when the emulation
level is VT220 and up. In this case, it generates the same F1 to
F4 codes as X Consortium xterm. Moreover, it adds a new resource
<code>sunKeyboard</code>, which tells the program whether it has
only 12 function keys (i.e., a Sun or PC keyboard). If so (this
is selectable from the popup menu), you can use the control key
with F1 to F12 to get F13 to F24, and use the "+" key on the
keypad as an alias for "," (comma).</p>
<p>The emulation level for modern xterm is set via the resource
<code>decTerminalID</code>, e.g., to 220 for a VT220. Once set,
applications can set the emulation level up or down within that
limit. DEC's terminals are configured in much the same way by a
setup option.</p>
<p>That is the simple way, using a couple of new resources. The
traditional way to get function keys involves translations. I
have seen a few postings on the newsgroups that do this. Here is
one from Bruce Momjian <root@candle.pha.pa.us> for a
VT220:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
xterm <span class=
"ident2">$XTERMFLAGS</span> +rw +sb +ls <span class="ident2">$@</span> -tm <span class="literal">'erase ^? intr ^c'</span> \<br>
-name vt220 -title vt220 -tn xterm-220 <span class="literal">"$@"</span> &<br>
<!--atr2html}}--></p>
</blockquote>
<p>with the corresponding resources:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">translations</span>:<span class=
"literal"> #override \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Home: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">3</span><span class="literal">~") \n \<br>
</span><span class="keyword"><Key></span><span class="literal">End: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">4</span><span class="literal">~") \n</span><br>
<span class="ident2">vt220</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">translations</span>:<span class=
"literal"> #override \n\<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F1: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("OP") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F2: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("OQ") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F3: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("OR") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F4: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("OS") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F5: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">16</span><span class="literal">~") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F6: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">17</span><span class="literal">~") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F7: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">18</span><span class="literal">~") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F8: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">19</span><span class="literal">~") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F9: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">20</span><span class="literal">~") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F10: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">21</span><span class="literal">~") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F11: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">28</span><span class="literal">~") \n \<br>
~Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F12: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">29</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F1: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">23</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F2: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">24</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F3: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">25</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F4: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">26</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F5: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[K~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F6: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">31</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F7: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">31</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F8: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">32</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F9: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">33</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F10: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">34</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F11: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">28</span><span class="literal">~") \n \<br>
Shift </span><span class=
"keyword"><Key></span><span class=
"literal">F12: string(</span><span class=
"number">0x1b</span><span class=
"literal">) string("[</span><span class=
"number">29</span><span class="literal">~") \n \<br>
</span><span class="keyword"><Key></span><span class="literal">Print: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">32</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Cancel: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">33</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Pause: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">34</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Insert: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">2</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Delete: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">3</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Home: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">1</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">End: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">4</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Prior: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">5</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Next: string(</span><span class="number">0x1b</span><span class="literal">) string("[</span><span class="number">6</span><span class="literal">~") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">BackSpace: string(</span><span class="number">0x7f</span><span class="literal">) \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Num_Lock: string(</span><span class="number">0x1b</span><span class="literal">) string("OP") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_Divide: string(</span><span class="number">0x1b</span><span class="literal">) string("Ol") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_Multiply: string(</span><span class="number">0x1b</span><span class="literal">) string("Om") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_Subtract: string(</span><span class="number">0x1b</span><span class="literal">) string("OS") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_Add: string(</span><span class="number">0x1b</span><span class="literal">) string("OM") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_Enter: string(</span><span class="number">0x1b</span><span class="literal">) string("OM") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_Decimal: string(</span><span class="number">0x1b</span><span class="literal">) string("On") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_0: string(</span><span class="number">0x1b</span><span class="literal">) string("Op") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_1: string(</span><span class="number">0x1b</span><span class="literal">) string("Oq") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_2: string(</span><span class="number">0x1b</span><span class="literal">) string("Or") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_3: string(</span><span class="number">0x1b</span><span class="literal">) string("Os") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_4: string(</span><span class="number">0x1b</span><span class="literal">) string("Ot") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_5: string(</span><span class="number">0x1b</span><span class="literal">) string("Ou") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_6: string(</span><span class="number">0x1b</span><span class="literal">) string("Ov") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_7: string(</span><span class="number">0x1b</span><span class="literal">) string("Ow") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_8: string(</span><span class="number">0x1b</span><span class="literal">) string("Ox") \n\<br>
</span><span class="keyword"><Key></span><span class="literal">KP_9: string(</span><span class="number">0x1b</span><span class="literal">) string("Oy") \n</span><br>
<br>
<span class=
"comment">! <Key>Up: string(0x1b) string("[A") \n\<br>
</span> <span class=
"comment">! <Key>Down: string(0x1b) string("[B") \n\<br>
</span> <span class=
"comment">! <Key>Right: string(0x1b) string("[C") \n\<br>
</span> <span class=
"comment">! <Key>Left: string(0x1b) string("[D") \n\<br>
</span> <br>
*<span class="ident2">visualBell</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
*<span class="ident2">saveLines</span>:<span class=
"literal"> </span><span class=
"number">1000</span><br>
*<span class="ident2">cursesemul</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
*<span class="ident2">scrollKey</span>:<span class=
"literal"> </span><span class="keyword">true</span><br>
*<span class="ident2">scrollBar</span>:<span class=
"literal"> </span><span class="keyword">true</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>Note that real VT220 terminals use shifted function keys to
mean something different: the user-programmable keys (i.e.,
DECUDK). Modern xterm supports this, but the translations do not
(they're using shift to select F13 to F20).</p>
<p>Here's another one, from Robert Ess
<ress@spd.dsccc.com>:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="comment">#!/bin/sh</span><br>
<br>
<span class=
"comment"># vax</span><br>
<span class=
"comment"># 09-17-96 Bob Ess - initial creation</span><br>
<span class=
"comment"># 09-26-96 Shig Katada - Additional keybindings</span><br>
<span class="comment">#</span><br>
<span class=
"comment"># Script file to incorporate keybindings and command line</span><br>
<span class=
"comment"># options for connecting to a VAX node</span><br>
<br>
<span class="comment"># Usage statement</span><br>
Usage()<span class="keyword2">{</span><br>
<span class=
"keyword">echo</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Usage : vax -options"</span><br>
<span class=
"keyword">echo</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Options: -80 for 80 column terminal"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -132 for 132 column terminal"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -fg colorname"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -bg colorname"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -fn fontname"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -fb bold fontname"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -host [altair] [devel] [leonis] [castor]"</span><br>
<span class=
"keyword">echo</span> <span class="literal">""</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Example: </span><span class=
"keyword2">\</span><span class=
"literal">"vax -80 -fg white -bg black -fn 9x15 -fb 9x15b -host castor</span><span class="keyword2">\</span><span class="literal">""</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Starts a VAX session with an 80 column terminal"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" with a black background, white foreground, a normal"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" font of 9x15 and a bold font of 9x15b, and connects"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" to the node 'castor'"</span><br>
<span class=
"keyword">echo</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" If you need additional help, please call Workstation"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Services at x92396."</span><br>
<span class=
"keyword">echo</span><br>
<span class=
"keyword">exit</span> <span class="number">1</span><br>
<span class="keyword2">}</span><br>
<br>
<span class=
"comment"># Default to a black foreground with a white background.</span><br>
<span class=
"comment"># Use the 9x15 and 9x15bold fonts. Connect to castor by default.</span><br>
<span class="comment">#</span><br>
<span class="ident2">FG</span>=black<br>
<span class="ident2">BG</span>=white<br>
<span class="ident2">HOST</span>=castor<br>
<span class="ident2">FONT</span>=<span class=
"number">9</span>x15<br>
<span class="ident2">BFONT</span>=<span class=
"number">9</span>x15bold<br>
<span class="ident2">COLS</span>=<span class=
"number">80</span><br>
<br>
<span class=
"comment"># Parse the command line arguments</span><br>
<span class="comment">#</span><br>
<span class="keyword">while</span> [ <span class=
"ident2">$#</span> != <span class=
"number">0</span> ];<br>
<span class="keyword">do</span><br>
<span class=
"keyword">case</span> <span class=
"ident2">$1</span> <span class="keyword">in</span><br>
<span class="number">-80</span>) <span class="ident2">COLS</span>=<span class="number">80</span><br>
<span class="ident2">FONT</span>=spc12x24c<br>
<span class="ident2">BFONT</span>=spc12x24b<br>
<span class="keyword">shift</span><br>
;;<br>
<span class="number">-132</span>) <span class="ident2">COLS</span>=<span class="number">132</span><br>
<span class="ident2">FONT</span>=<span class="number">9</span>x15<br>
<span class="ident2">BFONT</span>=<span class="number">9</span>x15b<br>
<span class="keyword">shift</span><br>
;;<br>
-fg) <span class="keyword">shift</span><br>
<span class="ident2">FG</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-bg) <span class="keyword">shift</span><br>
<span class="ident2">BG</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-fn) <span class="keyword">shift</span><br>
<span class="ident2">FONT</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-fb) <span class="keyword">shift</span><br>
<span class="ident2">BFONT</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-host) <span class="keyword">shift</span><br>
<span class="ident2">HOST</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-help) Usage;;<br>
*) Usage;;<br>
<span class=
"keyword">esac</span><br>
<span class="keyword">done</span><br>
<br>
xterm -title <span class=
"literal">"VAX"</span> -sb -sl <span class=
"number">1200</span> -geo <span class=
"ident2">${COLS}</span>x24 -fg <span class=
"ident2">${FG}</span> -bg <span class=
"ident2">${BG}</span> \<br>
-cr red -fn <span class="ident2">${FONT}</span> -fb <span class="ident2">${BFONT}</span> -xrm \<br>
<span class=
"literal">'XTerm*VT100.translations: #override \n\<br>
<Key>Insert: string(\001) \n\<br>
Shift <Key>Up: scroll-back(1,lines) \n\<br>
Shift <Key>Down: scroll-forw(1,lines) \n\<br>
Shift <Key>Right: string(0x1b) string("f") \n\<br>
Shift <Key>Left: string(0x1b) string("b") \n\<br>
Shift <Key>Delete: string(0x1b) string(0x08) \n\<br>
Shift <Key>Tab: string(0x1b) string("*") \n\<br>
<Key>0x1000FF0D: scroll-back(1,page) \n\<br>
<Key>0x1000FF0E: scroll-forw(1,page) \n\<br>
<Key>0x1000FF09: string(\010) \n\<br>
<Key>0x1000FF0A: string(\005) \n\<br>
<Key>BackSpace: string(0xff) \n\<br>
<Key>Select: select-start() \n\<br>
<Key>0x1000FF02: select-end(PRIMARY,CUT_BUFFER0) \n\<br>
Meta <Key>0x1000FF02: select-end(CLIPBOARD) \n\<br>
<Key>0x1000FF04: insert-selection(PRIMARY,CUT_BUFFER0) \n\<br>
Meta <Key>0x1000FF04: insert-selection(CLIPBOARD) \n\<br>
<Key>F1: string(0x1b) string("OP") \n\<br>
<Key>F2: string(0x1b) string("OQ") \n\<br>
<Key>F3: string(0x1b) string("OR") \n\<br>
<Key>F4: string(0x1b) string("OS") \n\<br>
<Key>F5: string(0x1b) string("OA") \n\<br>
<Key>F11: string(0x1b) string("[23~") \n\<br>
<Key>F12: string(0x1b) string("[24~") \n\<br>
<Key>KP_0: string(0x1b) string("Op") \n\<br>
<Key>KP_1: string(0x1b) string("Oq") \n\<br>
<Key>KP_2: string(0x1b) string("Or") \n\<br>
<Key>KP_3: string(0x1b) string("Os") \n\<br>
<Key>KP_4: string(0x1b) string("Ot") \n\<br>
<Key>KP_5: string(0x1b) string("Ou") \n\<br>
<Key>KP_Divide: string(0x1b) string("OP") \n\<br>
<Key>KP_Multiply: string(0x1b) string("[29~") \n\<br>
<Key>KP_Enter: string(0x1b) string("OM") \n\<br>
<Key>KP_Subtract: string(0x1b) string("Om") \n\<br>
<Key>KP_Add: string(0x1b) string("Ol") \n\<br>
<Key>KP_Decimal: string(0x1b) string("On") \n\<br>
<Btn1Down>: select-start() \n\<br>
<Btn1Motion>: select-extend() \n\<br>
<Btn1Up>: select-end(PRIMARY,CUT_BUFFER0) \n\<br>
Button1<Btn2Down>: select-end(CLIPBOARD) \n\<br>
Button1<Btn2Up>: ignore()'</span> \<br>
-e telnet <span class="ident2">$HOST</span> &<br>
<!--atr2html}}--></p>
</blockquote>
<p>Finally (for the moment) is a further modification of Robert
Ess's script by <a href=
"http://www-personal.une.edu.au/~oahlefel/">Erik Ahlefeldt</a>,
<oahlefel@metz.une.edu.au>. From his readme file, for
vmsterm:</p>
<blockquote>
<p>This script is for people who wish to connect from a Linux
or Unix computer to a VMS computer using telnet and get a good
VT100 or VT220 emulation. The key mappings have been
specifically designed to emulate the VT terminal auxiliary
numeric keypad, so that you can use VMS EDT and TPU editors, as
well as the many VMS applications use keys PF1 to PF4. The
script should work with any recent version of Xterm using a
standard extended IBM PC keyboard or a Sun keyboard.</p>
<p>About the keymappings. First the auxiliary numeric keypad.
My prime objective with these mappings was to produce a setup
that I could use with the EDT and TPU editors which make
extensive use of the numeric keypad. The top row of keys PC
numeric keypad (Num Lock, Divide, Multiply, Subtract) are where
you find PF1, PF2, PF3, PF4 on a VT keyboard, so I have mapped
them to PF1 thru PF4. The PC numeric keypad Add key (+) takes
up the space of two keys which are Minus and Comma on the VT
keyboard – I have mapped it to Comma (Delete Character in
the EDT editor). I have then used the PC Pause key to map to VT
key Minus (Delete Word in the EDT editor). The remaining keys
on the auxiliary numeric keypad are the same for PC and VT.</p>
<p>The six keys between the main and numeric keypads on the PC
(Insert, Home, Page Up, Delete End, Page Down) are usually
mapped to the VT keys by either position or by (approximate)
function. As I rarely use these keys I have mapped them by
function as follows: PC key Insert to VT Insert Here, PC Home
to VT Find, PC Page Up to VT Prev, PC Delete to VT Remove, PC
End to VT Select, PC Page Down to VT Next.</p>
<dl>
<dt>Function keys.</dt>
<dd>
There are 12 function keys on the PC keyboard and 20 on the
VT keyboard, so I map PC F1 thru F12 to VT F1 thru F12
(except for F1 thru F5 as noted below) and PC Shift F1 thru
Shift F10 to VT F11 thru F20.
<p>The VT keys F1 thru F5 are local hardware function keys
so there is nothing to emulate, however some PC to VT
emulations in the past have mapped PF1 thru PF4 here, so I
have done that too, even though they are already mapped on
the auxiliary numeric keypad.</p>
</dd>
<dt>Xterm functionality.</dt>
<dd>You lose some xterm functions when you remap the
keyboard, however this script implements a scroll back buffer
of 1000 lines which you scroll through using Shift and Up
(a.k.a. Up Arrow or Cursor Up key) or Shift and Down.</dd>
</dl>
</blockquote>
<p>a summary of the keyboard mapping:</p>
<blockquote>
<pre>
PC Key maps to VT Key.
