This file is indexed.

/usr/share/perl/5.22.1/pod/perlebcdic.pod is in perl-doc 5.22.1-9ubuntu0.6.

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
=encoding utf8

=head1 NAME

perlebcdic - Considerations for running Perl on EBCDIC platforms

=head1 DESCRIPTION

An exploration of some of the issues facing Perl programmers
on EBCDIC based computers.

Portions of this document that are still incomplete are marked with XXX.

Early Perl versions worked on some EBCDIC machines, but the last known
version that ran on EBCDIC was v5.8.7, until v5.22, when the Perl core
again works on z/OS.  Theoretically, it could work on OS/400 or Siemens'
BS2000  (or their successors), but this is untested.  In v5.22, not all
the modules found on CPAN but shipped with core Perl work on z/OS.

If you want to use Perl on a non-z/OS EBCDIC machine, please let us know
by sending mail to perlbug@perl.org

Writing Perl on an EBCDIC platform is really no different than writing
on an L</ASCII> one, but with different underlying numbers, as we'll see
shortly.  You'll have to know something about those L</ASCII> platforms
because the documentation is biased and will frequently use example
numbers that don't apply to EBCDIC.  There are also very few CPAN
modules that are written for EBCDIC and which don't work on ASCII;
instead the vast majority of CPAN modules are written for ASCII, and
some may happen to work on EBCDIC, while a few have been designed to
portably work on both.

If your code just uses the 52 letters A-Z and a-z, plus SPACE, the
digits 0-9, and the punctuation characters that Perl uses, plus a few
controls that are denoted by escape sequences like C<\n> and C<\t>, then
there's nothing special about using Perl, and your code may very well
work on an ASCII machine without change.

But if you write code that uses C<\005> to mean a TAB or C<\xC1> to mean
an "A", or C<\xDF> to mean a "E<yuml>" (small C<"y"> with a diaeresis),
then your code may well work on your EBCDIC platform, but not on an
ASCII one.  That's fine to do if no one will ever want to run your code
on an ASCII platform; but the bias in this document will be in writing
code portable between EBCDIC and ASCII systems.  Again, if every
character you care about is easily enterable from your keyboard, you
don't have to know anything about ASCII, but many keyboards don't easily
allow you to directly enter, say, the character C<\xDF>, so you have to
specify it indirectly, such as by using the C<"\xDF"> escape sequence.
In those cases it's easiest to know something about the ASCII/Unicode
character sets.  If you know that the small "E<yuml>" is C<U+00FF>, then
you can instead specify it as C<"\N{U+FF}">, and have the computer
automatically translate it to C<\xDF> on your platform, and leave it as
C<\xFF> on ASCII ones.  Or you could specify it by name, C<\N{LATIN
SMALL LETTER Y WITH DIAERESIS> and not have to know the  numbers.
Either way works, but require familiarity with Unicode.

=head1 COMMON CHARACTER CODE SETS

=head2 ASCII

The American Standard Code for Information Interchange (ASCII or
US-ASCII) is a set of
integers running from 0 to 127 (decimal) that have standardized
interpretations by the computers which use ASCII.  For example, 65 means
the letter "A".
The range 0..127 can be covered by setting the bits in a 7-bit binary
digit, hence the set is sometimes referred to as "7-bit ASCII".
ASCII was described by the American National Standards Institute
document ANSI X3.4-1986.  It was also described by ISO 646:1991
(with localization for currency symbols).  The full ASCII set is
given in the table L<below|/recipe 3> as the first 128 elements.
Languages that
can be written adequately with the characters in ASCII include
English, Hawaiian, Indonesian, Swahili and some Native American
languages.

Most non-EBCDIC character sets are supersets of ASCII.  That is the
integers 0-127 mean what ASCII says they mean.  But integers 128 and
above are specific to the character set.

Many of these fit entirely into 8 bits, using ASCII as 0-127, while
specifying what 128-255 mean, and not using anything above 255.
Thus, these are single-byte (or octet if you prefer) character sets.
One important one (since Unicode is a superset of it) is the ISO 8859-1
character set.

=head2 ISO 8859

The ISO 8859-I<B<$n>> are a collection of character code sets from the
International Organization for Standardization (ISO), each of which adds
characters to the ASCII set that are typically found in various
languages, many of which are based on the Roman, or Latin, alphabet.
Most are for European languages, but there are also ones for Arabic,
Greek, Hebrew, and Thai.  There are good references on the web about
all these.

=head2 Latin 1 (ISO 8859-1)

A particular 8-bit extension to ASCII that includes grave and acute
accented Latin characters.  Languages that can employ ISO 8859-1
include all the languages covered by ASCII as well as Afrikaans,
Albanian, Basque, Catalan, Danish, Faroese, Finnish, Norwegian,
Portuguese, Spanish, and Swedish.  Dutch is covered albeit without
the ij ligature.  French is covered too but without the oe ligature.
German can use ISO 8859-1 but must do so without German-style
quotation marks.  This set is based on Western European extensions
to ASCII and is commonly encountered in world wide web work.
In IBM character code set identification terminology, ISO 8859-1 is
also known as CCSID 819 (or sometimes 0819 or even 00819).

=head2 EBCDIC

The Extended Binary Coded Decimal Interchange Code refers to a
large collection of single- and multi-byte coded character sets that are
quite different from ASCII and ISO 8859-1, and are all slightly
different from each other; they typically run on host computers.  The
EBCDIC encodings derive from 8-bit byte extensions of Hollerith punched
card encodings, which long predate ASCII.  The layout on the
cards was such that high bits were set for the upper and lower case
alphabetic
characters C<[a-z]> and C<[A-Z]>, but there were gaps within each Latin
alphabet range, visible in the table L<below|/recipe 3>.  These gaps can
cause complications.

Some IBM EBCDIC character sets may be known by character code set
identification numbers (CCSID numbers) or code page numbers.

Perl can be compiled on platforms that run any of three commonly used EBCDIC
character sets, listed below.

=head3 The 13 variant characters

Among IBM EBCDIC character code sets there are 13 characters that
are often mapped to different integer values.  Those characters
are known as the 13 "variant" characters and are:

    \ [ ] { } ^ ~ ! # | $ @ `

When Perl is compiled for a platform, it looks at all of these characters to
guess which EBCDIC character set the platform uses, and adapts itself
accordingly to that platform.  If the platform uses a character set that is not
one of the three Perl knows about, Perl will either fail to compile, or
mistakenly and silently choose one of the three.

=head3 EBCDIC code sets recognized by Perl

=over

=item B<0037>

Character code set ID 0037 is a mapping of the ASCII plus Latin-1
characters (i.e. ISO 8859-1) to an EBCDIC set.  0037 is used
in North American English locales on the OS/400 operating system
that runs on AS/400 computers.  CCSID 0037 differs from ISO 8859-1
in 236 places; in other words they agree on only 20 code point values.

=item B<1047>

Character code set ID 1047 is also a mapping of the ASCII plus
Latin-1 characters (i.e. ISO 8859-1) to an EBCDIC set.  1047 is
used under Unix System Services for OS/390 or z/OS, and OpenEdition
for VM/ESA.  CCSID 1047 differs from CCSID 0037 in eight places,
and from ISO 8859-1 in 236.

=item B<POSIX-BC>

The EBCDIC code page in use on Siemens' BS2000 system is distinct from
1047 and 0037.  It is identified below as the POSIX-BC set.
Like 0037 and 1047, it is the same as ISO 8859-1 in 20 code point
values.

=back

=head2 Unicode code points versus EBCDIC code points

In Unicode terminology a I<code point> is the number assigned to a
character: for example, in EBCDIC the character "A" is usually assigned
the number 193.  In Unicode, the character "A" is assigned the number 65.
All the code points in ASCII and Latin-1 (ISO 8859-1) have the same
meaning in Unicode.  All three of the recognized EBCDIC code sets have
256 code points, and in each code set, all 256 code points are mapped to
equivalent Latin1 code points.  Obviously, "A" will map to "A", "B" =>
"B", "%" => "%", etc., for all printable characters in Latin1 and these
code pages.

It also turns out that EBCDIC has nearly precise equivalents for the
ASCII/Latin1 C0 controls and the DELETE control.  (The C0 controls are
those whose ASCII code points are 0..0x1F; things like TAB, ACK, BEL,
etc.)  A mapping is set up between these ASCII/EBCDIC controls.  There
isn't such a precise mapping between the C1 controls on ASCII platforms
and the remaining EBCDIC controls.  What has been done is to map these
controls, mostly arbitrarily, to some otherwise unmatched character in
the other character set.  Most of these are very very rarely used
nowadays in EBCDIC anyway, and their names have been dropped, without
much complaint.  For example the EO (Eight Ones) EBCDIC control
(consisting of eight one bits = 0xFF) is mapped to the C1 APC control
(0x9F), and you can't use the name "EO".

The EBCDIC controls provide three possible line terminator characters,
CR (0x0D), LF (0x25), and NL (0x15).  On ASCII platforms, the symbols
"NL" and "LF" refer to the same character, but in strict EBCDIC
terminology they are different ones.  The EBCDIC NL is mapped to the C1
control called "NEL" ("Next Line"; here's a case where the mapping makes
quite a bit of sense, and hence isn't just arbitrary).  On some EBCDIC
platforms, this NL or NEL is the typical line terminator.  This is true
of z/OS and BS2000.  In these platforms, the C compilers will swap the
LF and NEL code points, so that C<"\n"> is 0x15, and refers to NL.  Perl
does that too; you can see it in the code chart L<below|/recipe 3>.
This makes things generally "just work" without you even having to be
aware that there is a swap.

=head2 Unicode and UTF

UTF stands for "Unicode Transformation Format".
UTF-8 is an encoding of Unicode into a sequence of 8-bit byte chunks, based on
ASCII and Latin-1.
The length of a sequence required to represent a Unicode code point
depends on the ordinal number of that code point,
with larger numbers requiring more bytes.
UTF-EBCDIC is like UTF-8, but based on EBCDIC.
They are enough alike that often, casual usage will conflate the two
terms, and use "UTF-8" to mean both the UTF-8 found on ASCII platforms,
and the UTF-EBCDIC found on EBCDIC ones.

You may see the term "invariant" character or code point.
This simply means that the character has the same numeric
value and representation when encoded in UTF-8 (or UTF-EBCDIC) as when
not.  (Note that this is a very different concept from L</The 13 variant
characters> mentioned above.  Careful prose will use the term "UTF-8
invariant" instead of just "invariant", but most often you'll see just
"invariant".) For example, the ordinal value of "A" is 193 in most
EBCDIC code pages, and also is 193 when encoded in UTF-EBCDIC.  All
UTF-8 (or UTF-EBCDIC) variant code points occupy at least two bytes when
encoded in UTF-8 (or UTF-EBCDIC); by definition, the UTF-8 (or
UTF-EBCDIC) invariant code points are exactly one byte whether encoded
in UTF-8 (or UTF-EBCDIC), or not.  (By now you see why people typically
just say "UTF-8" when they also mean "UTF-EBCDIC".  For the rest of this
document, we'll mostly be casual about it too.)
In ASCII UTF-8, the code points corresponding to the lowest 128
ordinal numbers (0 - 127: the ASCII characters) are invariant.
In UTF-EBCDIC, there are 160 invariant characters.
(If you care, the EBCDIC invariants are those characters
which have ASCII equivalents, plus those that correspond to
the C1 controls (128 - 159 on ASCII platforms).)

A string encoded in UTF-EBCDIC may be longer (but never shorter) than
one encoded in UTF-8.  Perl extends UTF-8 so that it can encode code
points above the Unicode maximum of U+10FFFF.  It extends UTF-EBCDIC as
well, but due to the inherent limitations in UTF-EBCDIC, the maximum
code point expressible is U+7FFF_FFFF, even if the word size is more
than 32 bits.

UTF-EBCDIC is defined by
L<Unicode Technical Report #16|http://www.unicode.org/reports/tr16>.
It is defined based on CCSID 1047, not allowing for the differences for
other code pages.  This allows for easy interchange of text between
computers running different code pages, but makes it unusable, without
adaptation, for Perl on those other code pages.

The reason for this unusability is that a fundamental assumption of Perl
is that the characters it cares about for parsing and lexical analysis
are the same whether or not the text is in UTF-8.  For example, Perl
expects the character C<"["> to have the same representation, no matter
if the string containing it (or program text) is UTF-8 encoded or not.
To ensure this, Perl adapts UTF-EBCDIC to the particular code page so
that all characters it expects to be UTF-8 invariant are in fact UTF-8
invariant.  This means that text generated on a computer running one
version of Perl's UTF-EBCDIC has to be translated to be intelligible to
a computer running another.

=head2 Using Encode

Starting from Perl 5.8 you can use the standard module Encode
to translate from EBCDIC to Latin-1 code points.
Encode knows about more EBCDIC character sets than Perl can currently
be compiled to run on.

   use Encode 'from_to';

   my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' );

   # $a is in EBCDIC code points
   from_to($a, $ebcdic{ord '^'}, 'latin1');
   # $a is ISO 8859-1 code points

and from Latin-1 code points to EBCDIC code points

   use Encode 'from_to';

   my %ebcdic = ( 176 => 'cp37', 95 => 'cp1047', 106 => 'posix-bc' );

   # $a is ISO 8859-1 code points
   from_to($a, 'latin1', $ebcdic{ord '^'});
   # $a is in EBCDIC code points

For doing I/O it is suggested that you use the autotranslating features
of PerlIO, see L<perluniintro>.

Since version 5.8 Perl uses the PerlIO I/O library.  This enables
you to use different encodings per IO channel.  For example you may use

    use Encode;
    open($f, ">:encoding(ascii)", "test.ascii");
    print $f "Hello World!\n";
    open($f, ">:encoding(cp37)", "test.ebcdic");
    print $f "Hello World!\n";
    open($f, ">:encoding(latin1)", "test.latin1");
    print $f "Hello World!\n";
    open($f, ">:encoding(utf8)", "test.utf8");
    print $f "Hello World!\n";

to get four files containing "Hello World!\n" in ASCII, CP 0037 EBCDIC,
ISO 8859-1 (Latin-1) (in this example identical to ASCII since only ASCII
characters were printed), and
UTF-EBCDIC (in this example identical to normal EBCDIC since only characters
that don't differ between EBCDIC and UTF-EBCDIC were printed).  See the
documentation of L<Encode::PerlIO> for details.

As the PerlIO layer uses raw IO (bytes) internally, all this totally
ignores things like the type of your filesystem (ASCII or EBCDIC).