------ ------
F1 PF1
F2 PF2
F3 PF3
F4 PF4
F5 unused
F6 F6
F7 F7
F8 F8
F9 F9
F10 F10
F11 F11
F12 F12
Shift F1 F11
Shift F2 F12
Shift F3 F13
Shift F4 F14
Shift F5 F15 (Help)
Shift F6 F16 (Do)
Shift F7 F17
Shift F8 F18
Shift F9 F19
Shift F10 F20
Shift F11 F11
Shift F12 F12
Print Help (F15)
Cancel Do (F16)
Pause Keypad Minus
Insert Insert Here
Delete Remove
Home Find
End Select
Prior Prev
Next Next
BackSpace BackSpace (sends DEL - ascii 127)
Num_Lock PF1
KP_Divide PF2
KP_Multiply PF3
KP_Subtract PF4
KP_Add Keypad Comma
KP_Enter Enter
KP_Decimal Period
KP_0 Keypad 0
KP_1 Keypad 1
KP_2 Keypad 2
KP_3 Keypad 3
KP_4 Keypad 4
KP_5 Keypad 5
KP_6 Keypad 6
KP_7 Keypad 7
KP_8 Keypad 8
KP_9 Keypad 9
Up Up
Shift Up Scroll Back
Down Down
Shift Down Scroll Forward
Right Right
Left Left
</pre>
</blockquote>
<p>and the script:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="comment">#!/bin/sh</span><br>
<span class=
"comment"># vmsterm</span><br>
<span class=
"comment"># from an original script by Bob Ess</span><br>
<span class=
"comment"># key translations by Erik Ahlefeldt</span><br>
<span class="comment">#</span><br>
<span class=
"comment"># Script file using Xterm and telnet to connect to a VMS host</span><br>
<span class=
"comment"># and give a decent vt220 emulation.</span><br>
<span class="comment">#</span><br>
<span class="comment"># Usage statement</span><br>
Usage()<span class="keyword2">{</span><br>
<span class=
"keyword">echo</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Usage : vmsterm -options"</span><br>
<span class=
"keyword">echo</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Options: -80 for 80 column terminal"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -132 for 132 column terminal"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -bg colorname"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -fg colorname"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -fn fontname"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -fb bold fontname"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" -host [crusher.saltmine.com] [earth] [192.168.7.7]"</span><br>
<span class=
"keyword">echo</span> <span class="literal">""</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Example: </span><span class=
"keyword2">\</span><span class=
"literal">"vmsterm -80 -fg white -bg black -fn 9x15 -fb 9x15b -host earth</span><span class="keyword2">\</span><span class="literal">""</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Starts a VMS session with an 80 column terminal"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" with a black background, white foreground, a normal"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" font of 9x15 and a bold font of 9x15b, and connects"</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" to the node 'earth'"</span><br>
<span class=
"keyword">echo</span> <span class="literal">""</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Example: </span><span class=
"keyword2">\</span><span class=
"literal">"vmsterm -host earth</span><span class=
"keyword2">\</span><span class="literal">""</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Starts a VMS session with default terminal settings "</span><br>
<span class=
"keyword">echo</span> <span class="literal">""</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Example: </span><span class=
"keyword2">\</span><span class=
"literal">"vmsterm -help</span><span class=
"keyword2">\</span><span class="literal">""</span><br>
<span class=
"keyword">echo</span> <span class=
"literal">" Displays vmsterm options "</span><br>
<span class=
"keyword">echo</span><br>
<span class=
"keyword">exit</span> <span class="number">1</span><br>
<span class="keyword2">}</span><br>
<br>
<span class=
"comment"># Default to a black foreground with a white background.</span><br>
<span class=
"comment"># Use the 9x15 and 9x15bold fonts. Connect to 192.168.3.3 by default.</span><br>
<span class="comment">#</span><br>
<span class="ident2">FG</span>=black<br>
<span class="ident2">BG</span>=white<br>
<span class="ident2">HOST</span>=192.168.3.3<br>
<span class="ident2">FONT</span>=<span class=
"number">9</span>x15<br>
<span class="ident2">BFONT</span>=<span class=
"number">9</span>x15bold<br>
<span class="ident2">COLS</span>=<span class=
"number">80</span><br>
<br>
<span class=
"comment"># Parse the command line arguments</span><br>
<span class="comment">#</span><br>
<span class="keyword">while</span> [ <span class=
"ident2">$#</span> != <span class=
"number">0</span> ];<br>
<span class="keyword">do</span><br>
<span class=
"keyword">case</span> <span class=
"ident2">$1</span> <span class="keyword">in</span><br>
<span class="number">-80</span>) <span class="ident2">COLS</span>=<span class="number">80</span><br>
<span class="ident2">FONT</span>=spc12x24c<br>
<span class="ident2">BFONT</span>=spc12x24b<br>
<span class="keyword">shift</span><br>
;;<br>
<span class="number">-132</span>) <span class="ident2">COLS</span>=<span class="number">132</span><br>
<span class="ident2">FONT</span>=<span class="number">9</span>x15<br>
<span class="ident2">BFONT</span>=<span class="number">9</span>x15b<br>
<span class="keyword">shift</span><br>
;;<br>
-fg) <span class="keyword">shift</span><br>
<span class="ident2">FG</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-bg) <span class="keyword">shift</span><br>
<span class="ident2">BG</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-fn) <span class="keyword">shift</span><br>
<span class="ident2">FONT</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-fb) <span class="keyword">shift</span><br>
<span class="ident2">BFONT</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-host) <span class="keyword">shift</span><br>
<span class="ident2">HOST</span>=<span class="ident2">$1</span><br>
<span class="keyword">shift</span>;;<br>
-help) Usage;;<br>
*) Usage;;<br>
<span class=
"keyword">esac</span><br>
<span class="keyword">done</span><br>
<br>
xterm -title <span class=
"literal">"VMSTERM"</span> -sb -sl <span class=
"number">1000</span> -geo <span class=
"ident2">${COLS}</span>x24 -fg <span class=
"ident2">${FG}</span> -bg <span class=
"ident2">${BG}</span> \<br>
-cr blue -fn <span class="ident2">${FONT}</span> -fb <span class="ident2">${BFONT}</span> -xrm \<br>
<span class=
"literal">'XTerm*VT100.translations: #override \n \<br>
~Shift <Key>F1: string(0x1b) string("OP") \n \<br>
~Shift <Key>F2: string(0x1b) string("OQ") \n \<br>
~Shift <Key>F3: string(0x1b) string("OR") \n \<br>
~Shift <Key>F4: string(0x1b) string("OS") \n \<br>
~Shift <Key>F5: string("Break") \n \<br>
~Shift <Key>F6: string(0x1b) string("[17~") \n \<br>
~Shift <Key>F7: string(0x1b) string("[18~") \n \<br>
~Shift <Key>F8: string(0x1b) string("[19~") \n \<br>
~Shift <Key>F9: string(0x1b) string("[20~") \n \<br>
~Shift <Key>F10: string(0x1b) string("[21~") \n \<br>
~Shift <Key>F11: string(0x1b) string("[23~") \n \<br>
~Shift <Key>F12: string(0x1b) string("[24~") \n \<br>
Shift <Key>F1: string(0x1b) string("[23~") \n \<br>
Shift <Key>F2: string(0x1b) string("[24~") \n \<br>
Shift <Key>F3: string(0x1b) string("[25~") \n \<br>
Shift <Key>F4: string(0x1b) string("[26~") \n \<br>
Shift <Key>F5: string(0x1b) string("[28~") \n \<br>
Shift <Key>F6: string(0x1b) string("[29~") \n \<br>
Shift <Key>F7: string(0x1b) string("[31~") \n \<br>
Shift <Key>F8: string(0x1b) string("[32~") \n \<br>
Shift <Key>F9: string(0x1b) string("[33~") \n \<br>
Shift <Key>F10: string(0x1b) string("[34~") \n \<br>
Shift <Key>F11: string(0x1b) string("[28~") \n \<br>
Shift <Key>F12: string(0x1b) string("[29~") \n \<br>
<Key>Print: string(0x1b) string("[28~") \n \<br>
<Key>Cancel: string(0x1b) string("[29~") \n \<br>
<Key>Pause: string(0x1b) string("Om") \n \<br>
<Key>Insert: string(0x1b) string("[2~") \n \<br>
<Key>Delete: string(0x1b) string("[3~") \n \<br>
<Key>Home: string(0x1b) string("[1~") \n \<br>
<Key>End: string(0x1b) string("[4~") \n \<br>
<Key>Prior: string(0x1b) string("[5~") \n \<br>
<Key>Next: string(0x1b) string("[6~") \n \<br>
<Key>BackSpace: string(0x7f) \n \<br>
<Key>Num_Lock: string(0x1b) string("OP") \n \<br>
<Key>KP_Divide: string(0x1b) string("OQ") \n \<br>
<Key>KP_Multiply: string(0x1b) string("OR") \n \<br>
<Key>KP_Subtract: string(0x1b) string("OS") \n \<br>
<Key>KP_Add: string(0x1b) string("Ol") \n \<br>
<Key>KP_Enter: string(0x1b) string("OM") \n \<br>
<Key>KP_Decimal: string(0x1b) string("On") \n \<br>
<Key>KP_0: string(0x1b) string("Op") \n \<br>
<Key>KP_1: string(0x1b) string("Oq") \n \<br>
<Key>KP_2: string(0x1b) string("Or") \n \<br>
<Key>KP_3: string(0x1b) string("Os") \n \<br>
<Key>KP_4: string(0x1b) string("Ot") \n \<br>
<Key>KP_5: string(0x1b) string("Ou") \n \<br>
<Key>KP_6: string(0x1b) string("Ov") \n \<br>
<Key>KP_7: string(0x1b) string("Ow") \n \<br>
<Key>KP_8: string(0x1b) string("Ox") \n \<br>
<Key>KP_9: string(0x1b) string("Oy") \n \<br>
~Shift <Key>Up: string(0x1b) string("[A") \n \<br>
Shift <Key>Up: scroll-back(1,lines) \n \<br>
~Shift <Key>Down: string(0x1b) string("[B") \n \<br>
Shift <Key>Down: scroll-forw(1,lines) \n \<br>
<Key>Right: string(0x1b) string("[C") \n \<br>
<Key>Left: string(0x1b) string("[D")'</span> \<br>
-e telnet <span class="ident2">$HOST</span><br>
<!--atr2html}}--></p>
</blockquote>
<h3 id="how2_title-id"><a name="how2_title" id="how2_title">How
do I set the title?</a></h3>
<p>The control sequences for doing this are documented in
<a href="xterm.faq.html#ctlseqs_ms">ctlseqs.ms</a>.</p>
<p>The usual context for this question is setting the title
according to the current working directory. People post answers
to this periodically on the newsgroups. Here is one that I have
seen, from Roy Wright <nobody@roystoy.dseg.ti.com>. In your
/etc/profile after:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">if</span> [ <span class=
"literal">"</span><span class=
"ident2">$SHELL</span><span class="literal">"</span> = <span class="literal">"/bin/pdksh"</span> -o <span class="literal">"</span><span class="ident2">$SHELL</span><span class="literal">"</span> = <span class="literal">"/bin/ksh"</span> ]; <span class="keyword">then</span><br>
<span class=
"ident2">PS1</span>=<span class=
"literal">"! $ "</span><br>
<span class="keyword">elif</span> [ <span class=
"literal">"</span><span class=
"ident2">$SHELL</span><span class="literal">"</span> = <span class="literal">"/bin/zsh"</span> ]; <span class="keyword">then</span><br>
<span class=
"ident2">PS1</span>=<span class=
"literal">"%m:%~%# "</span><br>
<span class="keyword">elif</span> [ <span class=
"literal">"</span><span class=
"ident2">$SHELL</span><span class="literal">"</span> = <span class="literal">"/bin/ash"</span> ]; <span class="keyword">then</span><br>
<span class=
"ident2">PS1</span>=<span class="literal">"$ "</span><br>
<span class="keyword">else</span><br>
<span class=
"ident2">PS1</span>=<span class=
"literal">'\u@\h:\w\$ '</span><br>
<span class="keyword">fi</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>add:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">if</span> [ <span class=
"literal">"</span><span class="ident2">$TERM</span><span class=
"literal">"</span> = <span class=
"literal">"xterm"</span> ]; <span class=
"keyword">then</span><br>
<span class=
"ident2">PS1</span>=<span class="literal">"</span><span class=
"keyword2">\</span><span class=
"literal">033]2;</span><span class=
"keyword2">\</span><span class="literal">u@</span><span class=
"keyword2">\</span><span class="literal">h:</span><span class=
"keyword2">\</span><span class="literal">w</span><span class=
"keyword2">\</span><span class=
"literal">007bash$ "</span><br>
<span class="keyword">fi</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>The terminator "\007" is a problem area.
<strong>XTerm</strong> historically uses this character, though
it is non-ANSI. The "correct" character should be a "\233" string
terminator, or "\033\\", which is the 7-bit equivalent. Modern
xterm recognizes either (the "\007" or string terminator);
waiting for the first of these.</p>
<p>You may have resource or environment problems that prevent you
from setting the title at all. Newer xterms (starting somewhere
in X11R5) use the $LANG variable. If your locale is incorrectly
installed, you will be unable to set the xterm's title. As noted
by Mikhail Teterin <mi@rtfm.ziplink.net>: Make sure that
the locale (LANG and/or LOCALE environment variable) is known to
X Window System. Check ${X11ROOT}/lib/X11/locale.* for it. If it
is not listed in either one of the files, find the nearest match
and add an alias to it. Restart X if you have made changes.</p>
<p>On a related note, some people want to know how to read the
title from an xterm. This works for modern xterm and dtterm, but
not for other variations:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="comment">#!/bin/ksh</span><br>
<span class=
"comment"># Echo the current X term title bar to standard output.</span><br>
<span class=
"comment"># Written by Icarus Sparry <icarus@bath.ac.uk> 11 Apr 1997</span><br>
<span class="comment">#</span><br>
<span class="keyword">exec</span> </dev/tty<br>
<span class="ident2">old</span>=<span class=
"keyword2">$(</span>stty -g<span class=
"keyword2">)</span><br>
stty raw -echo min <span class=
"number">0</span> <span class=
"keyword">time</span> <span class=
"ident2">${1</span><span class=
"keyword2">-</span>10<span class="ident2">}</span><br>
<span class="keyword">print</span> <span class=
"literal">"</span><span class="keyword2">\</span><span class=
"literal">033[21t</span><span class=
"keyword2">\</span><span class=
"literal">c"</span> > /dev/tty<br>
<span class="ident2">IFS</span>=<span class=
"literal">''</span> <span class=
"keyword">read</span> -r a<br>
stty <span class="ident2">$old</span><br>
<span class="ident2">b</span>=<span class=
"ident2">${a</span><span class=
"keyword2">#</span>???<span class="ident2">}</span><br>
<span class="keyword">print</span> -R <span class=
"literal">"</span><span class="ident2">${b</span><span class=
"keyword2">%</span>??<span class="ident2">}</span><span class=
"literal">"</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>But it is possible to avoid escape sequences altogether (from
Hemant Shah <shah@typhoon.xnet.com>):</p>
<blockquote>
<pre>
$ xprop -id $WINDOWID | grep WM_NAME
WM_NAME(STRING) = "this is my title"
current_title=$(xprop -id $WINDOWID | grep WM_NAME | cut -d= -f2)
</pre>
</blockquote>
<p>Here's another source of information: <a href=
"http://tldp.org/HOWTO/Xterm-Title.html">Xterm-Title
HowTo</a></p>
<h3 id="how2_blink-id"><a name="how2_blink" id="how2_blink">How
do I make the cursor blink?</a></h3>
<p>Standard xterm does not implement a blinking cursor. Some of
the variations do: dtterm, GNOME Terminal, and modern xterm (from
mid 1999, <a href="xterm.log.html#xterm_107">patch 107</a>).</p>
<h2 id="frequent_problems-id"><a name="frequent_problems" id=
"frequent_problems">Frequent problems</a></h2>
<ul>
<li>
<a href="xterm.faq.html#problems_starting">Starting xterm, or
not</a>
<ul>
<li><a href="xterm.faq.html#no_ptys">Xterm does not run (no
available pty's)</a></li>
<li><a href="xterm.faq.html#no_termcap">I need
/etc/termcap</a></li>
<li><a href="xterm.faq.html#no_libpath">Why does
$LD_LIBRARY_PATH get reset?</a></li>
<li><a href="xterm.faq.html#no_ls_and_e">Why do the -e and
-ls options not work together?</a></li>
<li><a href="xterm.faq.html#setup_resize">Why is my screen
size not set?</a></li>
<li><a href="xterm.faq.html#tiny_menus">Why are the menus
tiny?</a></li>
</ul>
</li>
<li>
<a href="xterm.faq.html#problems_fonts">Font problems</a>
<ul>
<li><a href="xterm.faq.html#no_altchar">My terminal doesn't
show box characters</a></li>
<li><a href="xterm.faq.html#scaled_font">The bold font is
ugly</a></li>
<li><a href="xterm.faq.html#little_dot">I see little dots
on the screen</a></li>
<li><a href="xterm.faq.html#no_russian">My terminal doesn't
display Cyrillic characters</a></li>
<li><a href="xterm.faq.html#utf8_fonts">I see boxes instead
of characters in uxterm</a></li>
<li><a href="xterm.faq.html#slow_menus">The first popup
menu is very slow</a></li>
</ul>
</li>
<li>
<a href="xterm.faq.html#problems_keyboard">Keyboard
problems</a>
<ul>
<li><a href="xterm.faq.html#xterm_8bits">Why can't I input
8-bit characters?</a></li>
<li><a href="xterm.faq.html#xterm_erase">Why doesn't my
delete key work?</a></li>
<li><a href="xterm.faq.html#xterm_erased">Why did my delete
key stop working?</a></li>
<li><a href="xterm.faq.html#xterm_xmodmap">Well, how can I
set my delete key?</a></li>
<li><a href="xterm.faq.html#xterm_keypad">Why doesn't my
keypad work?</a></li>
<li><a href="xterm.faq.html#xterm_pageup">Why can't I use
the pageup/pagedown keys?</a></li>
<li><a href="xterm.faq.html#xterm_pc_style">Why can't I use
the home/end keys?</a></li>
<li><a href="xterm.faq.html#xterm_arrows">Why can't I use
the cursor keys in (whatever) shell?</a></li>
<li><a href="xterm.faq.html#bash_meta_mode">Alt-keys do not
work in bash</a></li>
</ul>
</li>
<li>
<a href="xterm.faq.html#problems_colors">Colors and other
graphic rendition</a>
<ul>
<li><a href="xterm.faq.html#no_color">My terminal doesn't
recognize color</a></li>
<li><a href="xterm.faq.html#xterm_terminfo">What $TERM
should I use?</a></li>
<li><a href="xterm.faq.html#xterm_hilite">Reverse video is
not reset</a></li>
<li><a href="xterm.faq.html#vim_16colors">My colors changed
in vim</a></li>
<li><a href="xterm.faq.html#bold_vs_16colors">Aren't bright
colors the same as bold?</a></li>
<li><a href="xterm.faq.html#dont_like_blue">I don't like
that shade of blue</a></li>
<li><a href="xterm.faq.html#why_no_italics">Why doesn't
xterm support italics?</a></li>
<li><a href="xterm.faq.html#grep_colors">"grep --color"
does not show the right output</a></li>
<li><a href="xterm.faq.html#vt100_wrapping">That
description of wrapping is odd, say more?</a></li>
</ul>
</li>
<li>
<a href="xterm.faq.html#problems_weird">Odd behavior</a>
<ul>
<li><a href="xterm.faq.html#xterm_paste">Why can't I
cut/paste in xterm?</a></li>
<li><a href="xterm.faq.html#xterm_tabs">Why can't I select
tab-characters in xterm?</a></li>
<li><a href="xterm.faq.html#xterm_resize">FVWM does weird
things when I try to resize xterm</a></li>
<li><a href="xterm.faq.html#xterm_tite">Why doesn't the
screen clear when running vi?</a></li>
<li><a href="xterm.faq.html#xterm_vite">Why is the cursor
misplaced after running vi?</a></li>
<li><a href="xterm.faq.html#narrowproto">Why doesn't the
scrollbar work?</a></li>
<li><a href="xterm.faq.html#window_ops">Why can't my
program read the window title?</a></li>
<li><a href="xterm.faq.html#window_ops2">Why can't my
program set the window size?</a></li>
<li><a href="xterm.faq.html#compiz_bugs">Why is the text in
the wrong place?</a></li>
</ul>
</li>
<li><a href="xterm.faq.html#warning_msg">What is this warning
message?</a></li>
</ul>
<h3 id="problems_starting-id"><a name="problems_starting" id=
"problems_starting">Starting xterm, or not</a></h3>
<h4 id="no_ptys-id"><a name="no_ptys" id=
"no_ptys"><strong>XTerm</strong> does not run (no available
pty's)</a></h4>
<p>Your copy of xterm may not have enough permissions to use
existing pty's:</p>
<ul>
<li>you may have to make xterm run setuid to root (though newer
systems have wrappers that make this unnecessary).</li>
<li>the pty's permissions may be restrictive (that is ok, but
you have to make xterm agree with it). Usually this is done by
making the group ownership of the pty's "tty", and requiring
that xterm run setgid to "tty". This is done rather than make
xterm run setuid to root, since that presents problems with
security.</li>
<li>newer systems (with Unix98 pty's) have a single entry under
/dev which has to have the right permissions. For example:
<blockquote>
<pre>
# ls -l /dev/ptmx
crw-rw---- 1 root tty 5, 2 Aug 21 20:19 /dev/ptmx
</pre>
</blockquote>
</li>
</ul>
<p>Perhaps your system does not have enough pty's, or (problems
reported with newer Linux kernels supporting Unix98 pty's,
beginning with RedHat 6.0) the major device numbers of the pty's
may have changed during a kernel upgrade. (This is described in
<code>/usr/src/linux/Documentation</code>).</p>
<p>See also the MAKEDEV script, which usually exists under
/dev.</p>
<h4 id="no_termcap-id"><a name="no_termcap" id="no_termcap">I
need /etc/termcap</a></h4>
<p>If you have a termcap version of xterm on a system with no
termcap libraries, you may also be missing /etc/termcap.</p>
<p>A workaround is to copy /usr/X11R6/lib/X11/etc/xterm.termcap
to /etc/termcap.</p>
<p>This is fixed another way starting with XFree86 3.3.1. If
xterm cannot find the terminal description, it will accept that,
though it will print a warning. If xterm does not find the
termcap entry, it will not set the $TERMCAP variable.</p>
<h4 id="no_libpath-id"><a name="no_libpath" id="no_libpath">Why
does $LD_LIBRARY_PATH get reset?</a></h4>
<p>If xterm is running setuid (which is needed on some systems
which have no wrappers for opening pty's and updating utmp),
newer systems automatically set or reset environment variables
which are considered security problems. These include
<code>$PATH</code> and <code>$LD_LIBRARY_PATH</code>, since they
affect the choice of which programs are run if not specified via
a full pathname.</p>
<p>This means, for example, that if you attempt to run</p>
<blockquote>
<pre>
xterm -e foo
</pre>
</blockquote>
<p>where <code>foo</code> is a program that uses shared libraries
in <code>/usr/local/lib</code>, then the command will fail,
because <code>/usr/local/lib</code> is not considered part of
<code>root</code>'s environment.</p>
<p>Modern Unix systems (such as recent Solaris and HPUX versions)
do not require you to run xterm setuid. Some will result in odd
malfunctions if you do this.</p>
<h4 id="no_ls_and_e-id"><a name="no_ls_and_e" id=
"no_ls_and_e">Why do the -e and -ls options not work
together?</a></h4>
<p><strong>XTerm</strong> has two useful options for controlling
the shell that is run:</p>
<dl>
<dt>-e</dt>
<dd>tells xterm to execute a command using the remaining
parameters after this option.</dd>
<dt>-ls</dt>
<dd>tells xterm to invoke a login shell, making it read your
<code>.login</code> file, for instance.</dd>
</dl>
<p>The two are not compatible. If you specify both, xterm uses
<code>-e</code>, and if that fails for whatever reason will fall
through to the <code>-ls</code> option. It cannot (in general)
combine the two, since some shells permit this (e.g., bash), and
others do not (e.g., tcsh).</p>
<h4 id="setup_resize-id"><a name="setup_resize" id=
"setup_resize">Why is my screen size not set?</a></h4>
<p>Well, it may be set, but not correctly. You may notice these
symptoms:</p>
<ul>
<li>When editing with vi, you cannot see the beginning of the
file, or</li>
<li>Running
<blockquote>
<pre>
stty -a
</pre>
</blockquote>
<p>shows the rows and/or columns values as 0, or some other
value (such as 65) which has nothing to do with the actual
window size.</p>
</li>
</ul>
<p><strong>XTerm</strong> knows how big the screen is (of
course), and tries to tell your applications (e.g., by invoking
ioctl's and sending SIGWINCH). But sometimes it cannot:</p>
<ul>
<li><strong>XTerm</strong> itself may have been built
incorrectly (the #ifdef's that make the logic work are
inactive).</li>
<li>You may be running xterm via a remote connection which
refuses to pass that information. This can happen even on
"modern" networks where the connection crosses domain
boundaries.</li>
<li>You may be running su'd to another account. SIGWINCH is
just another signal; signals do not propagate for security
reasons.</li>
</ul>
<p>Most full-screen applications such as vi are designed to use
the ioctl calls that return the screen size. When they fail, the
applications use the size defined in the terminal's terminfo or
termcap description.</p>
<p>You may be able to use the <em>resize</em> program to issue
the ioctl's that will notify your application of the actual
screen size. This does not always work for the reasons just
mentioned. Newer versions of stty let you specify the screen
size, though it will not be updated if you resize the xterm
window:</p>
<blockquote>
<pre>
<code>stty rows 24 columns 80
</code>
</pre>
</blockquote>
<p>Most full-screen applications also check if the $LINES and
$COLUMNS variables are set, using those values to override the
terminal description:</p>
<blockquote>
<pre>
<code>setenv LINES 24
setenv COLUMNS 80</code>
</pre>
</blockquote>
<p>Why 65 lines? The standard xterm terminfo description
specifies 65 lines, perhaps because someone liked it that way.