=head1 SINGLE OCTET TABLES

The following tables list the ASCII and Latin 1 ordered sets including
the subsets: C0 controls (0..31), ASCII graphics (32..7e), delete (7f),
C1 controls (80..9f), and Latin-1 (a.k.a. ISO 8859-1) (a0..ff).  In the
table names of the Latin 1
extensions to ASCII have been labelled with character names roughly
corresponding to I<The Unicode Standard, Version 6.1> albeit with
substitutions such as C<s/LATIN//> and C<s/VULGAR//> in all cases;
S<C<s/CAPITAL LETTER//>> in some cases; and
S<C<s/SMALL LETTER ([A-Z])/\l$1/>> in some other
cases.  Controls are listed using their Unicode 6.2 abbreviations.
The differences between the 0037 and 1047 sets are
flagged with C<**>.  The differences between the 1047 and POSIX-BC sets
are flagged with C<##.>  All C<ord()> numbers listed are decimal.  If you
would rather see this table listing octal values, then run the table
(that is, the pod source text of this document, since this recipe may not
work with a pod2_other_format translation) through:

=over 4

=item recipe 0

=back

    perl -ne 'if(/(.{29})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \
     -e '{printf("%s%-5.03o%-5.03o%-5.03o%.03o\n",$1,$2,$3,$4,$5)}' \
     perlebcdic.pod

If you want to retain the UTF-x code points then in script form you
might want to write:

=over 4

=item recipe 1

=back

 open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!";
 while (<FH>) {
     if (/(.{29})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)
                                                     \s+(\d+)\.?(\d*)/x)
     {
         if ($7 ne '' && $9 ne '') {
             printf(
                "%s%-5.03o%-5.03o%-5.03o%-5.03o%-3o.%-5o%-3o.%.03o\n",
                                            $1,$2,$3,$4,$5,$6,$7,$8,$9);
         }
         elsif ($7 ne '') {
             printf("%s%-5.03o%-5.03o%-5.03o%-5.03o%-3o.%-5o%.03o\n",
                                           $1,$2,$3,$4,$5,$6,$7,$8);
         }
         else {
             printf("%s%-5.03o%-5.03o%-5.03o%-5.03o%-5.03o%.03o\n",
                                                $1,$2,$3,$4,$5,$6,$8);
         }
     }
 }

If you would rather see this table listing hexadecimal values then
run the table through:

=over 4

=item recipe 2

=back

    perl -ne 'if(/(.{29})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)' \
     -e '{printf("%s%-5.02X%-5.02X%-5.02X%.02X\n",$1,$2,$3,$4,$5)}' \
     perlebcdic.pod

Or, in order to retain the UTF-x code points in hexadecimal:

=over 4

=item recipe 3

=back

 open(FH,"<perlebcdic.pod") or die "Could not open perlebcdic.pod: $!";
 while (<FH>) {
     if (/(.{29})(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\.?(\d*)
                                                     \s+(\d+)\.?(\d*)/x)
     {
         if ($7 ne '' && $9 ne '') {
             printf(
                "%s%-5.02X%-5.02X%-5.02X%-5.02X%-2X.%-6.02X%02X.%02X\n",
                                           $1,$2,$3,$4,$5,$6,$7,$8,$9);
         }
         elsif ($7 ne '') {
             printf("%s%-5.02X%-5.02X%-5.02X%-5.02X%-2X.%-6.02X%02X\n",
                                              $1,$2,$3,$4,$5,$6,$7,$8);
         }
         else {
             printf("%s%-5.02X%-5.02X%-5.02X%-5.02X%-5.02X%02X\n",
                                                  $1,$2,$3,$4,$5,$6,$8);
         }
     }
 }