Real VT100's are 24 lines. I once used (and wrote applications
for) a Bitgraph terminal, which emulated VT100, but displayed 65
lines.</p>
<h4 id="tiny_menus-id"><a name="tiny_menus" id="tiny_menus">Why
are the menus tiny?</a></h4>
<p>Everything seems to work, except that the xterm menus (VT
options, fonts, etc.) do not display properly; the menus pop up,
but only with a tiny display area in which none of the options
are visible (and only part of the menu title is visible).</p>
<p>You have specified the geometry for xterm too high in the
hierarchy, and that 24x80 (or whatever the -geometry parameter
happens to be) is applying to the menus in pixels. This resource
makes the geometry apply to the menus as well as the VT100
widget:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"ident2">geometry</span>:<span class=
"literal"> 80x24</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>while this applies only to the VT100 widget (which is probably
what you intended):</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>.<span class=
"keyword">VT100</span>.<span class=
"ident2">geometry</span>:<span class=
"literal"> 80x24</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>or better yet (to allow for the toolbar option, which uses a
level of widget hierarchy):</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">geometry</span>:<span class=
"literal"> 80x24</span><br>
<!--atr2html}}--></p>
</blockquote>
<h3 id="problems_fonts-id"><a name="problems_fonts" id=
"problems_fonts">Font problems</a></h3>
<h4 id="no_altchar-id"><a name="no_altchar" id="no_altchar">My
terminal doesn't show box characters</a></h4>
<p><strong>XTerm</strong> displays the 7-bit ASCII and VT100
graphic characters (including box corners) using specially
arranged fixed-pitch fonts. The first 32 glyph positions (which
would correspond to nonprinting control characters) are used to
hold the VT100 graphic characters. Some fonts that otherwise look
fine (such as courier) do not have glyphs defined for these
positions. So they display as blanks. Use <em>xfd</em> to display
the font.</p>
<p>Modern xterm can form its own line-drawing characters (see
<a href="xterm.log.html#xterm_90">patch 90</a>, for example). It
does not draw all of the graphic characters, only those that may
be done with straight lines. But those are the most used, making
most of the fixed-pitch fonts useful for xterm.</p>
<p>You may also have a problem with the terminfo description. As
distributed, the X11R6 terminfo for xterm does not have the
<em>acsc</em> string defined, so most implementations of curses
do not try to use the alternate character set.</p>
<p>Finally, some people confuse the VT100 graphic characters with
the VT220 support for DEC technical character set. These are
distinct (7-bit) character sets. Xterm currently does not support
this.</p>
<h4 id="scaled_font-id"><a name="scaled_font" id=
"scaled_font">The bold font is ugly</a></h4>
<p><strong>XTerm</strong> lets you directly specify one bold
font, which is assumed to correspond to the default font. Older
versions of xterm make a fake bold font for the other choices via
the fonts menu by drawing the characters offset by one pixel. I
modified xterm to ask the font server for a bold font that
corresponds to each font (other than the default one). Usually
that works well. However, sometimes the font server gives a poor
match. Xterm checks for differences in the alignment and size,
but the font server may give incorrect information about the font
size. The scaled bitmap font feature gives poor results for the
smaller fonts. In your X server configuration file, that can be
fixed by disabling the feature, e.g., by appending ":unscaled" to
the path:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
FontPath "<span class="literal">/usr/lib/X11/fonts/100dpi/:unscaled</span>"<br>
FontPath "<span class="literal">/usr/lib/X11/fonts/75dpi/:unscaled</span>"<br>
FontPath "<span class="literal">/usr/lib/X11/fonts/misc/:unscaled</span>"<br>
<!--atr2html}}--></p>
</blockquote>
<p>You can suppress xterm's overstriking for bold fonts using the
<code>alwaysBoldMode</code> and related resources. However,
rendering ugly bold fonts is a "feature" of the font server. In
particular, the TrueType interface provides less ability to the
client for determining if a particular font supports a bold
form.</p>
<h4 id="little_dot-id"><a name="little_dot" id="little_dot">I see
little dots on the screen</a></h4>
<p>Well, I do. Perhaps you do not. It depends on the fonts you
choose, and how you use them.</p>
<p>Standard xterm has a "normal" font for which a bold font can
be chosen, and several alternative fonts, useful for changing the
font size. The alternative fonts do not have corresponding bold
fonts. Xterm simulates bold fonts in this case by overstriking
the character one pixel offset. That can make an bold character
extend into the area that another character occupies. When
erasing a bold character from the screen, xterm does not erase
the extra pixel. This is corrected in modern xterm, subject to
the available fonts (from late 1998, <a href=
"xterm.log.html#xterm_85">patch 85</a>). For each font, it asks
the font server for a corresponding bold font. Your font server
may not have the bold font (or it may incorrectly report that it
does). But it usually works.</p>
<h4 id="no_russian-id"><a name="no_russian" id="no_russian">My
terminal doesn't display Cyrillic characters</a></h4>
<p>Cyrillic encodings typically use characters in the range
128-159. For a VT220 (or any terminal that follows ISO 6429),
those are treated as control characters. Still, some people want
to use KOI8-R, etc. I modified xterm in <a href=
"xterm.log.html#xterm_175">patch 175</a> to add an option
(<code>-k8</code>) and corresponding resource settings to allow
them to customize their environment. Here is a <a href=
"ftp://invisible-island.net/xterm/koi8-term">sample script</a>
and <a href="ftp://invisible-island.net/xterm/KOI8Term">resource
file</a> which I use for testing this configuration.</p>
<h4 id="utf8_fonts-id"><a name="utf8_fonts" id="utf8_fonts">I see
boxes instead of characters in uxterm</a></h4>
<p><strong>XTerm</strong> may show boxes instead of characters if
the font that you have selected does not contain those
characters. Normally you can fix most of that using the UTF-8
feature, with <code>uxterm</code>. However, your X resource
settings may be the source of the problem.</p>
<p>One pitfall to setting X resources is that they allow you to
specify wildcards, e.g., the "*" character. When you give a
wildcard, the X resource matches any number of levels in the
widget hierarchy.</p>
<p><strong>XTerm</strong> has more than one widget matching
"font" at different levels of the hierarchy. There are the popup
menus, and there are the fonts used for <code>uxterm</code>. The
latter is where an overbroad pattern can cause xterm to use a
different font than you expect.</p>
<p>Suppose your resource setting includes this pattern</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class="keyword">VT100</span>*<span class=
"ident2">font</span>:<span class=
"literal"> fixed</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>It could be interpreted as this:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class="keyword">VT100</span>.<span class=
"ident2">font</span>:<span class=
"literal"> fixed</span><br>
*<span class="keyword">VT100</span>.<span class=
"ident2">utf8Fonts</span>.<span class=
"ident2">font</span>:<span class=
"literal"> fixed</span><br>
<!--atr2html}}--></p>
</blockquote>
<p><strong>XTerm</strong> uses the <code>utf8Fonts</code>
subresources to provide runtime-switchable fonts between
IS0-8859-1 (Latin-1) and ISO-10646 (Unicode). Modifying the
Unicode font to "fixed" will make most of the characters
unavailable (i.e., shown as boxes). If instead your resource
looks like</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class="keyword">VT100</span>.<span class=
"ident2">font</span>:<span class=
"literal"> fixed</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>it would be unambiguous, and not modify the
<code>utf8Fonts</code> value.</p>
<h4 id="slow_menus-id"><a name="slow_menus" id="slow_menus">The
first popup menu is very slow</a></h4>
<p>Some users report that when starting xterm, it is very slow,
that their computer's CPU time increases, etc.</p>
<p>This is a longstanding bug in the X libraries. There is a
workaround using a resource setting for xterm.</p>
<h5 id="slow_menus_details-id">Details</h5>
<p><strong>XTerm</strong> uses the Athena (Xaw) widgets to
display popup menus. In the normal case, those are initialized
one-by-one as they are first used. If you have configured xterm
to use its toolbar configuration, they are all initialized on
startup. In the latter, performance problems are more
noticeable.</p>
<p>The Athena widgets <code>XawInitializeWidgetSet</code>
function goes through several levels down to the X library
<code>_XlcAddUtf8LocaleConverters</code> function to call
<code>create_tocs_conv</code> and related functions to make a
list of character sets from the locale, which is used in menus to
get all possible fonts needed for a fontset.</p>
<p>If your current locale uses <em>UTF-8</em> encoding, this will
read a long list of bitmap fonts—everything whose
<em>encoding</em> might be useful for displaying the menus. For
example, this list (from <code>lcUTF8.c</code>) which dates from
around 2000 is the core of the problem:</p>
<blockquote>
<p>ISO10646-1, ISO8859-1, ISO8859-2, ISO8859-3, ISO8859-4,
ISO8859-5, ISO8859-6, ISO8859-7, ISO8859-8, ISO8859-9,
ISO8859-10, ISO8859-11, ISO8859-13, ISO8859-14, ISO8859-15,
ISO8859-16, JISX0201.1976-0, TIS620-0, GB2312.1980-0,
JISX0208.1983-0, JISX0208.1990-0, JISX0212.1990-0,
KSC5601.1987-0, KOI8-R, KOI8-U, KOI8-C, TATAR-CYR, ARMSCII-8,
IBM-CP1133, MULELAO-1, VISCII1.1-1, TCVN-5712,
GEORGIAN-ACADEMY, GEORGIAN-PS, ISO8859-9E, MICROSOFT-CP1251,
MICROSOFT-CP1255, MICROSOFT-CP1256, BIG5-0, BIG5-E0, BIG5-E1,
ISO10646-1, ISO10646-1</p>
</blockquote>
<p>However, xterm is going to use only the characters shown in
the popup menus. It is unlikely that you need Chinese fonts for
that.</p>
<h5 id="slow_menus_solution-id">Solution</h5>
<p><strong>XTerm</strong>'s <code>menuLocale</code> resource can
be set to an explicit value, e.g., "C" to override the current
locale as seen by this initialization debacle.</p>
<h5 id="slow_menus_limits-id">Limitations</h5>
<p>The workaround does not prevent some hacker from "improving"
the X libraries still further.</p>
<h3 id="problems_keyboard-id"><a name="problems_keyboard" id=
"problems_keyboard">Keyboard problems</a></h3>
<h4 id="xterm_8bits-id"><a name="xterm_8bits" id=
"xterm_8bits">Why can't I input 8-bit characters?</a></h4>
<p>You must have the <code>eightBitInput</code> resource set to
do this.</p>
<h4 id="xterm_erase-id"><a name="xterm_erase" id=
"xterm_erase">Why doesn't my delete key work?</a></h4>
<p>This seems to be a problem with the older XFree86 release
(3.1.2). I have picked up pieces of the story (xterm and the
keyboard work as designed under XFree86 3.2 and up).</p>
<p>The underlying problem is that we've accumulated three things
that are being equated as "Delete":</p>
<blockquote>
<pre>
ASCII backspace (code 8)
ASCII delete (code 127)
VT220 "remove" aka "delete" (ESC [ 3 ~)
</pre>
</blockquote>
<p>You are probably talking about the <strong>backarrow</strong>
key (on my keyboard, at the upper right of the QWERTY block), or
the key labeled <strong>delete</strong> which is on the 6-key
"editing keypad". Since xterm is emulating a VT100/VT220, the
backarrow key should generate a 127 (often displayed as
<code>^?</code>). You would use a control/H to obtain a backspace
on a real VT220.</p>
<p>Tastes differ on Unix, people expect the backarrow key to
generate a backspace (or not). As I understand it, at one point,
XFree86 picked up the sense of the erase character during
initialization, so that xterm would in effect use the same erase
character as the console. The current scheme (X11R6) uses
keyboard mapping tables that are independent of the
environment.</p>
<p>Modern xterm provides a resource toggle <em>backarrowKey</em>
(and an escape sequence from VT320) that changes this key between
the two styles (backspace or delete).</p>
<p>With modern xterm <a href="xterm.log.html#xterm_95">patch
95</a> (also in the stable version as "88c"), you may have an
xterm which can automatically initialize the backarrow key to
backspace or delete depending on the pseudo terminal's sense, or
based on the termcap setting of <em>kbs</em> (backspace key).
This feature is controlled by the resource setting
<em>ptyInitialErase</em>.</p>
<h4 id="xterm_erased-id"><a name="xterm_erased" id=
"xterm_erased">Why did my delete key stop working?</a></h4>
<p>Well, something changed. You have to determine what did.</p>
<p>This may be because an upgrade introduced different X resource
settings, or because you are using the newer xterm with the
<em>ptyInitialErase</em> resource (or perhaps both). Use</p>
<blockquote>
<pre>
appres XTerm
</pre>
</blockquote>
<p>to see the X resources that you are using, in particular the
<code>translation</code> (or <code>Translation</code>) resource
for the vt100 widget.</p>
<p>One unexpected scenario came out of hiding when I was
implementing the <em>ptyInitialErase</em> resource. When xterm is
(by default) built to support this, it sets the pty's erase
character to match the termcap entry. Xterm also sets the
$TERMCAP environment variable to match. So everything is
consistent, and everything defined. The <code>stty erase</code>
character is either backspace (^H) or delete (^?).</p>
<p>The problem arises because there are two things called
"delete", which were not well-defined: ASCII delete (127) and the
PC-style adaptation of VT220 <kbd>remove</kbd> assigned to the
key Delete.</p>
<p>However, the <em>screen</em> program prefers to make the
termcap delete (<code>kD</code>) an <escape>[3~, which
corresponds to the VT220 <kbd>remove</kbd> key. If $TERMCAP is
set when starting <em>screen</em>, it will translate stty's erase
character into the <escape>[3~, making most curses and
termcap applications work. But stty still has the original erase
character. So low-level applications which check stty will not
work. I found that unsetting $TERMCAP before running would work,
but this was not a good solution. Someone pointed out (see
<a href="xterm.log.html#xterm_129">patch 129</a>), that the
problem really was because termcap <code>kD</code> should delete
the character at the current position. So it cannot be the same
as <code>stty erase</code>.</p>
<p>As a matter of fact, <code>stty erase</code> has to be a
single character, so <escape>[3~ would not work anyway.</p>
<h4 id="xterm_xmodmap-id"><a name="xterm_xmodmap" id=
"xterm_xmodmap">Well, how can I set my delete key?</a></h4>
<p>When people first started asking this question in 1995-1996,
it appeared in the context of making Netscape work. Netscape's
use of the delete key running in X did not match user's
expectations when compared to that other platform. They were
commonly advised to use <em>xmodmap</em>, e.g.,</p>
<blockquote>
<pre>
keysym BackSpace = Delete
</pre>
</blockquote>
<p>or</p>
<blockquote>
<pre>
keycode 22 = 0xff08
</pre>
</blockquote>
<p>Either way is a bad technical solution – it works for
some people but not others (on my keyboard at work, keycode 22 is
the numeric keypad '9').</p>
<p>Alternatively, you can set resources. This works reasonably
well for environments where you have different versions of xterm,
e.g.,</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">translations</span>:<span class=
"literal"> #override \n\<br>
<Key>Delete: string(</span><span class="number">0x7f</span><span class="literal">)</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>I do not do that either, because it is not flexible. Not all
programs use the same sense of <code>stty erase</code>; some use
termcap or terminfo, and some are hardcoded. So I prefer to be
able to switch the xterm's keyboard at runtime. You cannot do
that with resources. (Or not really – xterm has a
<code>keymap()</code> action which could support this if you
provided a rather complex resource settings, but the X library
support for that is broken in X11R6). Instead, I have added to
xterm a set of resources (and popup menu entries) to allow simple
switching between the different styles of keyboard, in particular
for the backspace/delete issues. See the manual page for
<code>backarrowKey</code> <code>backarrowKeyIsErase</code> and
<code>deleteIsDEL</code> as well as <code>sunKeyboard</code>.</p>
<h4 id="xterm_keypad-id"><a name="xterm_keypad" id=
"xterm_keypad">Why doesn't my keypad work?</a></h4>
<p>A few people have commented that the keypad does not work
properly. Aside from bugs (I have fixed a few), the most common
problem seems to be misconception.</p>
<p>Here's a picture of the VT100 numeric keypad:</p>
<blockquote>
<pre>
+-----+-----+-----+-----+
| PF1 | PF2 | PF3 | PF4 |
+-----+-----+-----+-----+
| 7 | 8 | 9 | - |
+-----+-----+-----+-----+
| 4 | 5 | 6 | , |
+-----+-----+-----+-----+
| 1 | 2 | 3 | |
+-----+-----+-----+ ENT +
| 0 | . | |
+-----+-----+-----+-----+
</pre>
</blockquote>
<p>and the similar Sun and PC keypads:</p>
<blockquote>
<pre>
+-----+-----+-----+-----+
| NUM | / | * | - |
+-----+-----+-----+-----+
| 7 | 8 | 9 | |
+-----+-----+-----+ + +
| 4 | 5 | 6 | |
+-----+-----+-----+-----+
| 1 | 2 | 3 | |
+-----+-----+-----+ ENT +
| 0 | . | |
+-----+-----+-----+-----+
</pre>
</blockquote>
<p>Working in X11, the NUM (NumLock) key has better uses than an
alias for PF1 (and is sometimes reserved). I use the F1 through
F4 on the keyboard to implement PF1 through PF4, alias the keypad
"+" to "," and use the existing "-" key.</p>
<p>VT220 emulation uses the VT100 numeric keypad as well as a
6-key editing keypad. Here's a picture of the VT220 editing
keypad:</p>
<blockquote>
<pre>
+--------+--------+--------+
| Find | Insert | Remove |
+--------+--------+--------+
| Select | Prev | Next |
+--------+--------+--------+
</pre>
</blockquote>
<p>and the similar Sun and PC keypads:</p>
<blockquote>
<pre>
+--------+--------+--------+
| Insert | Home | PageUp |
+--------+--------+--------+
| Delete | End | PageDn |
+--------+--------+--------+
</pre>
</blockquote>
<p>I chose to use keys that are mnemonic rather than in the
"same" positions, though some emulators (e.g., Tera Term) use the
same positions:</p>
<blockquote>
<pre>
+--------+--------+--------+
| Insert | Find | Prev |
+--------+--------+--------+
| Remove | Select | Next |
+--------+--------+--------+
</pre>
</blockquote>
<p>I test the keyboard (for VT52/VT100/VT220) using <a href=
"../vttest/vttest.html">vttest</a>. If you find (or think that
you have found) a problem with the keyboard handling of xterm,
please test it with vttest first.</p>
<p>Other arrangements of the keyboard are possible of course. If
you prefer to use the top row of the numeric keypad as PF1
through PF4, you should do this using xterm's X resources.</p>
<h4 id="xterm_pageup-id"><a name="xterm_pageup" id=
"xterm_pageup">Why can't I use the pageup/pagedown keys?</a></h4>
<p>Some vendors, e.g,. Sun, have added key translations which
make the pageup and pagedown keys talk to the xterm's scrollbar
instead of your application. They did the same thing for the home
and end keys, thereby obscuring a bug in <a href=
"xterm.faq.html#bug_xterm_r6">xterm</a>.</p>
<p>You can override this by specifying your own translations in
your resource file. Use the translations in</p>
<blockquote>
<pre>
/usr/lib/X11/app-defaults/XTerm
</pre>
</blockquote>
<p>as a guide. The relevant section of the app-default file looks
like</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class="keyword">VT100</span>.<span class=
"ident2">translations</span>:<span class=
"literal"> #override \<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_0: string(</span><span class="number">0</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_1: string(</span><span class="number">1</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_2: string(</span><span class="number">2</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_3: string(</span><span class="number">3</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_4: string(</span><span class="number">4</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_5: string(</span><span class="number">5</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_6: string(</span><span class="number">6</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_7: string(</span><span class="number">7</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_8: string(</span><span class="number">8</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_9: string(</span><span class="number">9</span><span class="literal">)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_Add: string(+)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_Decimal: string(.)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_Divide: string(/)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_Enter: string(\015)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_Equal: string(=)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_Multiply: string(*)\n\<br>
@Num_Lock</span><span class="keyword"><Key></span><span class="literal">KP_Subtract: string(-)\n\<br>
</span><span class="keyword"><Key></span><span class="literal">Prior:scroll-back(</span><span class="number">1</span><span class="literal">,page)\n\<br>
</span><span class="keyword"><Key></span><span class="literal">Next:scroll-forw(</span><span class="number">1</span><span class="literal">,page)\n\<br>
</span><span class="keyword"><Key></span><span class="literal">F16: start-extend() select-end(PRIMARY, CUT_BUFFER0, CLIPBOARD) \n\<br>
</span><span class="keyword"><Key></span><span class="literal">F18: insert-selection(PRIMARY, CLIPBOARD) \n\<br>
</span><span class="keyword"><Key></span><span class="literal">F27: scroll-back(</span><span class="number">100</span><span class="literal">,page) \n\<br>
</span><span class="keyword"><Key></span><span class="literal">R13: scroll-forw(</span><span class="number">100</span><span class="literal">,page) \n\<br>
</span><span class="keyword"><Key></span><span class="literal">Home: scroll-back(</span><span class="number">100</span><span class="literal">,page) \n\<br>
</span><span class="keyword"><Key></span><span class="literal">End: scroll-forw(</span><span class="number">100</span><span class="literal">,page) \n</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>For example, a more-specific pattern for the resource name
lets you override:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">translations</span>:<span class=
"literal"> #override \n\<br>
~Shift</span><span class="keyword"><Key></span><span class="literal">Home: string(\033[</span><span class="number">1</span><span class="literal">~)\n\<br>
~Shift</span><span class="keyword"><Key></span><span class="literal">End: string(\033[</span><span class="number">4</span><span class="literal">~)\n\<br>
~Shift</span><span class="keyword"><Key></span><span class="literal">Prior: string(\033[</span><span class="number">5</span><span class="literal">~)\n\<br>
~Shift</span><span class="keyword"><Key></span><span class="literal">Next: string(\033[</span><span class="number">6</span><span class="literal">~)\n\<br>
Shift</span><span class="keyword"><Key></span><span class="literal">Prior: scroll-back(</span><span class="number">1</span><span class="literal">,page) \n\<br>
Shift</span><span class="keyword"><Key></span><span class="literal">Next: scroll-forw(</span><span class="number">1</span><span class="literal">,page) \n\<br>
Shift</span><span class="keyword"><Key></span><span class="literal">Home: scroll-back(</span><span class="number">100</span><span class="literal">,page) \n\<br>
Shift</span><span class="keyword"><Key></span><span class="literal">End: scroll-forw(</span><span class="number">100</span><span class="literal">,page) \n</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>makes the home/end and pageup/pagedown keys usable by your
editor, while leaving their shifted equivalents available for the
scrollbar.</p>
<h4 id="xterm_pc_style-id"><a name="xterm_pc_style" id=
"xterm_pc_style">Why can't I use the home/end keys?</a></h4>
<p>This is a long story, unless you are referring to X Consortium
<a href="xterm.faq.html#bug_xterm_r6">xterm</a>. That program is
simply broken in this respect.</p>
<p>At the beginning, when the home/end keys were fixed for modern
xterm (in early 1996), there was some discussion regarding what
the escape sequences should be for those keys (for the 6-key
editing keypad). Those were chosen as "PC-style" codes (like SCO
"ansi"), i.e.,</p>
<blockquote>
<pre>
ESC [ H
ESC [ F
</pre>
</blockquote>
<p>for normal mode, and</p>
<blockquote>
<pre>
ESC O H
ESC O F
</pre>
</blockquote>
<p>for cursor application mode.</p>
<p>That style of coding fit easily into the existing logic of
xterm. It was not my change, and (because xterm should be based
upon standards), I did question this, and asked the opinion of
the person who was at that time developing rxvt. He had chosen a
layout based on DEC's VT220 terminals, though the key labels on
the typical PC keyboard did not <a href=
"xterm.faq.html#xterm_keypad">match</a>. At that point, neither
of us knew enough to make a good case for this.</p>
<p>Somewhat later I could see that xterm had a number of
undocumented extensions to support the VT220-style (pre-ISO 2022)
character sets. I decided to complete the functionality by making
xterm a VT220 emulator. This would require that it provide the
same escape sequences for the editing and numeric keypads. I
could not simply change the escape sequences from "PC-style" to
"VT220-style", since a number of users "knew" that the keypad
"ought to" send home, end, cursor keys, etc., because they had
labels indicating that use. To retain compatibility (but allow
easy reconfiguration to make a VT220 emulator), I added
popup-menu items to switch between the modes. With minor
refinements, this was the approach for about two years,
culminating with the <a href="xterm.log.html#xterm_88">"stable"
patch #88</a>, which is essentially the version distributed with
XFree86 3.3.x.</p>
<dl>
<dt><em>NOTE</em>:</dt>
<dd>
the terminfo distributed with xterm patch #88 is incorrect:
the escape sequences given for home/end keys are the
VT220-style, rather than the default PC-style. Too accustomed
to switching modes on the fly, I overlooked a line in my
.Xdefaults file:
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class="ident2">sunKeyboard</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>Downstream packagers (when they noticed this) accommodated
the bug by modifying the VT100 translations resource which is
not a good technical solution since it interferes with the
users' ability to modify that resource. See <a href=
"xterm.faq.html#xterm_xmodmap">this</a> for more
discussion.</p>
</dd>
</dl>
<p>But xterm continues to evolve past the stable patch #88. The
keyboard support was still unsatisfactory for two reasons:</p>
<ul>
<li>some users wanted to be able to use applications that
detected whether the control key was pressed (e.g.,
control/F1).</li>
<li>the compromises made for <code>xkb</code> with X11R6
interfered with xterm's use of the NumLock key for the numeric
keypad.</li>
</ul>
<p>The former could be addressed by expanding the escape
sequences sent by the PC-style function keys, while the latter
was a VT100/VT220 design issue. I decided to redesign
function-key support to separate the two styles of function keys
better, but leaving the choice still controlled by the
<code>sunKeyboard</code> resource. Partway through that, I was
asked to do similar cleanup and redesign of the backspace and
delete key handling, e.g., the <a href=
"xterm.faq.html#xterm_erased">ptyInitialErase</a> resource.
Because it is a redesign, I chose to not make the keyboard
differences between the old and new xterms completely compatible.
If you were to run both on the same system, one or the other
would have some problems with the editing keypad or the
backspace/delete keys which would be addressed by the popup-menu
selections.</p>
<p>For example, at this time (2001/9/4):</p>
<ul>
<li>Debian stable is xterm-88c, which should be identical to
the XFree86 3.3.6 version, but is not (there are some label
differences in the resource-file, but nothing interesting
relative to home/end keys). And of course, Debian changes the
terminfo <code>kbs</code> from <code>^H</code> to
<code>^?</code>. As noted, the terminfo I wrote for XFree86
3.3.x has an error. Setting
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class="ident2">sunKeyboard</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>in the app-defaults file fixes the problem with xterm-88,
which was that I documented in the terminfo the behavior
<em>with</em> that resource set. Similarly, setting</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class="ident2">backarrowKey</span>:<span class=
"literal"> </span><span class=
"keyword">false</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>is one way to address Debian's change to
<code>kbs</code>.</p>
</li>
<li>Debian unstable is xterm-149. Other than omitting the color
resources from the app-defaults file, I see that it sets
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class=
"ident2">backarrowKeyIsErase</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>which would not affect the home/end keys. (The color
resources are redundant, so that is not a problem
either).</p>
</li>
</ul>
<p><a href="XTerm-debian-88c">Here is a resource file</a> which I
tested with xterm-88c, xterm-149 and xterm-158, using $TERM set
to xterm-debian:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="comment">! $Id: xterm.faq.html,v 1.169
2012/02/05 11:58:56 tom Exp $<br></span><span class=
"comment">! Settings to make xterm-88c work as expected for Debian.<br>
</span> <span class="comment">!<br></span><span class=
"comment">! Patch #88 was the basis for XFree86 3.3.1 xterm. There were a few additions<br>
</span> <span class=
"comment">! through patch 88c, to incorporate the ptyInitialErase resource. Debian uses<br>
</span> <span class=
"comment">! the VT220-style keyboard, which at #88 was the xterm-xfree86 terminfo entry,<br>
</span> <span class=
"comment">! with one change: kbs changed from ^H to ^?.<br>
</span> <span class="comment">!<br></span><span class=
"comment">! After patch 88, I started work on keyboard changes. The result was that the<br>
</span> <span class=
"comment">! xterm-xfree86 terminfo entry was set to the PC-style keyboard, and I added<br>
</span> <span class=
"comment">! xterm-vt220, which corresponded mostly to the older (patch-88) version of the<br>
</span> <span class=
"comment">! xterm-xfree86 terminfo entry.<br></span> <br>
<span class=
"comment">! The terminfo with patch #88 assumed sunKeyboard was set (actually a bug, but<br>
</span> <span class=
"comment">! also assumed in Debian).<br></span><span class="comment">!<br>
</span> <span class=
"comment">! A different problem (addressed after patch #88) is that if you wanted to use<br>
</span> <span class=
"comment">! a VT100/VT220-style numeric keypad's escape sequences, you had to have<br>
</span> <span class=
"comment">! NumLock set. Otherwise, in keypad application mode, the keys would transmit<br>
</span> <span class=
"comment">! only the PC-style escape sequences corresponding to the key labels, e.g., the<br>
</span> <span class=
"comment">! page-up string rather than the escape sequence for keypad-9.<br>
</span> <span class="keyword">XTerm</span>*<span class=
"ident2">sunKeyboard</span>:<span class=
"literal"> </span><span class="keyword">true</span><br>
<br>
<span class=
"comment">! These settings overlap to some extent (backarrowKeys says to send a 127 for<br>
</span> <span class=
"comment">! the "backspace" key, and ptyInitialErase says to use the pty's initial sense<br>
</span> <span class=
"comment">! of the erase character, which is reported to be the same on Linux).<br>
</span> <span class="keyword">XTerm</span>*<span class=
"ident2">backarrowKey</span>:<span class=
"literal"> </span><span class="keyword">false</span><br>
<span class="keyword">XTerm</span>*<span class=
"ident2">ptyInitialErase</span>:<span class=
"literal"> </span><span class="keyword">true</span><br>
<!--atr2html}}--></p>
</blockquote>
<h4 id="xterm_arrows-id"><a name="xterm_arrows" id=
"xterm_arrows">Why can't I use the cursor keys in (whatever)
shell?</a></h4>
<p>VTxxx (VT100 and up) terminals may send different escape
sequences for the cursor (arrow) keys depending on how they are
set up. The choices are referred to as the normal and application
modes. Initially, the terminal is in normal mode.</p>
<p>VTxxx terminals are usually set up so that full-screen
applications will use the cursor application mode strings. This
is good for full-screen applications, including legacy
applications which may have hard-coded behavior, but bad for
interactive shells (e.g., ksh, tcsh, bash) which use arrow keys
to scroll through a history of command strings.</p>
<p>To see the difference between normal/application modes,
consider this example:</p>
<ul>
<li>In normal (non-application) mode, the terminal transmits a
down-arrow as \E[C, which happens to echo as a down-arrow.</li>
<li>In application mode the terminal transmits \EOC, which
echoes as C. That is because the \EO is the SS3 control, which
says to use the character from the G3 character set for the
next cell.</li>
</ul>
<p>Since termcaps and terminfo descriptions are written for
full-screen applications, shells and similar programs often rely
on built-in tables of escape sequences which they use instead.
Defining keys in terms of the termcap/terminfo entry (e.g., by
capturing the string sent by tputs) is apt to confuse the
shell.</p>
<p>Depending on the terminal type, the keypad(s) on the keyboard
may switch modes along with the cursor keys, or have their own
independent modes. The control sequences for these are
independent of the ones used for cursor-addressing, but are
grouped together, e.g., as the terminfo <code>smkx</code> and
<code>rmkx</code> capabilities. Terminfo entries are written
assuming that the application has initialized the terminal using
the <code>smkx</code> string before it is able to match the codes
given for the cursor or keypad keys.</p>
<h4 id="bash_meta_mode-id"><a name="bash_meta_mode" id=
"bash_meta_mode">Alt-keys do not work in bash</a></h4>
<p>See <a href=
"../ncurses/ncurses.faq.html#bash_meta_mode">Alt-keys do not work
in bash</a>.</p>
<h3 id="problems_colors-id"><a name="problems_colors" id=
"problems_colors">Colors and other graphic rendition</a></h3>
<h4 id="no_color-id"><a name="no_color" id="no_color">My terminal
doesn't recognize color</a></h4>
<p>First, ensure that you have set up xterm to render color.
Modern xterm renders color only if you have set resources to do
this; the default behavior is monochrome to maintain
compatibility with older applications. The manual page describes
these resources. I set them in my <a href=
"xterm.faq.html#my_xdefaults">.Xdefaults</a> file.</p>
<p>Even if you set the resources properly, there may be another
application running which prevents xterm from allocating the
colors you have specified. But you should see a <a href=
"xterm.faq.html#alloc_color">warning message</a> for this.</p>
<p>Check the terminal description, to see if it is installed
properly, e.g., for <a href=
"../ncurses/ncurses.faq.html#no_color">ncurses</a>, which uses
terminfo.</p>
<p>Finally, some applications (that do not interface properly
with terminfo or termcap) may need the environment variable
<a href="../ncurses/ncurses.faq.html#no_colorterm">$COLORTERM</a>
to be set.</p>
<h4 id="xterm_terminfo-id"><a name="xterm_terminfo" id=
"xterm_terminfo">What $TERM should I use?</a></h4>
<p><strong>XTerm</strong> provides in its sources both <a href=
"terminfo.html">terminfo</a> and termcap files. They are designed
to allow scripting to override the most common choices, e.g., the
backspace key.</p>
<p>The <code>xterm-color</code> value for $TERM is a bad choice
for modern xterm because it is commonly used for a terminfo entry
which happens to not support <code>bce</code>. Complicating
matters, FreeBSD (after dithering for a few years on the matter)
introduced a bastardized version which implies the opposite sense
of <code>bce</code>, (because it uses SGR 39 and 49), but does
not set it. After lengthy discussion, FreeBSD began using the
terminal descriptions which I've written.</p>
<p>The most recent XFree86 version's terminal description
corresponds to <code>xterm-xfree86</code> (also distributed with
ncurses). I have continued to make changes; the most recent
version is simply named <code>xterm-new</code> (also distributed
with ncurses).</p>
<p>The term "<code>bce</code>" stands for "back color erase".
Terminals such as modern xterm and rxvt implement back color
erase, others such as dtterm do not. (Roughly half of the
emulators that I know about implement bce). When an application
clears the screen, a terminal that implements back color erase
will retain the last-set background color. A terminal that does
not implement back color erase will reset the background color to
the default or initial colors. Applications that paint most of
the screen in a single color are more efficient on terminals that
support back color erase.</p>
<p>Curses libraries that support color know about
<code>bce</code> and do the right thing – provided that you
tell them what the terminal does. That is the whole point of
setting $TERM. The "xterm-color" description distributed with
ncurses does not list <code>bce</code>, because it was applied
originally to a terminal type which does not implement back color
erase. It will "work" for modern xterm, though less efficient.