                          ISO
                         8859-1             POS-         CCSID
                         CCSID  CCSID CCSID IX-          1047
  chr                     0819   0037 1047  BC  UTF-8  UTF-EBCDIC
 ---------------------------------------------------------------------
 <NUL>                       0    0    0    0    0        0
 <SOH>                       1    1    1    1    1        1
 <STX>                       2    2    2    2    2        2
 <ETX>                       3    3    3    3    3        3
 <EOT>                       4    55   55   55   4        55
 <ENQ>                       5    45   45   45   5        45
 <ACK>                       6    46   46   46   6        46
 <BEL>                       7    47   47   47   7        47
 <BS>                        8    22   22   22   8        22
 <HT>                        9    5    5    5    9        5
 <LF>                        10   37   21   21   10       21  **
 <VT>                        11   11   11   11   11       11
 <FF>                        12   12   12   12   12       12
 <CR>                        13   13   13   13   13       13
 <SO>                        14   14   14   14   14       14
 <SI>                        15   15   15   15   15       15
 <DLE>                       16   16   16   16   16       16
 <DC1>                       17   17   17   17   17       17
 <DC2>                       18   18   18   18   18       18
 <DC3>                       19   19   19   19   19       19
 <DC4>                       20   60   60   60   20       60
 <NAK>                       21   61   61   61   21       61
 <SYN>                       22   50   50   50   22       50
 <ETB>                       23   38   38   38   23       38
 <CAN>                       24   24   24   24   24       24
 <EOM>                       25   25   25   25   25       25
 <SUB>                       26   63   63   63   26       63
 <ESC>                       27   39   39   39   27       39
 <FS>                        28   28   28   28   28       28
 <GS>                        29   29   29   29   29       29
 <RS>                        30   30   30   30   30       30
 <US>                        31   31   31   31   31       31
 <SPACE>                     32   64   64   64   32       64
 !                           33   90   90   90   33       90
 "                           34   127  127  127  34       127
 #                           35   123  123  123  35       123
 $                           36   91   91   91   36       91
 %                           37   108  108  108  37       108
 &                           38   80   80   80   38       80
 '                           39   125  125  125  39       125
 (                           40   77   77   77   40       77
 )                           41   93   93   93   41       93
 *                           42   92   92   92   42       92
 +                           43   78   78   78   43       78
 ,                           44   107  107  107  44       107
 -                           45   96   96   96   45       96
 .                           46   75   75   75   46       75
 /                           47   97   97   97   47       97
 0                           48   240  240  240  48       240
 1                           49   241  241  241  49       241
 2                           50   242  242  242  50       242
 3                           51   243  243  243  51       243
 4                           52   244  244  244  52       244
 5                           53   245  245  245  53       245
 6                           54   246  246  246  54       246
 7                           55   247  247  247  55       247
 8                           56   248  248  248  56       248
 9                           57   249  249  249  57       249
 :                           58   122  122  122  58       122
 ;                           59   94   94   94   59       94
 <                           60   76   76   76   60       76
 =                           61   126  126  126  61       126
 >                           62   110  110  110  62       110
 ?                           63   111  111  111  63       111
 @                           64   124  124  124  64       124
 A                           65   193  193  193  65       193
 B                           66   194  194  194  66       194
 C                           67   195  195  195  67       195
 D                           68   196  196  196  68       196
 E                           69   197  197  197  69       197
 F                           70   198  198  198  70       198
 G                           71   199  199  199  71       199
 H                           72   200  200  200  72       200
 I                           73   201  201  201  73       201
 J                           74   209  209  209  74       209
 K                           75   210  210  210  75       210
 L                           76   211  211  211  76       211
 M                           77   212  212  212  77       212
 N                           78   213  213  213  78       213
 O                           79   214  214  214  79       214
 P                           80   215  215  215  80       215
 Q                           81   216  216  216  81       216
 R                           82   217  217  217  82       217
 S                           83   226  226  226  83       226
 T                           84   227  227  227  84       227
 U                           85   228  228  228  85       228
 V                           86   229  229  229  86       229
 W                           87   230  230  230  87       230
 X                           88   231  231  231  88       231
 Y                           89   232  232  232  89       232
 Z                           90   233  233  233  90       233
 [                           91   186  173  187  91       173  ** ##
 \                           92   224  224  188  92       224  ##
 ]                           93   187  189  189  93       189  **
 ^                           94   176  95   106  94       95   ** ##
 _                           95   109  109  109  95       109
 `                           96   121  121  74   96       121  ##
 a                           97   129  129  129  97       129
 b                           98   130  130  130  98       130
 c                           99   131  131  131  99       131
 d                           100  132  132  132  100      132
 e                           101  133  133  133  101      133
 f                           102  134  134  134  102      134
 g                           103  135  135  135  103      135
 h                           104  136  136  136  104      136
 i                           105  137  137  137  105      137
 j                           106  145  145  145  106      145
 k                           107  146  146  146  107      146
 l                           108  147  147  147  108      147
 m                           109  148  148  148  109      148
 n                           110  149  149  149  110      149
 o                           111  150  150  150  111      150
 p                           112  151  151  151  112      151
 q                           113  152  152  152  113      152
 r                           114  153  153  153  114      153
 s                           115  162  162  162  115      162
 t                           116  163  163  163  116      163
 u                           117  164  164  164  117      164
 v                           118  165  165  165  118      165
 w                           119  166  166  166  119      166
 x                           120  167  167  167  120      167
 y                           121  168  168  168  121      168
 z                           122  169  169  169  122      169
 {                           123  192  192  251  123      192  ##
 |                           124  79   79   79   124      79
 }                           125  208  208  253  125      208  ##
 ~                           126  161  161  255  126      161  ##
 <DEL>                       127  7    7    7    127      7
 <PAD>                       128  32   32   32   194.128  32
 <HOP>                       129  33   33   33   194.129  33
 <BPH>                       130  34   34   34   194.130  34
 <NBH>                       131  35   35   35   194.131  35
 <IND>                       132  36   36   36   194.132  36
 <NEL>                       133  21   37   37   194.133  37   **
 <SSA>                       134  6    6    6    194.134  6
 <ESA>                       135  23   23   23   194.135  23
 <HTS>                       136  40   40   40   194.136  40
 <HTJ>                       137  41   41   41   194.137  41
 <VTS>                       138  42   42   42   194.138  42
 <PLD>                       139  43   43   43   194.139  43
 <PLU>                       140  44   44   44   194.140  44
 <RI>                        141  9    9    9    194.141  9
 <SS2>                       142  10   10   10   194.142  10
 <SS3>                       143  27   27   27   194.143  27
 <DCS>                       144  48   48   48   194.144  48
 <PU1>                       145  49   49   49   194.145  49
 <PU2>                       146  26   26   26   194.146  26
 <STS>                       147  51   51   51   194.147  51
 <CCH>                       148  52   52   52   194.148  52
 <MW>                        149  53   53   53   194.149  53
 <SPA>                       150  54   54   54   194.150  54
 <EPA>                       151  8    8    8    194.151  8
 <SOS>                       152  56   56   56   194.152  56
 <SGC>                       153  57   57   57   194.153  57
 <SCI>                       154  58   58   58   194.154  58
 <CSI>                       155  59   59   59   194.155  59
 <ST>                        156  4    4    4    194.156  4
 <OSC>                       157  20   20   20   194.157  20
 <PM>                        158  62   62   62   194.158  62
 <APC>                       159  255  255  95   194.159  255      ##
 <NON-BREAKING SPACE>        160  65   65   65   194.160  128.65
 <INVERTED "!" >             161  170  170  170  194.161  128.66
 <CENT SIGN>                 162  74   74   176  194.162  128.67   ##
 <POUND SIGN>                163  177  177  177  194.163  128.68
 <CURRENCY SIGN>             164  159  159  159  194.164  128.69
 <YEN SIGN>                  165  178  178  178  194.165  128.70
 <BROKEN BAR>                166  106  106  208  194.166  128.71   ##
 <SECTION SIGN>              167  181  181  181  194.167  128.72
 <DIAERESIS>                 168  189  187  121  194.168  128.73   ** ##
 <COPYRIGHT SIGN>            169  180  180  180  194.169  128.74
 <FEMININE ORDINAL>          170  154  154  154  194.170  128.81
 <LEFT POINTING GUILLEMET>   171  138  138  138  194.171  128.82
 <NOT SIGN>                  172  95   176  186  194.172  128.83   ** ##
 <SOFT HYPHEN>               173  202  202  202  194.173  128.84
 <REGISTERED TRADE MARK>     174  175  175  175  194.174  128.85
 <MACRON>                    175  188  188  161  194.175  128.86   ##
 <DEGREE SIGN>               176  144  144  144  194.176  128.87
 <PLUS-OR-MINUS SIGN>        177  143  143  143  194.177  128.88
 <SUPERSCRIPT TWO>           178  234  234  234  194.178  128.89
 <SUPERSCRIPT THREE>         179  250  250  250  194.179  128.98
 <ACUTE ACCENT>              180  190  190  190  194.180  128.99
 <MICRO SIGN>                181  160  160  160  194.181  128.100
 <PARAGRAPH SIGN>            182  182  182  182  194.182  128.101
 <MIDDLE DOT>                183  179  179  179  194.183  128.102
 <CEDILLA>                   184  157  157  157  194.184  128.103
 <SUPERSCRIPT ONE>           185  218  218  218  194.185  128.104
 <MASC. ORDINAL INDICATOR>   186  155  155  155  194.186  128.105
 <RIGHT POINTING GUILLEMET>  187  139  139  139  194.187  128.106
 <FRACTION ONE QUARTER>      188  183  183  183  194.188  128.112
 <FRACTION ONE HALF>         189  184  184  184  194.189  128.113
 <FRACTION THREE QUARTERS>   190  185  185  185  194.190  128.114
 <INVERTED QUESTION MARK>    191  171  171  171  194.191  128.115
 <A WITH GRAVE>              192  100  100  100  195.128  138.65
 <A WITH ACUTE>              193  101  101  101  195.129  138.66
 <A WITH CIRCUMFLEX>         194  98   98   98   195.130  138.67
 <A WITH TILDE>              195  102  102  102  195.131  138.68
 <A WITH DIAERESIS>          196  99   99   99   195.132  138.69
 <A WITH RING ABOVE>         197  103  103  103  195.133  138.70
 <CAPITAL LIGATURE AE>       198  158  158  158  195.134  138.71
 <C WITH CEDILLA>            199  104  104  104  195.135  138.72
 <E WITH GRAVE>              200  116  116  116  195.136  138.73
 <E WITH ACUTE>              201  113  113  113  195.137  138.74
 <E WITH CIRCUMFLEX>         202  114  114  114  195.138  138.81
 <E WITH DIAERESIS>          203  115  115  115  195.139  138.82
 <I WITH GRAVE>              204  120  120  120  195.140  138.83
 <I WITH ACUTE>              205  117  117  117  195.141  138.84
 <I WITH CIRCUMFLEX>         206  118  118  118  195.142  138.85
 <I WITH DIAERESIS>          207  119  119  119  195.143  138.86
 <CAPITAL LETTER ETH>        208  172  172  172  195.144  138.87
 <N WITH TILDE>              209  105  105  105  195.145  138.88
 <O WITH GRAVE>              210  237  237  237  195.146  138.89
 <O WITH ACUTE>              211  238  238  238  195.147  138.98
 <O WITH CIRCUMFLEX>         212  235  235  235  195.148  138.99
 <O WITH TILDE>              213  239  239  239  195.149  138.100
 <O WITH DIAERESIS>          214  236  236  236  195.150  138.101
 <MULTIPLICATION SIGN>       215  191  191  191  195.151  138.102
 <O WITH STROKE>             216  128  128  128  195.152  138.103
 <U WITH GRAVE>              217  253  253  224  195.153  138.104  ##
 <U WITH ACUTE>              218  254  254  254  195.154  138.105
 <U WITH CIRCUMFLEX>         219  251  251  221  195.155  138.106  ##
 <U WITH DIAERESIS>          220  252  252  252  195.156  138.112
 <Y WITH ACUTE>              221  173  186  173  195.157  138.113  ** ##
 <CAPITAL LETTER THORN>      222  174  174  174  195.158  138.114
 <SMALL LETTER SHARP S>      223  89   89   89   195.159  138.115
 <a WITH GRAVE>              224  68   68   68   195.160  139.65
 <a WITH ACUTE>              225  69   69   69   195.161  139.66
 <a WITH CIRCUMFLEX>         226  66   66   66   195.162  139.67
 <a WITH TILDE>              227  70   70   70   195.163  139.68
 <a WITH DIAERESIS>          228  67   67   67   195.164  139.69
 <a WITH RING ABOVE>         229  71   71   71   195.165  139.70
 <SMALL LIGATURE ae>         230  156  156  156  195.166  139.71
 <c WITH CEDILLA>            231  72   72   72   195.167  139.72
 <e WITH GRAVE>              232  84   84   84   195.168  139.73
 <e WITH ACUTE>              233  81   81   81   195.169  139.74
 <e WITH CIRCUMFLEX>         234  82   82   82   195.170  139.81
 <e WITH DIAERESIS>          235  83   83   83   195.171  139.82
 <i WITH GRAVE>              236  88   88   88   195.172  139.83
 <i WITH ACUTE>              237  85   85   85   195.173  139.84
 <i WITH CIRCUMFLEX>         238  86   86   86   195.174  139.85
 <i WITH DIAERESIS>          239  87   87   87   195.175  139.86
 <SMALL LETTER eth>          240  140  140  140  195.176  139.87
 <n WITH TILDE>              241  73   73   73   195.177  139.88
 <o WITH GRAVE>              242  205  205  205  195.178  139.89
 <o WITH ACUTE>              243  206  206  206  195.179  139.98
 <o WITH CIRCUMFLEX>         244  203  203  203  195.180  139.99
 <o WITH TILDE>              245  207  207  207  195.181  139.100
 <o WITH DIAERESIS>          246  204  204  204  195.182  139.101
 <DIVISION SIGN>             247  225  225  225  195.183  139.102
 <o WITH STROKE>             248  112  112  112  195.184  139.103
 <u WITH GRAVE>              249  221  221  192  195.185  139.104  ##
 <u WITH ACUTE>              250  222  222  222  195.186  139.105
 <u WITH CIRCUMFLEX>         251  219  219  219  195.187  139.106
 <u WITH DIAERESIS>          252  220  220  220  195.188  139.112
 <y WITH ACUTE>              253  141  141  141  195.189  139.113
 <SMALL LETTER thorn>        254  142  142  142  195.190  139.114
 <y WITH DIAERESIS>          255  223  223  223  195.191  139.115

If you would rather see the above table in CCSID 0037 order rather than
ASCII + Latin-1 order then run the table through:

=over 4

=item recipe 4

=back

 perl \
    -ne 'if(/.{29}\d{1,3}\s{2,4}\d{1,3}\s{2,4}\d{1,3}\s{2,4}\d{1,3}/)'\
     -e '{push(@l,$_)}' \
     -e 'END{print map{$_->[0]}' \
     -e '          sort{$a->[1] <=> $b->[1]}' \
     -e '          map{[$_,substr($_,34,3)]}@l;}' perlebcdic.pod

If you would rather see it in CCSID 1047 order then change the number
34 in the last line to 39, like this:

=over 4

=item recipe 5

=back

 perl \
    -ne 'if(/.{29}\d{1,3}\s{2,4}\d{1,3}\s{2,4}\d{1,3}\s{2,4}\d{1,3}/)'\
    -e '{push(@l,$_)}' \
    -e 'END{print map{$_->[0]}' \
    -e '          sort{$a->[1] <=> $b->[1]}' \
    -e '          map{[$_,substr($_,39,3)]}@l;}' perlebcdic.pod

If you would rather see it in POSIX-BC order then change the number
34 in the last line to 44, like this:

=over 4

=item recipe 6

=back

 perl \
    -ne 'if(/.{29}\d{1,3}\s{2,4}\d{1,3}\s{2,4}\d{1,3}\s{2,4}\d{1,3}/)'\
     -e '{push(@l,$_)}' \
     -e 'END{print map{$_->[0]}' \
     -e '          sort{$a->[1] <=> $b->[1]}' \
     -e '          map{[$_,substr($_,44,3)]}@l;}' perlebcdic.pod

=head2 Table in hex, sorted in 1047 order

Since this document was first written, the convention has become more
and more to use hexadecimal notation for code points.  To do this with
the recipes and to also sort is a multi-step process, so here, for
convenience, is the table from above, re-sorted to be in Code Page 1047
order, and using hex notation.