Some other applications such as the slang library have hardcoded
support for terminals that implement back color erase. Given the
"xterm-color" description, those will be efficient – and
fortuitously work. However, slang (through version 1.4.0) did not
work properly for the terminals that xterm-color was designed
for. See this <a href="../lynx/lynx-ncurses.html">page</a> for an
example of (n)curses and slang running on dtterm. That bug in
slang is reported to be fixed for succeeding versions, though
your application may require changes to use this fix. (The demo
which comes with slang to illustrate the use of <code>bce</code>
does not work properly, for instance).</p>
<p>The <code>xterm-color</code> value for $TERM is also (for the
same reason) a bad choice for rxvt, but "works" due to the large
number of hard-coded applications that override this.</p>
<p>Some people recommend using <code>xtermc</code>. That is
installed on Solaris. However, it does not match any xterm in
current use. (Apparently it was written for an obsolete version
on Unixware). The colors work, true, but the mouse will not, nor
will the function keys.</p>
<h4 id="xterm_hilite-id"><a name="xterm_hilite" id=
"xterm_hilite">Reverse video is not reset</a></h4>
<p>When running <em>less</em> or other programs that do
highlighting, you see the highlighting not turned off
properly.</p>
<p>This may be due to incompatible terminal descriptions for
xterm. With XFree86 3.2, I modified the terminal description for
XFree86 xterm to use the VT220 (aka ISO 6429) controls that allow
an application to turn off highlighting (or bold, underline)
without modifying the other attributes. The X Consortium xterm
does not recognize these controls.</p>
<p>If, for example, you are running an older xterm and rlogin to
a system where the newer xterm has been installed, you will have
this problem, because both programs default to $TERM set to
xterm. The solution for mixed systems is to install the newer
terminal description as as a different name (e.g.,
<code>xterm-color</code>) and set the <code>termName</code>
resource accordingly in the app-defaults file for the system
which has the newer xterm.</p>
<p>However – see <a href=
"xterm.faq.html#xterm_terminfo">above</a>.</p>
<h4 id="vim_16colors-id"><a name="vim_16colors" id=
"vim_16colors">My colors changed in vim</a></h4>
<p>Some <code>vim</code> users may notice their colors change
after updating to <a href="xterm.log.html#xterm_238">patch
238</a>. Before, some text would display in a dark color using a
bold font. Now, it displays in a bright color and normal
font.</p>
<p>This is not a bug, but the result of a feature
<em>tcap-query</em> which was added for vim in 2000. Several vim
users requested that it be enabled by default in the configure
script. It allows vim to ask what characters the different
function keys actually send, eliminating the chance that the
termcap does not match.</p>
<p>Vim also asks how many colors the terminal supports. Since
<a href="xterm.log.html#xterm_148">patch 148</a>, xterm has
responded with the number of distinct colors that it can display.
By default, that is 16 (8 ANSI colors with bright counterparts
for displaying PC-style "bold" text).</p>
<p>The interpretation of this depends on the application:
termcaps do not tell how to display more than 8 colors. But vim
understands how to tell xterm to display using 16 colors. It
makes a difference when displaying bright colors. Vim has a table
of 16 color names ("dos-colors"), which one can use to define
parts of the color scheme. If the terminal supports only 8 colors
(colors 0-7), vim uses the bold attribute to simulate colors
8-15.</p>
<p>Changing the color scheme to use bold where it is wanted will
make the colors work as before – and work consistently with
other terminals.</p>
<h4 id="bold_vs_16colors-id"><a name="bold_vs_16colors" id=
"bold_vs_16colors">Aren't bright colors the same as
bold?</a></h4>
<p>No.</p>
<p>Actually, "bold" happens to be whatever the terminal shows
when it is sent the control-string that says "show bold".</p>
<p>The standard (ANSI aka ISO-6429 or ECMA-48) says no more than
that. ANSI specified eight (8) colors. In fact, ANSI did not
specify the appearance. That is an implementation detail.</p>
<p>XTerm can be configured to use colors 8-15 for displaying bold
text. Or it can be configured to use those colors as part of a
16-color scheme (a feature of aixterm). They use different
control strings. When xterm is configured to use the 16-color
scheme, it displays bold text by relying on the font to show
"bold" (usually thicker characters).</p>
<p>By default, colors 8-15 are brighter versions of colors 0-7
(with some special handling for blue). But again, xterm is
configurable and you can use anything that you like for the
numbered colors.</p>
<h4 id="dont_like_blue-id"><a name="dont_like_blue" id=
"dont_like_blue">I don't like that shade of blue</a></h4>
<p>Nobody does. But there are no universal solutions.</p>
<p>If your terminal (or the application running in it has a dark
background, then darker blues are hard to see. With a light
background, yellows are hard to see.</p>
<p>The available standards do not help: there <em>are</em> no
standards for terminal colors. Here is an illustration which I
made in reply to a <a href=
"http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=241717">bug
report</a>, contrasting different choices for blue, against some
of the other terminals which (were said to) provide "standard
vt100 colors":</p>
<blockquote>
<p><a href="images/contrast.jpg"><img width="450" src=
"images/contrast.jpg" alt=
"Contrasting blue in terminal emulators"></a></p>
</blockquote>
<p>Of course, anyone <em>developing</em> a terminal emulator
already knew that <a href=
"../ncurses/ncurses.faq.html#vt100_color">vt100's never did do
colors</a>.</p>
<p>Ultimately it is up to the application running in a terminal
to enforce the colors it needs. XTerm merely provides the best
compromise on default visibility that I and my users have
found.</p>
<h4 id="why_no_italics-id"><a name="why_no_italics" id=
"why_no_italics">Why doesn't xterm support italics?</a></h4>
<p>Well, actually it does and it doesn't.</p>
<p>You can display "any" font using xterm (though proportional
fonts may be disappointing).</p>
<p>But xterm has specific types of graphic rendition that it will
do. If you want italics, then xterm has an option
(<code>italicULMode</code>) to use that rendition instead of
underlining. That is the usual typographic alternative, though of
course some people want both at the same time.</p>
<p>However, curses does not support italics. Few terminals do
this reliably, so it was disregarded long ago, never was
standardized except for low-level applications (in terminfo). No
bit was reserved in the curses header for adding italics for
high-level applications. (As a special case, ncurses could be
modified to do this, but other implementations would not
work).</p>
<p>XTerm stores each cell of the display in fixed-size
structures. One byte stores the graphic rendition. XTerm is using
all of the bits in this byte for its VT220 emulation:</p>
<table border="1" summary="Bits for XTerm's graphic rendition">
<tr>
<th>Mnemonic</th>
<th>Bit</th>
<th>Description</th>
</tr>
<tr>
<td>INVERSE</td>
<td>0</td>
<td>show cell reverse-video</td>
</tr>
<tr>
<td>UNDERLINE</td>
<td>1</td>
<td>show cell underlined</td>
</tr>
<tr>
<td>BOLD</td>
<td>2</td>
<td>show cell as bold</td>
</tr>
<tr>
<td>BLINK</td>
<td>3</td>
<td>show cell as blinking</td>
</tr>
<tr>
<td>BG_COLOR</td>
<td>4</td>
<td>use background color</td>
</tr>
<tr>
<td>FG_COLOR</td>
<td>5</td>
<td>use foreground color</td>
</tr>
<tr>
<td>PROTECTED</td>
<td>6</td>
<td>character cannot be erased</td>
</tr>
<tr>
<td>CHARDRAWN</td>
<td>7</td>
<td>character has been drawn here on the screen</td>
</tr>
</table>
<p>While additional bytes could be added to each cell, the cost
to the typical user has so far not been in line with the
usefulness of the feature.</p>
<h4 id="grep_colors-id"><a name="grep_colors" id=
"grep_colors">"grep --color" does not show the right
output</a></h4>
<p>GNU grep (version 2.5) introduced a <code>--color</code>
option.</p>
<p>It does this for each highlighted match:</p>
<ol>
<li>it writes the text up to (not including the match)</li>
<li>it writes an ANSI color control control sequence</li>
<li>it writes the matched text</li>
<li>it writes a control sequence to clear to the end of the
line</li>
<li>it writes an ANSI control sequence to reset graphic
rendition.</li>
<li>repeat this process until the entire line is written.</li>
</ol>
<p>One problem is in the second and fourth steps. If the
preceding text brought us up to the last column, then xterm (and
any VT100-compatible terminal) is waiting for graphic text to
wrap to the next line. Any controls would take effect on the
current column position. Newlines are ignored while in this
state.</p>
<p>However, if xterm gets a control sequence while waiting to
wrap to the next line, it will update the screen according to
that control. Then it is ready to accept more data. But at this
point, it is no longer waiting to wrap; the special case is for
newline versus graphic characters. For instance, backspacing
clears the state (<a href="../vttest/vttest.html">vttest</a>
illustrates this). So the data starts to write at the current
column (the last one on the line), rather than at the beginning
of the next line. In that case, grep's output will not look
right.</p>
<h4 id="vt100_wrapping-id"><a name="vt100_wrapping" id=
"vt100_wrapping">That description of wrapping is odd, say
more?</a></h4>
<p>This is one of the aspects of the so-called "vt100 glitch", as
mentioned in the terminfo manpage:</p>
<blockquote>
<p>Terminals which ignore a line-feed immediately after an am
wrap, such as the Concept and vt100, should indicate xenl.</p>
</blockquote>
<p>When the terminal reaches the right margin, it is in a special
state where it ignores tab characters and other formatting
controls (carriage return and newline), and in effect is
expecting only printable characters to wrap to the next line.</p>
<p>Without it, it is misleading to refer to a terminal as a vt100
emulator. After all, it is a well-known feature named for the
VT100. The applicable standards (ISO-6429, ECMA-48) do not go
into enough detail to address this sort of behavior, so the other
terminal emulators can be referred to most accurately as ANSI
terminals (if they obey the other guidelines).</p>
<p><a href="../vttest/CHANGES">In 2004</a>, I added a test-screen
to vttest to demonstrate this. It was in response to someone who
insisted that xterm was wrong and one of those other terminal
emulators was "right". I investigated, found that the behavior
had not changed in xterm at least since the early 1990s, and that
it matched the description of behavior from the DEC manuals. One
of my users verified the correctness of the test on a VT520.</p>
<p>Reviewing the results with xterm-alikes or less ambitious
"vt100 emulators" in mid-2012:</p>
<ul>
<li>xterm, kterm, mlterm, rxvt are consistent with the VT100
behavior.</li>
<li>screen, putty (pterm), konsole, vte (gnome-terminal),
xfce4-terminal are not consistent with VT100 (and behave
differently compared to each other).
<p>I included screen here because it claims to be a vt100
emulator, and putty since it claims to be an xterm emulator.
I did not include tmux, because it does not make either
claim.</p>
</li>
<li>mrxvt does not get to that screen; it resizes its window to
a single line.</li>
</ul>
<h3 id="problems_weird-id"><a name="problems_weird" id=
"problems_weird">Odd behavior</a></h3>
<h4 id="xterm_paste-id"><a name="xterm_paste" id=
"xterm_paste">Why can't I cut/paste in xterm?</a></h4>
<p>When an application sets xterm to any of its mouse tracking
modes, it reserves the unshifted mouse button clicks for the
application's use. Unless you have modified the treatment of the
shifted mouse button events (e.g., with your window manager), you
can always do cut/paste by pressing the shift key while clicking
with the mouse.</p>
<h4 id="xterm_tabs-id"><a name="xterm_tabs" id="xterm_tabs">Why
can't I select tabs in xterm?</a></h4>
<p>This issue was noted early on, <a href=
"xterm.faq.html#known_bugs">here</a> in 1997.</p>
<p><strong>XTerm</strong> is copying from the screen, which
stores only printable characters. That includes spaces and
line-drawing characters. But tabs are special; they are used for
more than one purpose.</p>
<p>If the screen is cleared in some part, that stores nulls.
Cursor addressing does not fill in nulls as it jumps around,
though xterm does supply blanks for the most useful cases,
especially when getting data for a selection.</p>
<p>Full-screen programs such as text-editors tend to write in
random fashion, and generally do not print nulls to the screen.
Curses on the other hand, may supply tabs where you thought there
were none. Also, the terminal driver can expand tabs (and often
is set to do this by default).</p>
<p>So the whole thing is unreliable: unless you make special
arrangements for each of the programs running inside xterm, you
would often get a tab when you expect, and vice versa.</p>
<p>For the special case where your expectations would match the
available data, it is solvable. There are basically two ways it
could be done:</p>
<ul>
<li>set a bit in each cell's data which says it was skipped
over via a tab. The complication is that xterm is using all of
the flag bits in each cell.</li>
<li>store literal tabs and nulls to be interpreted later
– both by the display and the selection logic.</li>
</ul>
<p>As of 2010, a few other terminals do implement this feature.
But the reason that it's been low-priority is that it's of very
limited usefulness when copying between terminal sessions (and
for that matter, from other clients).</p>
<h4 id="xterm_resize-id"><a name="xterm_resize" id=
"xterm_resize">FVWM does weird things when I try to resize
xterm</a></h4>
<p>I have an old (3.1.2G) bug report for xterm which may be
related to the second (3.9s) problem:</p>
<ul>
<li>Steven Lang <tiger@ecis.com> reports a problem with
extra resize events for xterm.
<p>When I change font size often I will get the
double-refresh, and when that happens the text program gets 2
resize events.. Running a quick test, I got this: Going to a
bigger font, it got a 53x20 resize, then a 80x24 resize.
Going to a smaller font, it got a 120x27 resize, then a 80x24
resize.</p>
<p>Earlier I made a mention of changing font size in rxvt
(And xterm does it to) causing 2 resize events. Well I just
happened to do it in fvwm (Instead of fvwm 95) and found it
seems to be a 'feature' of fvwm95, not XFree86 as I'd
initially assumed.</p>
</li>
<li>Stephen Marley <stephen@memex.com> reports a problem
with the active icon (from X11R6.3 xterm):
<p>Using the XFree86 xterm-53 with the active icon feature
on, I get some problems resizing where the xterm window
shrinks as small as possible and won't stay at whatever size
you set it thereafter.</p>
<p>Comment out the PixmapPath and IconPath from your .fvwmrc
file to disable the fvwm icons and restart the WM. Start an
xterm. Iconify xterm and maximize it again. Use resize button
or corners to resize the xterm.</p>
<p>The xterm now shrinks to a tiny size and attempts to
resize it result in it shrinking again.</p>
<p>I've tried this with fvwm 1.23 and fvwm 2.0.46 with the
same results. Olvm, olvwm and twm all behave correctly so it
may be a fvwm problem.</p>
</li>
</ul>
<p>I have not observed the first, but have reproduced the
second.</p>
<h4 id="xterm_tite-id"><a name="xterm_tite" id="xterm_tite">Why
doesn't the screen clear when running vi?</a></h4>
<p>This refers to the "alternate screen" feature, which has been
used in its termcap file since 1988. On various systems, this
feature may have been removed, although it has always been in the
xterm sources.</p>
<p>The feature is controllable (it can be enabled or disabled).
However, as it was originally conceived, that ability to control
it applies only to programs using termcap.</p>
<p>Under SunOS 4.x, the termcap description for xterm embeds in
the <code>ti</code> and <code>te</code> capabilities a command to
switch to xterm's alternate screen (e.g., while running
<code>vi</code>), and return to the normal screen on exit. This
has the effect of clearing the screen. Under Solaris 2.x, the
terminfo description does not use the alternate screen (it is a
matter of preference after all), so that the text from vi remains
on the screen after exit. There are corresponding terminfo
symbols for <code>ti</code> and <code>te</code>:
<code>smcup</code> and <code>rmcup</code>, respectively.</p>
<p>This is configurable...</p>
<p>For example (from Bjorn Helgaas <helgaas@dhc.net>) this
procedure adds these capabilities to the "xterm" terminfo
definition on HP-UX 10.20:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
cp /usr/lib/terminfo/x/xterm /usr/lib/terminfo/x/xterm.orig<br>
untic xterm > /tmp/xterm.src<br>
<span class="keyword">echo</span> <span class=
"literal">" smcup=</span><span class=
"keyword2">\</span><span class="literal">E7</span><span class=
"keyword2">\</span><span class=
"literal">E[?47h, rmcup=</span><span class=
"keyword2">\</span><span class=
"literal">E[2J</span><span class="keyword2">\</span><span class="literal">E[?47l</span><span class="keyword2">\</span><span class="literal">E8,"</span> >> /tmp/xterm.src<br>
tic /tmp/xterm.src<br>
<!--atr2html}}--></p>
</blockquote>
<p>In this example, the terminfo strings are a series of
operations:</p>
<dl>
<dt><code>smcup</code></dt>
<dd><code>\E7</code> saves the cursor's position</dd>
<dd><code>\E[?47h</code> switches to the alternate screen</dd>
<dt><code>rmcup</code></dt>
<dd><code>\E[2J</code> clears the screen (assumed to be the
alternate screen)</dd>
<dd><code>\E[?47l</code> switches back to the normal
screen</dd>
<dd><code>\E8</code> restores the cursor's position.</dd>
</dl>
<p>However, xterms that are linked with termcap are more flexible
in this area than those linked with terminfo libraries. The xterm
program supports a resource <code>titeInhibit</code> which
manipulates the $TERMCAP variable to accomplish this. It sets the
$TERMCAP variable for the client with the <code>ti</code> and
<code>te</code> capabilities suppressed. Systems that use
terminfo cannot do this. If you are running terminfo with the
alternate screen controls in the terminal description, then you
can suppress the switching to the alternate screen by the
<code>titeInhibit</code>, but not the associated cursor
save/restore and clear-screen operations.</p>
<p>XFree86 3.9s xterm implements a different set of controls
(private setmodes 1047, 1048 and 1049) which address this (in
addition to the older set of controls, for compatibility). The
new set of controls implements the entire <code>ti</code>
sequence (save cursor, switch to alternate screen, clear screen)
and <code>te</code> (switch to normal screen, restore cursor) as
two control sequences that can be disabled by
<code>titeInhibit</code>.</p>
<p>The 1049 code is a refinement of 1047 and 1048, clearing the
alternate screen before switching to it rather than after
switching back to the normal screen. Since <a href=
"xterm.log.html#xterm_90">patch #90 in 1998</a> xterm allows you
(with a popup menu entry designed to exploit this behavior) to
switch the display back to the alternate screen to select text
from it, to paste into the normal screen. You can also set or
clear the <code>titeInhibit</code> resource using another popup
menu entry (<code>Enable Alternate Screen Switching</code>).</p>
<p>Most other terminal emulators implement only half of the
feature. They recognize the control sequence, but do not provide
the ability to change it at runtime, e.g., using a menu entry.
Like any other half-done implementation, that is a bug which
should be reported to the developers of those programs.</p>
<h4 id="xterm_vite-id"><a name="xterm_vite" id="xterm_vite">Why
is the cursor misplaced after running vi?</a></h4>
<p>Vi and other full-screen applications use the termcap
<code>ti/te</code> (terminfo <code>smcup/rmcup</code>) strings to
initiate and end cursor addressing mode. As mentioned in the
discussion of <a href=
"xterm.faq.html#xterm_tite">titeInhibit</a>, full-screen
applications can expect the initialization string to save the
cursor's position, and the end-string to restore it.</p>
<p>A few applications (reportedly IRIX 5.x and 6.x
<code>vi</code> incorrectly move the cursor before initializing
cursor-addressing. This will cause the end-string to restore the
cursor to its position when it was saved by the initialization
string (typically at the upper left corner of the screen).</p>
<p>The usual reason is due to the cursor save/restore controls in
the <code>ti/te</code> strings. If your application runs a
subprocess which in turn runs another full-screen application (or
when reinitializing the screen after the shell process), it will
save the cursor position again, so the position which is restored
when finally exiting your program is the last one saved, not the
first. Modern xterm (from late 1998, <a href=
"xterm.log.html#xterm_90">patch 90</a>) changes the behavior of
the cursor save/restore operations so they apply only to the
current screen. That makes it less likely to misplace your
cursor.</p>
<h4 id="narrowproto-id"><a name="narrowproto" id=
"narrowproto">Why doesn't the scrollbar work?</a></h4>
<p>Originally xterm was built using imake rather than a configure
script. One feature of imake that is not possible to guess within
the configure script is the wide-prototype compile-time
definition NARROWPROTO. When this is not set properly, the Athena
widget scrollbars do not work properly. xterm's configure script
has a fallback case which allows disabling imake. However, this
is moot with the Xorg "modular" build, whose compiler options are
unrelated to imake or older versions of any libraries that it may
distribute. In this case, the configure script needs some help.
Use this option to enable or disable NARROW proto (and disable
imake with the --disable-imake option) to match the whims of Xorg
hackers.</p>
<p>For instance</p>
<blockquote>
<pre>
<code>configure --disable-imake --disable-narrowproto</code>
</pre>
</blockquote>
<h4 id="window_ops-id"><a name="window_ops" id="window_ops">Why
can't my program read the window title?</a></h4>
<p>The longstanding control sequence for reading the window title
is something that can be abused in special conditions. For novice
(unknowledgable) users, this can be a problem.</p>
<p><strong>XTerm</strong> provides resource-settings and menu
entries to allow this and related features to be enabled or
disabled. See for example <code>allowWindowOps</code> The default
resource settings in xterm can be overridden by a packager.
However, a knowledgable user can override those default
settings.</p>
<p>It is also possible that an overzealous packager may have
crippled xterm by removing the functionality altogether. (That
should be reported as a bug, to me).</p>
<p>For instance, one of those sent me a "security fix" some years
ago, which deleted most of the control sequences which return
data to the host. It broke the <code>resize</code> program, and
selection, among other uses considered to be benign. In contrast,
the same features used in other terminal emulators are tolerated
by the same people, so rather than being a misguided attempt at
fixing security issues, patches such as that appear to be an
attempt at harassment.</p>
<h4 id="window_ops2-id"><a name="window_ops2" id=
"window_ops2">Why can't my program set the window size?</a></h4>
<p>Some overzealous packagers, perhaps influenced by the
demonstration I provided, are protecting you against the
possibility of your xterm becoming inaccessible. (That's
unlikely...).</p>
<p>You should be able to override it, as noted above via resource
settings or menu entry ("Allow Window Ops").</p>
<h4><a name="compiz_bugs" id="compiz_bugs">Why is the text in the
wrong place?</a></h4>
<p>Are you using Ubuntu? This is a frequently-reported problem
for Ubuntu users. With other systems, it can occur (as of
September 2012), but is less frequent. But it has been an issue
with Ubuntu since 2008.</p>
<p>There are several related symptoms, e.g.,</p>
<ul>
<li>text may be the wrong size</li>
<li>repainting the screen puts text in the wrong place</li>
</ul>
<p>Here are some of the corresponding bug reports:</p>
<ul>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/xterm/+bug/199285">Ubuntu
#199285 - xterm crashes when compiz is on</a></li>
<li><a href=
"http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=467399">Debian
#467399 - compiz fails to take control of windows</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/xfce4-terminal/+bug/378668">
Ubuntu #378668 - Cursor in terminal behaves badly with special
characters present</a></li>
<li><a href=
"https://bugzilla.novell.com/show_bug.cgi?id=622936">Novell
#622936 - xterm: font drawing glitch</a></li>
<li><a href=
"https://bugzilla.redhat.com/show_bug.cgi?id=583904">Redhat
#583904 - gnome-terminal and xterm show garbled fonts with
compiz enabled (intel graphics)</a></li>
<li><a href=
"https://bugzilla.redhat.com/show_bug.cgi?id=614542">Redhat
#614542 - xterm graphical corruption when compiz is
active</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/635258">Ubuntu
#635258 - Garbled chars in xterm</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/644943">Ubuntu
#644943 - xterm fonts get corrupted while typing</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/701160">Ubuntu
#701160 - /usr/bin/xterm is not functional in natty</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/xterm/+bug/700477">Ubuntu
#700477 - Font corruption in xterm under Lucid</a></li>
<li><a href=
"https://bugzilla.novell.com/show_bug.cgi?id=681359">Novell
#681359 - xterm: no data shown under the screen
program</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/711894">Ubuntu
#711894 - iconic option does not work with compiz</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/xterm/+bug/778439">Ubuntu
#778439 - Typing "exit" in xterm kills X session</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/831336">
Ubuntu #831336 - running 'xterm' crashes X server</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/841103">Ubuntu
#841103 - Text has artifacts when typing something
else</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/844454">Ubuntu
#844454 - Garbled chars in xterm (Onieric)</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/1002972">
Ubuntu #1002972 - xterm moves to upper left when clicking titel
bar</a></li>
<li><a href=
"https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/1007722">
Ubuntu #1007722 - xterm doesn't display all the
information</a></li>
</ul>
<p>Since the problem is not in xterm, all I can do is to help
forward those bug-reports to whatever package owns
<code>compiz</code>. What these have in common is that someone
has written code which is tested against only a small subset of
the X protocol.</p>
<p>Looking for solutions (since compiz is not being fixed), it is
possible to disable compiz. The means for doing this vary with
time. Aside from pointing to the root cause of the problem, there
is little advice that is useful.</p>
<ul>
<li>For instance, <a href=
"http://www.subcritical.org/xterm_under_compiz/">this
comment</a> by Eric Williams suggests that the problem can be
worked around by setting xterm's <code>borderWidth</code>
resource to zero.</li>
<li>other comments suggest turning off the "desktop effects" or
"animation".</li>
<li>On my machines using the default <em>Ubuntu</em> desktop, I
can see misbehavior easily in Ubuntu 12.04 using <a href=
"../vttest/vttest.html">vttest</a>. However, Ubuntu 12.04
provides <em>Ubuntu 2D</em>, which does not show those
problems (and is noticeably faster).</li>
</ul>
<h3 id="my_xdefaults-id"><a name="my_xdefaults" id=
"my_xdefaults">Sample .Xdefaults Color-Settings for
XTerm</a></h3>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"ident2">internalBorder</span>:<span class=
"literal"> </span><span class="number">10</span><br>
<span class="keyword">XTerm</span>*<span class=
"ident2">highlightSelection</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorBDMode</span>:<span class=
"literal"> on</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorBD</span>:<span class=
"literal"> blue</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorULMode</span>:<span class=
"literal"> on</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorUL</span>:<span class=
"literal"> magenta</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">eightBitInput</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">eightBitOutput</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
<span class="keyword">XTerm</span>*<span class=
"ident2">scrollBar</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">titeInhibit</span>:<span class=
"literal"> </span><span class=
"keyword">true</span><br>
<br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorMode</span>:<span class=
"literal"> on</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">dynamicColors</span>:<span class=
"literal"> on</span><br>
<br>
<span class=
"comment">! Uncomment this to use color for underline attribute<br>
</span> <span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorULMode</span>:<span class=
"literal"> on</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">underLine</span>:<span class=
"literal"> off</span><br>
<br>
<span class=
"comment">! Uncomment this to use color for the bold attribute<br>
</span> <span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorBDMode</span>:<span class=
"literal"> on</span><br>
<br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color0</span>:<span class=
"literal"> black</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color1</span>:<span class=
"literal"> red3</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color2</span>:<span class=
"literal"> green3</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color3</span>:<span class=
"literal"> yellow3</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color4</span>:<span class=
"literal"> blue3</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color5</span>:<span class=
"literal"> magenta3</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color6</span>:<span class=
"literal"> cyan3</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color7</span>:<span class=
"literal"> gray90</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color8</span>:<span class=
"literal"> gray30</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color9</span>:<span class=
"literal"> red</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color10</span>:<span class=
"literal"> green</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color11</span>:<span class=
"literal"> yellow</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color12</span>:<span class=
"literal"> blue</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color13</span>:<span class=
"literal"> magenta</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color14</span>:<span class=
"literal"> cyan</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">color15</span>:<span class=
"literal"> white</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorUL</span>:<span class=
"literal"> yellow</span><br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">colorBD</span>:<span class=
"literal"> white</span><br>
<br>
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">cursorColor</span>:<span class=
"literal"> lime green</span><br>
<!--atr2html}}--></p>
</blockquote>
<p><strong>XTerm</strong> comes with two copies of each resource
file, one with color only (<code>XTerm-col.ad</code>, which is
installed as <code>XTerm-color</code>), and the regular one
(<code>XTerm.ad</code>, installed as <code>XTerm</code>). To use
the <code>XTerm-color</code> file in conjunction with a separate
<code>XTerm</code> app-defaults file which does not contain
color, add the following line to your <code>.Xdefaults</code>
file:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
*<span class="ident2">customization</span>:<span class=
"literal"> -color</span><br>
<!--atr2html}}--></p>
</blockquote>
<h3 id="warning_msg-id"><a name="warning_msg" id=
"warning_msg">What is this warning message?</a></h3>
<dl>
<dt id="warning_errno">xterm: Error 11, errno 22: permission
denied</dt>
<dd>
Actually, any message like this denotes a failure which
requires studying the xterm source to determine the exact
problem.
<p>You have either found a bug in xterm, or there is
something wrong with your computer's configuration, e.g., not
enough pty's, incorrect permissions, etc.</p>
<p>The first number is an internal code (defined in error.h
in xterm's source), and the second is the system error number
(defined in /usr/include/sys/errno.h). The system error
number is easier to lookup, but the internal error code tells
you where to look in the source.</p>
</dd>
<dt id="warning_preedit">input method doesn't support my
preedit type</dt>
<dd>
Ignore this if you do not know what <em>input method</em> is.
Input methods are used to enter composite characters (e.g.,
umlauts, other types of punctuated characters, East Asian
characters, etc). Your computer's libraries support this, but
are missing configuration tables, and xterm is warning you.
<p>If the message bothers you (e.g., if you aren't starting
xterm from a window manager menu), you can suppress it by
setting a resource:</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"ident2">openIm</span>:<span class=
"keyword">false</span><br>
<!--atr2html}}--></p>
</blockquote>
</dd>
<dt id="warning_action">Warning: Actions not found: ignore,
"xxx"</dt>
<dd>
The action "xxx" (for example "scroll-back") is specified in
a resource file whose translations match widgets that do not
support them. For example, this
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"ident2">translations</span>:<span class=
"literal"> #override\n\<br>
</span><span class="keyword"><Leave></span><span class="literal">, ~Ctrl ~Meta </span><span class="keyword"><Btn2Up></span><span class="literal">: ignore()\n\<br>
~Shift </span><span class="keyword"><Key></span><span class="literal">KP_8: scroll-back(</span><span class="number">1</span><span class="literal">,line)\n\<br>
~Shift </span><span class="keyword"><Key></span><span class="literal">KP_2: scroll-forw(</span><span class="number">1</span><span class="literal">,line)\n\<br>
Shift </span><span class="keyword"><Key></span><span class="literal">KP_8: scroll-back(</span><span class="number">1</span><span class="literal">,halfpage)\n\<br>
Shift </span><span class="keyword"><Key></span><span class="literal">KP_2: scroll-forw(</span><span class="number">1</span><span class="literal">,halfpage)</span><br>
<!--atr2html}}--></p>
</blockquote>
<p>will produce warnings such as</p>
<blockquote>
<pre>
Warning: Actions not found: ignore, scroll-back, scroll-forw
Warning: Actions not found: ignore, scroll-back, scroll-forw
Warning: Actions not found: ignore, scroll-back, scroll-forw
</pre>
</blockquote>
<p>This is a correct form, assigning the actions to the
"VT100" widget.</p>
<blockquote>
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<span class="keyword">XTerm</span>*<span class=
"keyword">VT100</span>.<span class=
"ident2">translations</span>:<span class=
"literal"> #override\n\<br>
</span><span class="keyword"><Leave></span><span class="literal">, ~Ctrl ~Meta </span><span class="keyword"><Btn2Up></span><span class="literal">: ignore()\n\<br>
~Shift </span><span class="keyword"><Key></span><span class="literal">KP_8: scroll-back(</span><span class="number">1</span><span class="literal">,line)\n\<br>
~Shift </span><span class="keyword"><Key></span><span class="literal">KP_2: scroll-forw(</span><span class="number">1</span><span class="literal">,line)\n\<br>
Shift </span><span class="keyword"><Key></span><span class="literal">KP_8: scroll-back(</span><span class="number">1</span><span class="literal">,halfpage)\n\<br>
Shift </span><span class="keyword"><Key></span><span class="literal">KP_2: scroll-forw(</span><span class="number">1</span><span class="literal">,halfpage)</span><br>
<!--atr2html}}--></p>
</blockquote>
</dd>
<dt id="alloc_color-id"><a name="alloc_color" id=
"alloc_color">Warning: Cannot allocate colormap entry for
"xxx"</a></dt>
<dd>
This comes from the X library. Modern xterm uses the default
color map. What this means is that if your X server has
insufficient space to store color information for more than
one color map, other applications which could use other color
maps may conflict with xterm. In practice, that is 256 unique
colors on the screen at a time—not enough for a fancy
background or an application such as Netscape.
<p>During resource initialization, xterm attempts to allocate
an entry from the color map for each color which it might
use. If there are not enough free slots in the color map, you
will see a "Cannot allocate" message for each color that
xterm failed to allocate. Those colors will be rendered in
the foreground color, making full-screen color applications
such as <a href="../dialog/dialog.html">dialog</a>
unreadable.</p>
<p>This problem is alleviated with <a href=
"xterm.log.html#xterm_129">patch 129</a>, which modified
xterm to delay the most color allocation until the colors are
first needed. If a color is never needed (xterm allocates 20
colors in this manner), that reduces the number of slots in
the color map that are needed. Even with this improvement,
xterm must still allocate 4 colors during initialization to
determine how to display the cursor. If none of those colors
can be allocated, xterm reverts to monochrome.</p>
</dd>
</dl>
<h2 id="known_bugs-id"><a name="known_bugs" id="known_bugs">Known
Bugs in <strong>XTerm</strong> and Look–alikes</a></h2>
<p>These are the known bugs (or limitations) in modern xterm.
They are also present in the other versions based on the X
Consortium sources (color_xterm, ansi_xterm, kterm).</p>
<p>Note that of the emulators that support color, some do not
support <code>bce</code> (back color erase). The bce capability
is also called the "new color model", though it has been
implemented in the IBM PC for quite a while. Technically, not
implementing <code>bce</code> (or allowing the choice between it
and its complement) is not a bug, since few hardware terminals
(with good reason) implemented this feature.</p>
<ul>
<li>cut/paste does not <a href=
"xterm.faq.html#xterm_tabs">select tabs</a>; instead spaces are
selected. This is because the selection works from the array of
displayed characters, on which tab/space conversion has already
been performed.</li>
<li>does not implement the autorepeat feature of VTxxx
terminals.</li>
</ul>
<h3 id="bug_xterm_r6-id"><a name="bug_xterm_r6" id=
"bug_xterm_r6">X11R6.3 <strong>XTerm</strong></a></h3>
<p>The X Consortium version of xterm (and versions based on it)
has additional bugs not in modern xterm:</p>
<ul>
<li>the program must be run with fixed (nonproportional)
fonts.</li>
<li>the home and end keys do not generate usable escape
sequences, due to an indexing error. (Note that it is possible
to work around this using the VT100 translations resource, but
usually this is not done).</li>
<li>the Main Options menu is improperly constructed, due to
incorrect indices after removing the logging toggle. This makes
the list of signals off by one.</li>
<li>very large screens (e.g., by using nil2 for a font) cause
core dumps because the program uses a fixed array (200 lines)
for adjusting pointers.</li>
<li>certain types of key translations cause a core dump because
the program does not check the event class before attempting to
use events.</li>
</ul>
<p>(These bugs are also present in the X11R5 version).</p>
<p id="xterm-xorg">Update 2004/04/08:<br>
Complicating this discussion is the "X.Org" xterm (from 2004).
That is the XFree86 xterm from XFree86 CVS with all visible
"xfree86" strings changed to "X.Org" or "xorg", depending on the
use. For example the "xterm-xfree86" terminfo entry becomes
"xterm-xorg". The change history for the related CVS for X.Org
shows this. Similarly, the release notes for X11R6.7 included my
notes for XFree86 4.4.</p>
<p>As of 2009, it appears that "X.Org" xterm died a natural
death, since none of the people who created it had any likelihood
of maintaining it. Instead, X.Org defers to my version of
xterm.</p>
<h3 id="bug_color_xterm-id"><a name="bug_color_xterm" id=
"bug_color_xterm">COLOR_XTERM</a> <a href=
"ftp://ftp.x.org/contrib/applications/color_xterm-beta1.tar.gz">download</a></h3>
<p>This is based on the X Consortium X11R5 source, with the same
bugs.</p>
<ul>
<li>implements non-bce color model</li>
<li>moving the cursor is reported to leave trails of incorrect
color</li>
<li>clearing the screen resets colors (arguably this is a
limitation).</li>
</ul>
<p>Not exactly a bug, but it does not build on Linux with
X11R6.3</p>
<h3 id="bug_ansi_xterm-id"><a name="bug_ansi_xterm" id=
"bug_ansi_xterm">ANSI_XTERM</a> <a href=
"ftp://ftp.x.org/contrib/applications/xterm-R6-sb_right-ansi-3d.tar.gz">
download</a></h3>
<p>This is based on the X Consortium source, with the same
bugs.</p>
<ul>
<li>implements non-bce color model</li>
<li>fails <a href="../vttest/vttest.html">vttest</a> by not
rendering reverse-video screen</li>
</ul>
<h3 id="bug_cxterm-id"><a name="bug_cxterm" id=
"bug_cxterm">CXTERM</a> <a href=
"ftp://ftp.cuhk.hk/pub/chinese/ifcss/software/x-win/cxterm/">download</a></h3>
<p>CXterm stands for "Chinese Xterm". This is based on the X
Consortium source.</p>
<h3 id="bug_dtterm-id"><a name="bug_dtterm" id=
"bug_dtterm">DTTERM</a></h3>
<p>This is distributed with CDE. It implements more of the DEC
VT220 than the X Consortium xterm, and also adds controls to
manipulate the window and icon.</p>
<ul>
<li>implements non-bce color model</li>
<li>fails <a href="../vttest/vttest.html">vttest</a> by
clearing its background to solid white rather than preserving
its sense in response to ED.</li>
<li>under some circumstances, scrolling margins are not
recognized. For instance, running <a href=
"../vile/vile.html">vile</a> which uses scrolling margins, we
see text overwriting the status line.</li>
</ul>
<h3 id="bug_emu-id"><a name="bug_emu" id="bug_emu">EMU 1.3</a>
<a href=
"ftp://ftp.x.org/contrib/applications/emu-1.31.tar.gz">download</a></h3>
<p>This is not based on the X Consortium source. The authors
state that it implements VT220 emulation. It is in need of
maintenance, since it builds with some problems to produce an
executable that (on Linux and SunOS) does not handle the carriage
return and newline translations properly. So I am unable to run
<a href="../vttest/vttest.html">vttest</a> on this emulator.</p>
<h3 id="bug_eterm-id"><a name="bug_eterm" id=
"bug_eterm">ETERM</a> <a href=
"http://www.eterm.org/">link</a></h3>
<p>Eterm was based on rxvt, though the appearance differs. The
terminal emulation capabilities appear similar, though I am not
able to run the full suite of tests in <a href=
"../vttest/vttest.html">vttest</a> with this emulator (the core
dump noted for rxvt, as well as hanging while awaiting response
from one or more control sequences). Oddly, it appears that
neither Eterm nor rxvt implement CPR (cursor position report).