                          ISO
                         8859-1             POS-         CCSID
                         CCSID  CCSID CCSID IX-          1047
  chr                     0819   0037 1047  BC  UTF-8  UTF-EBCDIC
 ---------------------------------------------------------------------
 <NUL>                       00   00   00   00   00       00
 <SOH>                       01   01   01   01   01       01
 <STX>                       02   02   02   02   02       02
 <ETX>                       03   03   03   03   03       03
 <ST>                        9C   04   04   04   C2.9C    04
 <HT>                        09   05   05   05   09       05
 <SSA>                       86   06   06   06   C2.86    06
 <DEL>                       7F   07   07   07   7F       07
 <EPA>                       97   08   08   08   C2.97    08
 <RI>                        8D   09   09   09   C2.8D    09
 <SS2>                       8E   0A   0A   0A   C2.8E    0A
 <VT>                        0B   0B   0B   0B   0B       0B
 <FF>                        0C   0C   0C   0C   0C       0C
 <CR>                        0D   0D   0D   0D   0D       0D
 <SO>                        0E   0E   0E   0E   0E       0E
 <SI>                        0F   0F   0F   0F   0F       0F
 <DLE>                       10   10   10   10   10       10
 <DC1>                       11   11   11   11   11       11
 <DC2>                       12   12   12   12   12       12
 <DC3>                       13   13   13   13   13       13
 <OSC>                       9D   14   14   14   C2.9D    14
 <LF>                        0A   25   15   15   0A       15    **
 <BS>                        08   16   16   16   08       16
 <ESA>                       87   17   17   17   C2.87    17
 <CAN>                       18   18   18   18   18       18
 <EOM>                       19   19   19   19   19       19
 <PU2>                       92   1A   1A   1A   C2.92    1A
 <SS3>                       8F   1B   1B   1B   C2.8F    1B
 <FS>                        1C   1C   1C   1C   1C       1C
 <GS>                        1D   1D   1D   1D   1D       1D
 <RS>                        1E   1E   1E   1E   1E       1E
 <US>                        1F   1F   1F   1F   1F       1F
 <PAD>                       80   20   20   20   C2.80    20
 <HOP>                       81   21   21   21   C2.81    21
 <BPH>                       82   22   22   22   C2.82    22
 <NBH>                       83   23   23   23   C2.83    23
 <IND>                       84   24   24   24   C2.84    24
 <NEL>                       85   15   25   25   C2.85    25     **
 <ETB>                       17   26   26   26   17       26
 <ESC>                       1B   27   27   27   1B       27
 <HTS>                       88   28   28   28   C2.88    28
 <HTJ>                       89   29   29   29   C2.89    29
 <VTS>                       8A   2A   2A   2A   C2.8A    2A
 <PLD>                       8B   2B   2B   2B   C2.8B    2B
 <PLU>                       8C   2C   2C   2C   C2.8C    2C
 <ENQ>                       05   2D   2D   2D   05       2D
 <ACK>                       06   2E   2E   2E   06       2E
 <BEL>                       07   2F   2F   2F   07       2F
 <DCS>                       90   30   30   30   C2.90    30
 <PU1>                       91   31   31   31   C2.91    31
 <SYN>                       16   32   32   32   16       32
 <STS>                       93   33   33   33   C2.93    33
 <CCH>                       94   34   34   34   C2.94    34
 <MW>                        95   35   35   35   C2.95    35
 <SPA>                       96   36   36   36   C2.96    36
 <EOT>                       04   37   37   37   04       37
 <SOS>                       98   38   38   38   C2.98    38
 <SGC>                       99   39   39   39   C2.99    39
 <SCI>                       9A   3A   3A   3A   C2.9A    3A
 <CSI>                       9B   3B   3B   3B   C2.9B    3B
 <DC4>                       14   3C   3C   3C   14       3C
 <NAK>                       15   3D   3D   3D   15       3D
 <PM>                        9E   3E   3E   3E   C2.9E    3E
 <SUB>                       1A   3F   3F   3F   1A       3F
 <SPACE>                     20   40   40   40   20       40
 <NON-BREAKING SPACE>        A0   41   41   41   C2.A0    80.41
 <a WITH CIRCUMFLEX>         E2   42   42   42   C3.A2    8B.43
 <a WITH DIAERESIS>          E4   43   43   43   C3.A4    8B.45
 <a WITH GRAVE>              E0   44   44   44   C3.A0    8B.41
 <a WITH ACUTE>              E1   45   45   45   C3.A1    8B.42
 <a WITH TILDE>              E3   46   46   46   C3.A3    8B.44
 <a WITH RING ABOVE>         E5   47   47   47   C3.A5    8B.46
 <c WITH CEDILLA>            E7   48   48   48   C3.A7    8B.48
 <n WITH TILDE>              F1   49   49   49   C3.B1    8B.58
 <CENT SIGN>                 A2   4A   4A   B0   C2.A2    80.43  ##
 .                           2E   4B   4B   4B   2E       4B
 <                           3C   4C   4C   4C   3C       4C
 (                           28   4D   4D   4D   28       4D
 +                           2B   4E   4E   4E   2B       4E
 |                           7C   4F   4F   4F   7C       4F
 &                           26   50   50   50   26       50
 <e WITH ACUTE>              E9   51   51   51   C3.A9    8B.4A
 <e WITH CIRCUMFLEX>         EA   52   52   52   C3.AA    8B.51
 <e WITH DIAERESIS>          EB   53   53   53   C3.AB    8B.52
 <e WITH GRAVE>              E8   54   54   54   C3.A8    8B.49
 <i WITH ACUTE>              ED   55   55   55   C3.AD    8B.54
 <i WITH CIRCUMFLEX>         EE   56   56   56   C3.AE    8B.55
 <i WITH DIAERESIS>          EF   57   57   57   C3.AF    8B.56
 <i WITH GRAVE>              EC   58   58   58   C3.AC    8B.53
 <SMALL LETTER SHARP S>      DF   59   59   59   C3.9F    8A.73
 !                           21   5A   5A   5A   21       5A
 $                           24   5B   5B   5B   24       5B
 *                           2A   5C   5C   5C   2A       5C
 )                           29   5D   5D   5D   29       5D
 ;                           3B   5E   5E   5E   3B       5E
 ^                           5E   B0   5F   6A   5E       5F     ** ##
 -                           2D   60   60   60   2D       60
 /                           2F   61   61   61   2F       61
 <A WITH CIRCUMFLEX>         C2   62   62   62   C3.82    8A.43
 <A WITH DIAERESIS>          C4   63   63   63   C3.84    8A.45
 <A WITH GRAVE>              C0   64   64   64   C3.80    8A.41
 <A WITH ACUTE>              C1   65   65   65   C3.81    8A.42
 <A WITH TILDE>              C3   66   66   66   C3.83    8A.44
 <A WITH RING ABOVE>         C5   67   67   67   C3.85    8A.46
 <C WITH CEDILLA>            C7   68   68   68   C3.87    8A.48
 <N WITH TILDE>              D1   69   69   69   C3.91    8A.58
 <BROKEN BAR>                A6   6A   6A   D0   C2.A6    80.47  ##
 ,                           2C   6B   6B   6B   2C       6B
 %                           25   6C   6C   6C   25       6C
 _                           5F   6D   6D   6D   5F       6D
 >                           3E   6E   6E   6E   3E       6E
 ?                           3F   6F   6F   6F   3F       6F
 <o WITH STROKE>             F8   70   70   70   C3.B8    8B.67
 <E WITH ACUTE>              C9   71   71   71   C3.89    8A.4A
 <E WITH CIRCUMFLEX>         CA   72   72   72   C3.8A    8A.51
 <E WITH DIAERESIS>          CB   73   73   73   C3.8B    8A.52
 <E WITH GRAVE>              C8   74   74   74   C3.88    8A.49
 <I WITH ACUTE>              CD   75   75   75   C3.8D    8A.54
 <I WITH CIRCUMFLEX>         CE   76   76   76   C3.8E    8A.55
 <I WITH DIAERESIS>          CF   77   77   77   C3.8F    8A.56
 <I WITH GRAVE>              CC   78   78   78   C3.8C    8A.53
 `                           60   79   79   4A   60       79     ##
 :                           3A   7A   7A   7A   3A       7A
 #                           23   7B   7B   7B   23       7B
 @                           40   7C   7C   7C   40       7C
 '                           27   7D   7D   7D   27       7D
 =                           3D   7E   7E   7E   3D       7E
 "                           22   7F   7F   7F   22       7F
 <O WITH STROKE>             D8   80   80   80   C3.98    8A.67
 a                           61   81   81   81   61       81
 b                           62   82   82   82   62       82
 c                           63   83   83   83   63       83
 d                           64   84   84   84   64       84
 e                           65   85   85   85   65       85
 f                           66   86   86   86   66       86
 g                           67   87   87   87   67       87
 h                           68   88   88   88   68       88
 i                           69   89   89   89   69       89
 <LEFT POINTING GUILLEMET>   AB   8A   8A   8A   C2.AB    80.52
 <RIGHT POINTING GUILLEMET>  BB   8B   8B   8B   C2.BB    80.6A
 <SMALL LETTER eth>          F0   8C   8C   8C   C3.B0    8B.57
 <y WITH ACUTE>              FD   8D   8D   8D   C3.BD    8B.71
 <SMALL LETTER thorn>        FE   8E   8E   8E   C3.BE    8B.72
 <PLUS-OR-MINUS SIGN>        B1   8F   8F   8F   C2.B1    80.58
 <DEGREE SIGN>               B0   90   90   90   C2.B0    80.57
 j                           6A   91   91   91   6A       91
 k                           6B   92   92   92   6B       92
 l                           6C   93   93   93   6C       93
 m                           6D   94   94   94   6D       94
 n                           6E   95   95   95   6E       95
 o                           6F   96   96   96   6F       96
 p                           70   97   97   97   70       97
 q                           71   98   98   98   71       98
 r                           72   99   99   99   72       99
 <FEMININE ORDINAL>          AA   9A   9A   9A   C2.AA    80.51
 <MASC. ORDINAL INDICATOR>   BA   9B   9B   9B   C2.BA    80.69
 <SMALL LIGATURE ae>         E6   9C   9C   9C   C3.A6    8B.47
 <CEDILLA>                   B8   9D   9D   9D   C2.B8    80.67
 <CAPITAL LIGATURE AE>       C6   9E   9E   9E   C3.86    8A.47
 <CURRENCY SIGN>             A4   9F   9F   9F   C2.A4    80.45
 <MICRO SIGN>                B5   A0   A0   A0   C2.B5    80.64
 ~                           7E   A1   A1   FF   7E       A1     ##
 s                           73   A2   A2   A2   73       A2
 t                           74   A3   A3   A3   74       A3
 u                           75   A4   A4   A4   75       A4
 v                           76   A5   A5   A5   76       A5
 w                           77   A6   A6   A6   77       A6
 x                           78   A7   A7   A7   78       A7
 y                           79   A8   A8   A8   79       A8
 z                           7A   A9   A9   A9   7A       A9
 <INVERTED "!" >             A1   AA   AA   AA   C2.A1    80.42
 <INVERTED QUESTION MARK>    BF   AB   AB   AB   C2.BF    80.73
 <CAPITAL LETTER ETH>        D0   AC   AC   AC   C3.90    8A.57
 [                           5B   BA   AD   BB   5B       AD     ** ##
 <CAPITAL LETTER THORN>      DE   AE   AE   AE   C3.9E    8A.72
 <REGISTERED TRADE MARK>     AE   AF   AF   AF   C2.AE    80.55
 <NOT SIGN>                  AC   5F   B0   BA   C2.AC    80.53  ** ##
 <POUND SIGN>                A3   B1   B1   B1   C2.A3    80.44
 <YEN SIGN>                  A5   B2   B2   B2   C2.A5    80.46
 <MIDDLE DOT>                B7   B3   B3   B3   C2.B7    80.66
 <COPYRIGHT SIGN>            A9   B4   B4   B4   C2.A9    80.4A
 <SECTION SIGN>              A7   B5   B5   B5   C2.A7    80.48
 <PARAGRAPH SIGN>            B6   B6   B6   B6   C2.B6    80.65
 <FRACTION ONE QUARTER>      BC   B7   B7   B7   C2.BC    80.70
 <FRACTION ONE HALF>         BD   B8   B8   B8   C2.BD    80.71
 <FRACTION THREE QUARTERS>   BE   B9   B9   B9   C2.BE    80.72
 <Y WITH ACUTE>              DD   AD   BA   AD   C3.9D    8A.71  ** ##
 <DIAERESIS>                 A8   BD   BB   79   C2.A8    80.49  ** ##
 <MACRON>                    AF   BC   BC   A1   C2.AF    80.56  ##
 ]                           5D   BB   BD   BD   5D       BD     **
 <ACUTE ACCENT>              B4   BE   BE   BE   C2.B4    80.63
 <MULTIPLICATION SIGN>       D7   BF   BF   BF   C3.97    8A.66
 {                           7B   C0   C0   FB   7B       C0     ##
 A                           41   C1   C1   C1   41       C1
 B                           42   C2   C2   C2   42       C2
 C                           43   C3   C3   C3   43       C3
 D                           44   C4   C4   C4   44       C4
 E                           45   C5   C5   C5   45       C5
 F                           46   C6   C6   C6   46       C6
 G                           47   C7   C7   C7   47       C7
 H                           48   C8   C8   C8   48       C8
 I                           49   C9   C9   C9   49       C9
 <SOFT HYPHEN>               AD   CA   CA   CA   C2.AD    80.54
 <o WITH CIRCUMFLEX>         F4   CB   CB   CB   C3.B4    8B.63
 <o WITH DIAERESIS>          F6   CC   CC   CC   C3.B6    8B.65
 <o WITH GRAVE>              F2   CD   CD   CD   C3.B2    8B.59
 <o WITH ACUTE>              F3   CE   CE   CE   C3.B3    8B.62
 <o WITH TILDE>              F5   CF   CF   CF   C3.B5    8B.64
 }                           7D   D0   D0   FD   7D       D0     ##
 J                           4A   D1   D1   D1   4A       D1
 K                           4B   D2   D2   D2   4B       D2
 L                           4C   D3   D3   D3   4C       D3
 M                           4D   D4   D4   D4   4D       D4
 N                           4E   D5   D5   D5   4E       D5
 O                           4F   D6   D6   D6   4F       D6
 P                           50   D7   D7   D7   50       D7
 Q                           51   D8   D8   D8   51       D8
 R                           52   D9   D9   D9   52       D9
 <SUPERSCRIPT ONE>           B9   DA   DA   DA   C2.B9    80.68
 <u WITH CIRCUMFLEX>         FB   DB   DB   DB   C3.BB    8B.6A
 <u WITH DIAERESIS>          FC   DC   DC   DC   C3.BC    8B.70
 <u WITH GRAVE>              F9   DD   DD   C0   C3.B9    8B.68  ##
 <u WITH ACUTE>              FA   DE   DE   DE   C3.BA    8B.69
 <y WITH DIAERESIS>          FF   DF   DF   DF   C3.BF    8B.73
 \                           5C   E0   E0   BC   5C       E0     ##
 <DIVISION SIGN>             F7   E1   E1   E1   C3.B7    8B.66
 S                           53   E2   E2   E2   53       E2
 T                           54   E3   E3   E3   54       E3
 U                           55   E4   E4   E4   55       E4
 V                           56   E5   E5   E5   56       E5
 W                           57   E6   E6   E6   57       E6
 X                           58   E7   E7   E7   58       E7
 Y                           59   E8   E8   E8   59       E8
 Z                           5A   E9   E9   E9   5A       E9
 <SUPERSCRIPT TWO>           B2   EA   EA   EA   C2.B2    80.59
 <O WITH CIRCUMFLEX>         D4   EB   EB   EB   C3.94    8A.63
 <O WITH DIAERESIS>          D6   EC   EC   EC   C3.96    8A.65
 <O WITH GRAVE>              D2   ED   ED   ED   C3.92    8A.59
 <O WITH ACUTE>              D3   EE   EE   EE   C3.93    8A.62
 <O WITH TILDE>              D5   EF   EF   EF   C3.95    8A.64
 0                           30   F0   F0   F0   30       F0
 1                           31   F1   F1   F1   31       F1
 2                           32   F2   F2   F2   32       F2
 3                           33   F3   F3   F3   33       F3
 4                           34   F4   F4   F4   34       F4
 5                           35   F5   F5   F5   35       F5
 6                           36   F6   F6   F6   36       F6
 7                           37   F7   F7   F7   37       F7
 8                           38   F8   F8   F8   38       F8
 9                           39   F9   F9   F9   39       F9
 <SUPERSCRIPT THREE>         B3   FA   FA   FA   C2.B3    80.62
 <U WITH CIRCUMFLEX>         DB   FB   FB   DD   C3.9B    8A.6A  ##
 <U WITH DIAERESIS>          DC   FC   FC   FC   C3.9C    8A.70
 <U WITH GRAVE>              D9   FD   FD   E0   C3.99    8A.68  ##
 <U WITH ACUTE>              DA   FE   FE   FE   C3.9A    8A.69
 <APC>                       9F   FF   FF   5F   C2.9F    FF     ##

=head1 IDENTIFYING CHARACTER CODE SETS

It is possible to determine which character set you are operating under.
But first you need to be really really sure you need to do this.  Your
code will be simpler and probably just as portable if you don't have
to test the character set and do different things, depending.  There are
actually only very few circumstances where it's not easy to write
straight-line code portable to all character sets.  See
L<perluniintro/Unicode and EBCDIC> for how to portably specify
characters.

But there are some cases where you may want to know which character set
you are running under.  One possible example is doing
L<sorting|/SORTING> in inner loops where performance is critical.

To determine if you are running under ASCII or EBCDIC, you can use the
return value of C<ord()> or C<chr()> to test one or more character
values.  For example:

    $is_ascii  = "A" eq chr(65);
    $is_ebcdic = "A" eq chr(193);
    $is_ascii  = ord("A") == 65;
    $is_ebcdic = ord("A") == 193;

There's even less need to distinguish between EBCDIC code pages, but to
do so try looking at one or more of the characters that differ between
them.

    $is_ascii           = ord('[') == 91;
    $is_ebcdic_37       = ord('[') == 186;
    $is_ebcdic_1047     = ord('[') == 173;
    $is_ebcdic_POSIX_BC = ord('[') == 187;

However, it would be unwise to write tests such as:

    $is_ascii = "\r" ne chr(13);  #  WRONG
    $is_ascii = "\n" ne chr(10);  #  ILL ADVISED

Obviously the first of these will fail to distinguish most ASCII
platforms from either a CCSID 0037, a 1047, or a POSIX-BC EBCDIC
platform since S<C<"\r" eq chr(13)>> under all of those coded character
sets.  But note too that because C<"\n"> is C<chr(13)> and C<"\r"> is
C<chr(10)> on old Macintosh (which is an ASCII platform) the second
C<$is_ascii> test will lead to trouble there.