Finally, it reserves F1 (function-key) for a popup menu. This
applies to versions of <em>Eterm</em> through 0.9.</p>
<h3 id="bug_gnometerm-id"><a name="bug_gnometerm" id=
"bug_gnometerm">GNOME TERMINAL</a> <a href=
"http://www.gnome.org/">link</a></h3>
<p>GNOME Terminal is developed separately from both xterm and
rxvt, and was originally based on the zvt (zterm) widget. Like
<a href="xterm.faq.html#bug_kvt">kvt</a>), it appears to have
been developed imitating other terminal emulators (Linux console
and xterm) rather than strictly emulating a VT102. The
documentation is fragmentary (with a comment suggesting that the
author does not know where to find relevant information), and the
program fares badly with <a href=
"../vttest/vttest.html">vttest</a>. Beginning with late 1999,
reports indicate that it does not properly parse ANSI control
sequences: the vim editor is using xterm's vt220-style "Send
Device Attributes" (Secondary DA) control sequence to obtain the
terminal emulator's version. That is, it sends</p>
<blockquote>
<pre>
\E[>c
</pre>
</blockquote>
<p>expecting a response such as</p>
<blockquote>
<pre>
\E[>0;138;0c
</pre>
</blockquote>
<p>for vt100. The bug report indicates that the "c" sent by vim
is echoed rather than interpreted by the emulator.</p>
<p>But it suffices for vi.</p>
<p>A more recent GNOME Terminal uses the VTE widget. I observed
version 1.4.0.4 in late 2001, which mentioned it in the credits
(although VTE 0.1's ChangeLog mentions no date before February
2002). It does not implement a complete vt102: it was missing
several features which can be demonstrated in <a href=
"../vttest/vttest.html">vttest</a>). Most of the bugs in the
Device Attributes responses remain, but it works a little better
with vim. However, there are problems with the alternate screen
that show up with vim. Again, these can be demonstrated with
vttest (menu 11.6.3 in the 20011130 snapshot).</p>
<p>Rather than evolving from zvt, VTE is largely a new work. It
does credit zvt in one place. However, its source code uses
xterm's source code as a resource, accounting for odd (often
incomplete) chunks. Reviewing 0.9.0 (September 2002):</p>
<ul>
<li>the termcap file. The last comment in the file is copied
from xterm's source. The content of course is generated from
ncurses with a small number of changes.</li>
<li>the parser <code>src/vte.c</code> —a 14,125 line
file. For example, the chunks related to DEC VT220 keyboard
queries and DEC private modes contain comments copied from
xterm's source code.</li>
</ul>
<p>Later versions of VTE incorporate more features (and comments,
symbol names, etc), from xterm's source. In some instances, the
copied features were disabled by Red Hat's package for xterm.
<a href=
"https://bugzilla.redhat.com/show_bug.cgi?id=122815">Here</a> is
a related bug report, for key bindings.</p>
<p>The documentation for GNOME terminal asserts:</p>
<blockquote>
<p>GNOME Terminal emulates the xterm application developed by
the X Consortium. In turn, the xterm application emulates the
DEC VT102 terminal and also supports the DEC VT220 escape
sequences. An escape sequence is a series of characters that
starts with the Esc character. GNOME Terminal accepts all of
the escape sequences that the VT102 and VT220 terminals use for
functions such as to position the cursor and to clear the
screen.</p>
</blockquote>
<p>That sounds fine, except that it is both inaccurate and
misleading:</p>
<dl>
<dt>inaccurate</dt>
<dd>
combining the "X Consortium" and "DEC VT220", for example,
since that was done after the demise of said organization.
<p>It emulates a <em>subset</em> of VT100, lacks support for
most of the VT220 control sequences (including some used for
positioning the cursor) that are not recognized by a
VT100.</p>
<p>Even in the subset which it emulates, GNOME Terminal has
bugs. Many of these are easy to demonstrate with vttest.</p>
</dd>
<dt>misleading</dt>
<dd>as noted in <a href="xterm.faq.html#ctlseqs_ms">Xterm
Control Sequences</a>, xterm (mostly after "X Consortium")
supports control sequences which are not VT100/VT220. GNOME
Terminal implements many of these, but not all.</dd>
</dl>
<p>Perhaps that was unintentional – GNOME developers did
not appear to document what their program <em>does</em> outside
of that remark. However, an inspection of the changelog for
libvte (VTE) does show that most of the borrowing from xterm is
cited in an oblique manner – not once mentioning XFree86
for example, leaving the impression (as indicated by "X
Consortium") that all of the work on xterm was done before
development of GNOME Terminal commenced.</p>
<p>Most of this observation was documented between 2000 and 2007.
Other than maintenance, development of GNOME Terminal appears to
have paused in 2005. As of 2009, its maintainer is (of the
development team), the least knowledgeable about terminal
emulation. So there is no progress on the large number of bug
reports related to xterm-compatibility.</p>
<h3 id="vte_widget-id"><a name="vte_widget" id="vte_widget">Notes
on VTE</a></h3>
<p>VTE's README file asserts</p>
<blockquote>
<p>VTE supports Unicode and character set conversion, as well
as emulating any terminal known to the system's terminfo
database.</p>
</blockquote>
<p>The latter part of that ("emulating any terminal") is
incorrect. It does have the ability to work with the standard
function-key definitions which can be defined in a terminfo
description.</p>
<p>Some of the function-key logic is adapted from xterm;
generally refactoring the xterm source-code to make it appear
different. In places however (naming conventions and comments),
there is some verbatim copying. The same comment is true of
"character set conversion". None of that is reflected in VTE's
changelog.</p>
<p>As an aside, the credits in GNOME Terminal's "About" box also
are inaccurate. For several years (according to its change-log),
most of the work on VTE (the principal part of the program) was
done by Nalin Dahyabhai.</p>
<p>xterm on the other hand, can be told with the
<code>tcapFunctionKeys</code> resource setting to use a more
complete subset, based on the ncurses extended terminal
descriptions. Even xterm's terminfo/termcap descriptions do not
cover the (literally) thousands of keyboard combinations which
are available via its resource settings.</p>
<p>Outside of function-keys, VTE provides no ability to emulate
"any terminal". A casual glance at its source code reveals the
following:</p>
<ul>
<li>no support for VT220-style protected areas.</li>
<li>inconsistent support for modifier keys (the subject of
several bug reports misdirected toward ncurses).</li>
<li>only a subset of the standard terminfo/termcap properties
is used (5/36 booleans, 3/33 numbers, 125/242 strings other
than function-keys).</li>
<li>a pervasive assumption that the terminal is something like
xterm, e.g., to provide hardcoded behavior where termcap might
describe something different.</li>
<li>it uses termcap to retrieve data, rather than providing a
choice between terminfo/termcap, opening up the problem of
using an obsolete database.</li>
<li>using termcap also means that it has no guidance for
following features which are absent or have
limited-functionality compared to terminfo, such as setting
video attributes, colors, etc.</li>
</ul>
<p>For instance, VTE cannot emulate <a href=
"xterm.faq.html#bug_dtterm">dtterm</a>, because of differences in
color behavior. In fact, VTE does not use any of the termcap data
to support its interpretation of color control sequences.</p>
<p>Because of GNOME Terminal's reputation for excessive code
bloat, developers of every other program based on VTE advertise
their version as reduced memory usage, faster startup, etc. Here
are a few of the available ones:</p>
<h4 id="bug_osso_xterm-id"><a name="bug_osso_xterm" id=
"bug_osso_xterm">osso-xterm</a> <a href=
"https://garage.maemo.org/projects/osso-xterm/">link</a></h4>
<p>This is one of several GUI "skins" over the VTE widget which
forms the functional core of GNOME Terminal.</p>
<p>Its home page refers to "at least two versions". I recall
seeing an older version which was apparently not based on VTE.
There does not appear to be any current page (as of 2009) for
that version.</p>
<h4 id="bug_roxterm-id"><a name="bug_roxterm" id=
"bug_roxterm">roxterm</a> <a href=
"http://roxterm.sourceforge.net/">link</a></h4>
<p>This is one of several GUI "skins" over the VTE widget which
forms the functional core of GNOME Terminal.</p>
<h4 id="bug_xfce_term-id"><a name="bug_xfce_term" id=
"bug_xfce_term">XFCE Terminal</a> <a href=
"http://terminal.os-cillation.com/">link</a></h4>
<p>This is one of several GUI "skins" over the VTE widget which
forms the functional core of GNOME Terminal.</p>
<h3 id="bug_multignome-id"><a name="bug_multignome" id=
"bug_multignome">MULTI GNOME TERMINAL (MGT)</a> <a href=
"http://multignometerm.sourceforge.net/">link</a></h3>
<p>Of particular note, MGT 1.4.0 announcement claims that it
works properly for all of <a href=
"../vttest/vttest.html">vttest</a>)'s tests. On the positive
side, it does do VT52 emulation, but (reading the source code did
not help) it apparently does not really do VT220 from vttest's
perspective.</p>
<h3 id="bug_hanterm-id"><a name="bug_hanterm" id=
"bug_hanterm">HANTERM</a> <a href=
"http://www.debian.org/Packages/frozen/x11/hanterm.html">download</a></h3>
<p>HanTerm stands for "Hangul term" (Korean). This is based on
the XFree86 source.</p>
<h3 id="bug_konsole-id"><a name="bug_konsole" id=
"bug_konsole">KONSOLE</a> <a href=
"http://www.kde.org/">link</a></h3>
<p>More than just a rewrite of <a href=
"xterm.faq.html#bug_kvt">kvt</a> into C++. But there are several
incompatibilities between konsole (noted with version 1.0.2 in
late 2001) and xterm:</p>
<ul>
<li>none of the selections of keyboard mappings match the
actual behavior of xterm (a few come close, but do so by
matching the terminfo descriptions rather than the programs).
In particular, the application keypad does not send vt100-style
escapes.</li>
<li><a href="../vttest/vttest.html">vttest</a>) demonstrates
that konsole does not properly ignore escape sequences to
switch character sets that it does not support. Also, the
developers of konsole did use an old version of vttest, but
that was to add a bogus Device Attributes response (claimed to
be for "vt220", but not corresponding to any that DEC
produced). They do not use the newer version of vttest (which
was available more than a year before development of konsole
began).</li>
<li>konsole implements several features from XFree86 xterm, but
some are done incorrectly. In particular, the <a href=
"xterm.faq.html#xterm_tite">private setmode 1049</a> does not
save and restore the cursor, causing the cursor to be in
unexpected locations after exiting a fullscreen application
such as vi.</li>
</ul>
<p>The problems with setmode 1049 were fixed after some time;
other issues linger on.</p>
<p>Like <a href="xterm.faq.html#bug_gnometerm">GNOME
Terminal</a>, konsole's documentation is incomplete and
inaccurate. This gem from its handbook illustrates the
problem:</p>
<blockquote>
<p>After a decade, Konsole is the first rewrite from the ground
up. While xterm has definitely been hacked to death (its README
begins with the words Abandon All Hope, Ye Who Enter Here),
Konsole offers a fresh start using contemporary technologies
and understanding of X.</p>
</blockquote>
<p>The problem:</p>
<ul>
<li>the remark was apparently written in 1997. It was
inaccurate at that time, since it disregards the earlier
xvt/rxvt applications. Limiting it only to a plain statement
that konsole was a rewrite of <a href=
"xterm.faq.html#bug_kvt">kvt</a> would have been more accurate.
Lacking that context, we find nonfactual articles such as
<a href="http://everything2.com/index.pl?node=Konsole">this</a>
on the net.</li>
<li>for those lacking a proper education, the README was
apparently intended to be a humorous reference to Dante's
<em>Inferno</em>.</li>
<li>reading konsole's source code and considering "hacked to
death" can provide some occasion for humor. Enjoy.</li>
</ul>
<h3 id="bug_kterm-id"><a name="bug_kterm" id=
"bug_kterm">KTERM</a> <a href=
"ftp://ftp.x.org/contrib/applications/kterm-6.2.0.tar.gz">download</a></h3>
<p>KTerm stands for "Kanji term" (Japanese). This is based on the
X Consortium source, with the same bugs (though the list of
original authors has been removed; the modifications that
comprise kterm is relatively small).</p>
<ul>
<li>implements non-bce color model</li>
<li>implements status line, but uses non-DEC escape sequences
for this.</li>
</ul>
<p>There is a variation of xvt (ancestor of rxvt) originally
known as <a name="bug_kvt" id="bug_kvt">kvt</a> bundled with
<a href="http://www.kde.org/">KDE</a> which may be referred to as
"kterm", but I do not find it interesting, other than to comment
that it was a poor choice of name.</p>
<h3 id="bug_mlterm-id"><a name="bug_mlterm" href=
"http://mlterm.sourceforge.net/" id="bug_mlterm">MLTERM</a></h3>
<p>Mlterm is not based on xterm or rxvt source, though it
implements many of their features. It does fairly well with
<a href="../vttest/vttest.html">vttest</a>, except for some odd
misbehavior in operations that save/restore the cursor
position.</p>
<h3 id="bug_mterm-id"><a name="bug_mterm" id=
"bug_mterm">MTERM</a></h3>
<p>There are a few variants of this: the xterm bundled with some
Motif clients is more common. More interesting, however is one
(not Motif), attributed to "Der Mouse".</p>
<blockquote>
<pre>
(mouse@Lightning.McRCIM.McGill.EDU) Available:
larry.mcrcim.mcgill.edu (132.206.1.1) in
/X/mterm.src/mterm.ball-o-wax.
</pre>
</blockquote>
<p>I saw only an incomplete version of this while it was
advertised in the mid-90's. It is available by email from
<mouse@Rodents.Montreal.QC.CA>. or via <a href=
"ftp://ftp.rodents.montreal.qc.ca/mouse/X/mterm.src/">ftp</a>.
This is not a patched version of xterm, though it was apparently
written, like rxvt, to emulate vt100's. While it does have some
interesting features (such as blinking characters), overall it
does not do as well with <a href=
"../vttest/vttest.html">vttest</a> as the more widely known
emulators.</p>
<h3 id="bug_mxterm-id"><a name="bug_mxterm" id=
"bug_mxterm">MXTERM</a></h3>
<p>There are several variants on this: xterm adapted for Motif
libraries. I have seen none that work properly:</p>
<ul>
<li><a href=
"http://www.cmbi.kun.nl/~schaft/mxterm/mxterm.html">MXTERM: a
motif Xterm with character attributes color rendered</a> I've
noticed this one only recently. It is a reworking of the
earlier patches for color_xterm (credited to Erik Fortune at
SGI) and the Motif widgets (apparently first done by Ivan M.
Hajadi at SGI in 1991, but credited in this release to Mahesh
Neelakanta, for Motif 1.2.4).</li>
<li>
<a href=
"http://www.muquit.com/muquit/software/ansi_xterm/ansi_xterm.html">
ANSI Xterm with Motif Scrollbar</a> Usually seen as the
ansi-xterm-R6-motif-sb patch, I used this as the starting
point for changes to my #82 patch of xterm in August 1998.
<p>The original patch changes only the scrollbars to Motif,
leaving the popup menus in Athena widgets. That was not what
I wanted. My motivation for using Motif is not for
performance or esthetics, of course, but to make it simpler
to build on hosts that have no Athena widgets installed.</p>
<p>I set those changes aside, having found (the hard way)
that the Motif library has hardcoded behavior regarding the
control right-mouse button. According to the O'Reilly book on
Motif programming (volume 6), it does a server grab when
processing menus. Making the menus behave just as in the
Athena widgets can cause the X server to hang. (I was able to
do this with both Lesstif and Motif libraries). Given that, I
decided to restructure the menus entirely, making a toolbar
which could support at compile-time either widget set.</p>
</li>
<li><a href=
"http://web.archive.org/web/*/http%3A//www.fh-wilhelmshaven.de/~akcaagaa/index_mxterm.html">
mxterm</a> This is a different reworking of the Motif widget
patch, using a 1993 version (ignoring the more recent 1994
patches noted above). However, it appears to have the same
technical defect that I noted above.</li>
</ul>
<h3 id="bug_nxterm-id"><a name="bug_nxterm" id=
"bug_nxterm">NXTERM</a></h3>
<p>Distributed with Redhat Linux 5.2, it is a repackaging of
<a href="xterm.faq.html#bug_ansi_xterm">xterm-sb_right-ansi</a>,
to use the Xaw3d widget set. This is based on the X Consortium
X11R6 source, with the same bugs.</p>
<ul>
<li>implements non-bce color model</li>
<li>does not implement SGR 39 and SGR 49, all attributes are
reset when changing colors.</li>
<li>popup menus do not appear to work.</li>
</ul>
<p>Starting with Redhat 6.0, <em>nxterm</em> is the XFree86 3.3.6
xterm. Unfortunately Redhat neglected to update their termcap for
nxterm to match the program.</p>
<h3 id="bug_rxvt-id"><a name="bug_rxvt" id="bug_rxvt">RXVT</a>
<a href="http://www.rxvt.org/">link</a></h3>
<p>Rxvt's manual page states the following unqualified
comment:</p>
<blockquote>
<p>rxvt, version 2.6.2, is a colour vt102 terminal emulator
intended as an xterm(1) replacement for users who do not
require features such as Tektronix 4014 emulation and
toolkit-style configurability. As a result, rxvt uses much less
swap space -- a significant advantage on a machine serving many
X sessions.</p>
</blockquote>
<p>How much is <em>much less</em>? Perhaps not as much as one
would think from reading that. The Tektronix emulation in xterm
(which has been optional since late 1997) accounts for about 25kb
of the code.</p>
<p>The toolkit-style configurability glibly referenced is the
ability to redefine keys on the keyboard without recompiling the
program, i.e., the <a href=
"xterm.faq.html#how2_fkeys">translations</a> resource. It also is
the way mouse events and other actions are passed to xterm.</p>
<p>The toolkit-style configurability accounts for about 300kb,
which does add up if you happen to be running 50 xterm processes
(i.e., about 10Mb).</p>
<p>This comment was topical in December 2001:</p>
<blockquote>
<p>Compared with something like GNOME Terminal, which takes 2-3
times, or KDE konsole, which takes 15-20 times as much memory
to run, xterm and rxvt memory requirements are
indistinguishable to the normal user.</p>
</blockquote>
<p>In June 2010, the numbers have changed somewhat. Here is a
table showing the total application and library sizes needed for
each of the terminal emulators on my development machine. All
sizes are in kb (1024 bytes).</p>
<table border="1" summary="Comparing XTerm's size">
<tr>
<th>program</th>
<th>base size</th>
<th>total size</th>
<th>libraries</th>
</tr>
<tr>
<td>aterm</td>
<td>127</td>
<td>10763</td>
<td>45</td>
</tr>
<tr>
<td>color_xterm</td>
<td>142</td>
<td>3647</td>
<td>13</td>
</tr>
<tr>
<td>Eterm</td>
<td>1</td>
<td>5126</td>
<td>19</td>
</tr>
<tr>
<td>fbiterm</td>
<td>6</td>
<td>2424</td>
<td>8</td>
</tr>
<tr>
<td>gnome-terminal</td>
<td>292</td>
<td>14587</td>
<td>51</td>
</tr>
<tr>
<td>hpterm</td>
<td>146</td>
<td>14386</td>
<td>31</td>
</tr>
<tr>
<td>konsole</td>
<td>2</td>
<td>39815</td>
<td>71</td>
</tr>
<tr>
<td>kterm</td>
<td>226</td>
<td>4194</td>
<td>17</td>
</tr>
<tr>
<td>mlterm</td>
<td>316</td>
<td>6606</td>
<td>27</td>
</tr>
<tr>
<td>mrxvt</td>
<td>298</td>
<td>4515</td>
<td>19</td>
</tr>
<tr>
<td>multi-aterm</td>
<td>144</td>
<td>2821</td>
<td>7</td>
</tr>
<tr>
<td>pterm</td>
<td>405</td>
<td>12817</td>
<td>42</td>
</tr>
<tr>
<td>rxvt 2.6.4</td>
<td>108</td>
<td>2725</td>
<td>6</td>
</tr>
<tr>
<td>rxvt 2.7.10</td>
<td>152</td>
<td>2829</td>
<td>7</td>
</tr>
<tr>
<td>rxvt-unicode</td>
<td>1259</td>
<td>13641</td>
<td>49</td>
</tr>
<tr>
<td>terminal.app</td>
<td>211</td>
<td>15274</td>
<td>29</td>
</tr>
<tr>
<td>wterm</td>
<td>110</td>
<td>2922</td>
<td>11</td>
</tr>
<tr>
<td>xfce4-terminal</td>
<td>148</td>
<td>14059</td>
<td>48</td>
</tr>
<tr>
<td>xgterm</td>
<td>953</td>
<td>4602</td>
<td>14</td>
</tr>
<tr>
<td>xhpterm</td>
<td>130</td>
<td>2748</td>
<td>6</td>
</tr>
<tr>
<td>xiterm</td>
<td>12</td>
<td>3762</td>
<td>16</td>
</tr>
<tr>
<td>xterm (everything)</td>
<td>346</td>
<td>5484</td>
<td>24</td>
</tr>
<tr>
<td>xterm (minimal)</td>
<td>186</td>
<td>4123</td>
<td>15</td>
</tr>
<tr>
<td>xterm-r5</td>
<td>135</td>
<td>4164</td>
<td>11</td>
</tr>
<tr>
<td>xterm-r6</td>
<td>140</td>
<td>4169</td>
<td>11</td>
</tr>
</table>
<p>Counting the libraries is appropriate, since some programs
such as xiterm and the VTE-based programs are implemented in
libraries.</p>
<p>These comments apply to versions of <em>rxvt</em> through
2.21:</p>
<ul>
<li>clearing the screen resets colors</li>
<li>does not have a delete key</li>
<li>the implementation of <code>ech</code> (erase characters)
does not follow DEC VT220 (also ISO 6429), causing applications
using this function to misbehave.</li>
</ul>
<p>A newer version (upgraded to an beta as of 2.6.PRE3, however,
since it no longer dumps core in <a href=
"../vttest/vttest.html">vttest</a>) is reported to fix the
<code>ech</code> bug. However, it is less VT100-compatible than
the earlier versions such as 2.21b because it does not render
reverse video (<code>DECSCNM</code>) properly. All versions do
not update the screen frequently enough, making animation
ineffective. See <a href="../vttest/vttest.html">vttest</a>,
tests 1 and 2.</p>
<p>One longstanding issue with rxvt impacts use of xterm. While
rxvt does not use the X Toolkit (and corresponding X resource
matching), it does read your <code>.Xdefaults</code> and
app-defaults files to extract resource settings. That in itself
would not be a problem. However, since rxvt also looks for
resources in the <code>XTerm</code> class (a parasitic
relationship like setting $TERM to "xterm" based on the
presumption that it is a nuisance to install its configuration
files), there have been several occasions on which xterm's
app-defaults files have been modified to accommodate rxvt's
variant usage.</p>
<p>That comment applies mainly to the resource
<strong>patterns</strong>. However, even when the pattern is
reasonably unambiguous, but overbroad, the results can be
conflicting. For example, some versions of rxvt may accept a
<code>font</code> resource which does not match the XLFD pattern.
It accepts a prefix of "xft:". This feature (apparently
introduced by <a href="xterm.faq.html#bug_konsole">konsole</a>)
tells rxvt to interpret the remainder of the string as a TrueType
(Xft) font rather than a bitmap font. xterm uses the
<code>faceName</code> resource for these values.</p>
<h3 id="bug_st">st <a href="http://st.suckless.org">link</a></h3>
<p>Rxvt revisited, this program depends only on the X11 library.
As of January 2013, it is in heavy development, and (according to
comments on its developer's list) growing steadily as the
developers implement useful features adapted from xterm.</p>
<p>For instance, the size counting libraries for st 0.3 on my
Debian testing machine is on a par with rxvt (and half that of
xterm, which uses the X Toolkit library).</p>
<p>By the way, the page quotes the README file from xterm's
sources, omitting my editorial comment at the top noting that the
paraphrase of the opening from Dante's <em>Inferno</em> dated
from 1991, and pointing to this FAQ to provide better
context.</p>
<h3 id="bug_xgterm-id"><a name="bug_xgterm" id=
"bug_xgterm">XGTERM</a> <a href=
"ftp://iraf.noao.edu/iraf/x11iraf/">link</a></h3>
<p>It has some features which are also in color_xterm:(non-bce
ANSI color, colorBD and colorUL resources, cursor warping, etc.
The main feature is its Tektronix graphics emulation, which is
the main reason for this particular program. Neither program has
a change-log, so it is not easy to say which influenced the
other.</p>
<p>That is from reading the source code. However testing under
Debian Linux, something is wrong with the resource processing
(neither popup menus nor colors work).</p>
<h3 id="bug_xiterm-id"><a name="bug_xiterm" id=
"bug_xiterm">XITERM</a> <a href=
"ftp://metalab.unc.edu/pub/Linux/X11/terms/">link</a></h3>
<p>This appears to be rxvt 2.20, lightly reformatted, with a few
ifdef's changed.</p>
<p>That is, it was. The name was later appropriated by a
different <a href=
"http://web.archive.org/web/*/http%3A//oss.software.ibm.com/linux/projects/iterm/">
program</a>, which also uses the name <code>iterm</code>. Like
gnome-terminal, iterm aims to be an xterm-emulator rather than a
VT102- or VT220-emulator.</p>
<p>An earlier <a href=
"http://web.archive.org/web/*/http%3A//www.openi18n.org">attempt</a>
by the same author (the "CSI-xterm") incorporates some of the
changes I made for XFree86 xterm via cut and paste (but does not
mention this in its README). It is said to be the basis for
Solaris 10 xterm.</p>
<p>Both have similar problems running <a href=
"../vttest/vttest.html">vttest</a>.</p>
<h2 id="building_it-id"><a name="building_it" id=
"building_it">How do I build <strong>XTerm</strong>?</a></h2>
<p>Building a copy of xterm is simple, provided that you have a
development configuration for X11:</p>
<ul>
<li>Header files and libraries. If you do not have the header
files (usually under /usr/include/X11) for your system, you are
better off building the libraries yourself. Xterm can be built
with either X11R5 or X11R6 libraries; however X11R6 requires
much more data to be installed before xterm will run. Xterm
uses the <code>Xaw</code> library for popup menus.</li>
<li>imake and <code>xmkmf</code>. These utilities produce a
Makefile from the Imakefile. They are not essential, but
useful, particularly on systems with unusual
configurations.</li>
</ul>
<p>If you have a working <code>xmkmf</code> script (or correctly
configured imake utility), all you need to do is type</p>
<blockquote>
<pre>
xmkmf
make
</pre>
</blockquote>
<p>I have written a <em>configure</em> script for xterm which can
use <code>imake</code> (or <code>xmkmf</code>) to generate a
Makefile from the Makefile.in. Or it can do without
<code>imake</code> entirely. I have restructured xterm to
eliminate most hardcoded <code>#ifdef</code>'s, replacing them
with definitions that can be derived with the configuration
script. The <em>configure</em> script is more flexible than
<em>xmkmf</em>, since it allows you to enable or disable a
variety of features. Type</p>
<blockquote>
<pre>
configure --help
</pre>
</blockquote>
<p>to get a list of options.</p>
<p>Though I have replaced most hardcoded ifdef's with
autoconfigured values, it will still continue to build properly
with the imake environment.</p>
<p>However, I usually build xterm using the configure script. By
default, it looks for imake and will use it to help with a few
places where a reliable configure check cannot be created. One of
these (see <a href="xterm.faq.html#narrowproto">Why doesn't the
scrollbar work?</a>) can be a problem.</p>
<p>As with all of my projects, I routinely check for strict
compiler warnings. For gcc, that is done with the "gcc-stricter"
script which you can find <a href=
"../scripts/readme.html">here</a>. The X libraries have a
longstanding issue which has been ignored so far (as of
mid-2012). To work around this (and get useful warnings), I apply
this patch:</p>
<blockquote>
<pre>
--- Intrinsic.h.orig 2009-08-25 13:22:15.000000000 -0400
+++ Intrinsic.h 2009-12-06 09:48:39.000000000 -0500
@@ -66,7 +66,11 @@
#define XtSpecificationRelease 6
+#ifdef _CONST_X_STRING
+typedef const char *String;
+#else
typedef char *String;
+#endif
/* We do this in order to get "const" declarations to work right. We
* use _XtString instead of String so that C++ applications can
--- Xresource.h.orig 2009-07-19 14:43:21.000000000 -0400
+++ Xresource.h 2009-12-06 10:11:19.000000000 -0500
@@ -338,8 +338,8 @@
} XrmOptionKind;
typedef struct {
- char *option; /* Option abbreviation in argv */
- char *specifier; /* Resource specifier */
+ _Xconst char *option; /* Option abbreviation in argv */
+ _Xconst char *specifier; /* Resource specifier */
XrmOptionKind argKind; /* Which style of option it is */
XPointer value; /* Value to provide if XrmoptionNoArg */
} XrmOptionDescRec, *XrmOptionDescList;
</pre>
</blockquote>
<p>I made note of it on the Xorg <a href=
"http://lists.x.org/archives/xorg-devel/2010-May/009052.html">mailing
list</a>, but as you can see, there was no response.</p>
<h2 id="report_bugs-id"><a name="report_bugs" id=
"report_bugs">How do I report bugs?</a></h2>
<p>You should report bugs to <a href=
"mailto:dickey@invisible-island.net">me</a>. I also respond to
bug reports in a number of bug-tracking systems, though some are
less open to searches than others. See also <a href=
"../scripts/readme.html">Analyzing problems with configure
scripts</a></p>
<h2 id="more_info-id"><a name="more_info" id=
"more_info">Additional Information</a></h2>
<p>There appears to be no comprehensive source of information on
xterm better than the documentation which comes with the source
code</p>
<ul>
<li><a href="xterm.log.html">XTerm change log</a></li>
<li><a href="xterm.faq.html#xterm_man">The XTerm
Manual</a></li>
<li><a href="xterm.faq.html#ctlseqs_ms">XTerm Control
Sequences</a></li>
<li><a href="xterm.faq.html#resize_man">resize</a> – set
TERMCAP and terminal settings to current xterm window size</li>
<li><a href="xterm.faq.html#uxterm_man">uxterm</a> – a
UTF-8 wrapper for XTerm</li>
<li><a href="xterm.faq.html#koi8rxterm_man">koi8rxterm</a>
– a KOI8-R wrapper for XTerm</li>
<li><a href="xterm.faq.html#luit_prog">luit</a> – Locale
and ISO 2022 support for Unicode terminals</li>
<li><a href="xterm.faq.html#other_sites">Other Sites</a></li>
</ul>
<h3 id="other_sites-id"><a name="other_sites" id=
"other_sites">Other Sites</a></h3>
<ul>
<li>I have found Richard Shuford's archive to be invaluable for
notes on the DEC VT220 and related terminals. This was a
<a href=
"http://web.eecs.utk.edu/~shuford/terminal_index.html">webpage</a>
but was last seen via <a href=
"ftp://cs.utk.edu/pub/shuford/">ftp</a>. (I have a snapshot
from the ftp site).</li>
<li>Though not available at the time that I was collecting most
of my notes, <a href="http://vt100.net">VT100.net</a> is also a
good source of primary information.</li>
</ul>
<h3 id="xterm_man-id"><a name="xterm_man" id="xterm_man">The
XTerm Manual</a></h3>
<p>The command-line options, X resources and similar configurable
options of xterm are documented in the manual page.</p>
<p>Here are copies of the file in various forms: <a href=
"manpage/xterm.html">html</a>, <a href=
"manpage/xterm.pdf">pdf</a>, <a href="manpage/xterm.ps">ps</a>
and <a href="manpage/xterm.txt">text</a>.</p>
<h3 id="ctlseqs_ms-id"><a name="ctlseqs_ms" id="ctlseqs_ms">Xterm
Control Sequences</a></h3>
<p>Control sequences, i.e., programming information are in the
<code>ctlseqs.ms</code> file which I bundle with the <a href=
"xterm.faq.html#latest_version">program source</a>. (It used to
be in the same directory in the X distribution, but was moved to
a different part of the tree long ago). Note that you must format
this file with different options than a manpage, e.g.,</p>
<blockquote>
<pre>
tbl ctlseqs.ms | nroff -ms >ctlseqs.txt
tbl ctlseqs.ms | groff -ms >ctlseqs.ps
</pre>
</blockquote>
<p>As a PostScript or PDF file, the individual letters of the
control sequences are all boxed, for emphasis, but I find the
text file equally readable.</p>
<p>Here are copies of the file in various forms: <a href=
"ctlseqs/ctlseqs.html">html</a>, <a href=
"ctlseqs/ctlseqs.pdf">pdf</a>, <a href=
"ctlseqs/ctlseqs.ps">ps</a> and <a href=
"ctlseqs/ctlseqs.txt">text</a>.</p>
<h3 id="resize_man-id"><a name="resize_man" id=
"resize_man">resize – set TERMCAP and terminal settings to
current xterm window size</a></h3>
<p><em>resize</em> is useful by itself, but is maintained for
historical reasons as part of xterm. <a href=
"manpage/resize.html">html</a>, <a href=
"manpage/resize.pdf">pdf</a>, <a href="manpage/resize.ps">ps</a>
and <a href="manpage/resize.txt">text</a>.</p>
<h3 id="uxterm_man-id"><a name="uxterm_man" id=
"uxterm_man">uxterm – a UTF-8 wrapper for xterm</a></h3>
<p>XTerm does not automatically <em>set</em> your locale. It can
be told to <em>use</em> your locale settings. This is a shell
script which sets xterm's resources to use UTF-8 encoding, and
use UTF-8 fonts. There is a similar <em>lxterm</em> script, but
it relies upon non-portable applications, unlike uxterm.</p>
<p>Here are copies of uxterm's documentation: <a href=
"manpage/uxterm.html">html</a>, <a href=
"manpage/uxterm.pdf">pdf</a>, <a href="manpage/uxterm.ps">ps</a>
and <a href="manpage/uxterm.txt">text</a>.</p>
<p>Incidentally, there was a different program named "uxterm"
before the shell script was added to xterm in <a href=
"xterm.log.html#xterm_137">mid-2000</a>. <a href=
"http://czyborra.com/unicode/terminals.html">Roman Czyborra
commented</a> in 1998 that it was based on the original X11 xterm
source (very likely, since "strings" run on the executable shows
the xterm actions, resources and even the Tek4014 support). There
are few references to it to provide details: the first appearance
was in <a href=
"http://www.unicode.org/mail-arch/unicode-ml/Archives-Old/UML001/0042.html">
1994</a>, and the last was Czyborra's page in 1998. For the
curious, there is a copy on <a href=
"http://www.ibiblio.org/pub/packages/ccic/software/x-win/uxterm/uxterm.README">
ibiblio.org</a> (no Linux executables, no source, however).</p>
<h3 id="koi8rxterm_man-id"><a name="koi8rxterm_man" id=
"koi8rxterm_man">koi8rxterm – a KOI8-R wrapper for
xterm</a></h3>
<p>As a special case, this wrapper is packaged with xterm to
provide KOI8-R encoding.</p>
<p>Here are copies of koi8rxterm's documentation: <a href=
"manpage/koi8rxterm.html">html</a>, <a href=
"manpage/koi8rxterm.pdf">pdf</a>, <a href=
"manpage/koi8rxterm.ps">ps</a> and <a href=
"manpage/koi8rxterm.txt">text</a>.</p>
<h3 id="luit_prog-id"><a name="luit_prog" id="luit_prog">luit
– Locale and ISO 2022 support for Unicode
terminals</a></h3>
<p><a href="../luit/luit.html">luit</a> also is maintained as
part of xterm, since its upstream maintainer is inactive, and the
ostensible maintainers have more than once delivered unusable
versions, causing many bug reports to be issued against
xterm.</p>
<h2 id="future_work-id"><a name="future_work" id=
"future_work">Ongoing/future work</a></h2>
<ul>
<li>soft (downloadable) fonts</li>
<li>printer interface
<p>Done, except for the corresponding support in the VT52
emulation. It would be nice to have a dialog to control
this.</p>
</li>
<li>allow alternate libraries for popup-menus and dialogs
<p>My configure script currently provides tests for the
variations of Athena widgets (Xaw3D, neXtaw). I intend to
make additional changes to support <a href=
"xterm.faq.html#bug_mxterm">Motif scrollbars and menus</a>.
Motif requires a different style of interface for the menus:
binding a popup menu to control right mouse may cause the
server to hang. As an intermediate step, I implemented a
toolbar for the Athena widgets. In turn, that works well
enough except with XFree86 4.x: the Xaw library geometry
management is broken. (Other implementations of the Athena
widgets work well enough).</p>
</li>
<li>popup window that shows hex code for content of a character
cell and hexadecimal keyboard entry for all Unicode characters
(ISO 14755)</li>
<li>correct cut&paste of TAB character</li>
</ul>
</body>
</html>
|