To determine whether or not perl was built under an EBCDIC
code page you can use the Config module like so:

    use Config;
    $is_ebcdic = $Config{'ebcdic'} eq 'define';

=head1 CONVERSIONS

=head2 C<utf8::unicode_to_native()> and C<utf8::native_to_unicode()>

These functions take an input numeric code point in one encoding and
return what its equivalent value is in the other.

See L<utf8>.

=head2 tr///

In order to convert a string of characters from one character set to
another a simple list of numbers, such as in the right columns in the
above table, along with Perl's C<tr///> operator is all that is needed.
The data in the table are in ASCII/Latin1 order, hence the EBCDIC columns
provide easy-to-use ASCII/Latin1 to EBCDIC operations that are also easily
reversed.

For example, to convert ASCII/Latin1 to code page 037 take the output of the
second numbers column from the output of recipe 2 (modified to add
C<"\"> characters), and use it in C<tr///> like so:

    $cp_037 =
    '\x00\x01\x02\x03\x37\x2D\x2E\x2F\x16\x05\x25\x0B\x0C\x0D\x0E\x0F' .
    '\x10\x11\x12\x13\x3C\x3D\x32\x26\x18\x19\x3F\x27\x1C\x1D\x1E\x1F' .
    '\x40\x5A\x7F\x7B\x5B\x6C\x50\x7D\x4D\x5D\x5C\x4E\x6B\x60\x4B\x61' .
    '\xF0\xF1\xF2\xF3\xF4\xF5\xF6\xF7\xF8\xF9\x7A\x5E\x4C\x7E\x6E\x6F' .
    '\x7C\xC1\xC2\xC3\xC4\xC5\xC6\xC7\xC8\xC9\xD1\xD2\xD3\xD4\xD5\xD6' .
    '\xD7\xD8\xD9\xE2\xE3\xE4\xE5\xE6\xE7\xE8\xE9\xBA\xE0\xBB\xB0\x6D' .
    '\x79\x81\x82\x83\x84\x85\x86\x87\x88\x89\x91\x92\x93\x94\x95\x96' .
    '\x97\x98\x99\xA2\xA3\xA4\xA5\xA6\xA7\xA8\xA9\xC0\x4F\xD0\xA1\x07' .
    '\x20\x21\x22\x23\x24\x15\x06\x17\x28\x29\x2A\x2B\x2C\x09\x0A\x1B' .
    '\x30\x31\x1A\x33\x34\x35\x36\x08\x38\x39\x3A\x3B\x04\x14\x3E\xFF' .
    '\x41\xAA\x4A\xB1\x9F\xB2\x6A\xB5\xBD\xB4\x9A\x8A\x5F\xCA\xAF\xBC' .
    '\x90\x8F\xEA\xFA\xBE\xA0\xB6\xB3\x9D\xDA\x9B\x8B\xB7\xB8\xB9\xAB' .
    '\x64\x65\x62\x66\x63\x67\x9E\x68\x74\x71\x72\x73\x78\x75\x76\x77' .
    '\xAC\x69\xED\xEE\xEB\xEF\xEC\xBF\x80\xFD\xFE\xFB\xFC\xAD\xAE\x59' .
    '\x44\x45\x42\x46\x43\x47\x9C\x48\x54\x51\x52\x53\x58\x55\x56\x57' .
    '\x8C\x49\xCD\xCE\xCB\xCF\xCC\xE1\x70\xDD\xDE\xDB\xDC\x8D\x8E\xDF';

    my $ebcdic_string = $ascii_string;
    eval '$ebcdic_string =~ tr/\000-\377/' . $cp_037 . '/';

To convert from EBCDIC 037 to ASCII just reverse the order of the tr///
arguments like so:

    my $ascii_string = $ebcdic_string;
    eval '$ascii_string =~ tr/' . $cp_037 . '/\000-\377/';

Similarly one could take the output of the third numbers column from recipe 2
to obtain a C<$cp_1047> table.  The fourth numbers column of the output from
recipe 2 could provide a C<$cp_posix_bc> table suitable for transcoding as
well.

If you wanted to see the inverse tables, you would first have to sort on the
desired numbers column as in recipes 4, 5 or 6, then take the output of the
first numbers column.

=head2 iconv

XPG operability often implies the presence of an I<iconv> utility
available from the shell or from the C library.  Consult your system's
documentation for information on iconv.

On OS/390 or z/OS see the L<iconv(1)> manpage.  One way to invoke the C<iconv>
shell utility from within perl would be to:

    # OS/390 or z/OS example
    $ascii_data = `echo '$ebcdic_data'| iconv -f IBM-1047 -t ISO8859-1`

or the inverse map:

    # OS/390 or z/OS example
    $ebcdic_data = `echo '$ascii_data'| iconv -f ISO8859-1 -t IBM-1047`

For other Perl-based conversion options see the C<Convert::*> modules on CPAN.

=head2 C RTL

The OS/390 and z/OS C run-time libraries provide C<_atoe()> and C<_etoa()> functions.

=head1 OPERATOR DIFFERENCES

The C<..> range operator treats certain character ranges with
care on EBCDIC platforms.  For example the following array
will have twenty six elements on either an EBCDIC platform
or an ASCII platform:

    @alphabet = ('A'..'Z');   #  $#alphabet == 25

The bitwise operators such as & ^ | may return different results
when operating on string or character data in a Perl program running
on an EBCDIC platform than when run on an ASCII platform.  Here is
an example adapted from the one in L<perlop>:

    # EBCDIC-based examples
    print "j p \n" ^ " a h";                      # prints "JAPH\n"
    print "JA" | "  ph\n";                        # prints "japh\n"
    print "JAPH\nJunk" & "\277\277\277\277\277";  # prints "japh\n";
    print 'p N$' ^ " E<H\n";                      # prints "Perl\n";

An interesting property of the 32 C0 control characters
in the ASCII table is that they can "literally" be constructed
as control characters in Perl, e.g. C<(chr(0)> eq C<\c@>)>
C<(chr(1)> eq C<\cA>)>, and so on.  Perl on EBCDIC platforms has been
ported to take C<\c@> to C<chr(0)> and C<\cA> to C<chr(1)>, etc. as well, but the
characters that result depend on which code page you are
using.  The table below uses the standard acronyms for the controls.
The POSIX-BC and 1047 sets are
identical throughout this range and differ from the 0037 set at only
one spot (21 decimal).  Note that the line terminator character
may be generated by C<\cJ> on ASCII platforms but by C<\cU> on 1047 or POSIX-BC
platforms and cannot be generated as a C<"\c.letter."> control character on
0037 platforms.  Note also that C<\c\> cannot be the final element in a string
or regex, as it will absorb the terminator.   But C<\c\I<X>> is a C<FILE
SEPARATOR> concatenated with I<X> for all I<X>.
The outlier C<\c?> on ASCII, which yields a non-C0 control C<DEL>,
yields the outlier control C<APC> on EBCDIC, the one that isn't in the
block of contiguous controls.  Note that a subtlety of this is that
C<\c?> on ASCII platforms is an ASCII character, while it isn't
equivalent to any ASCII character in EBCDIC platforms.

 chr   ord   8859-1    0037    1047 && POSIX-BC
 -----------------------------------------------------------------------
 \c@     0   <NUL>     <NUL>        <NUL>
 \cA     1   <SOH>     <SOH>        <SOH>
 \cB     2   <STX>     <STX>        <STX>
 \cC     3   <ETX>     <ETX>        <ETX>
 \cD     4   <EOT>     <ST>         <ST>
 \cE     5   <ENQ>     <HT>         <HT>
 \cF     6   <ACK>     <SSA>        <SSA>
 \cG     7   <BEL>     <DEL>        <DEL>
 \cH     8   <BS>      <EPA>        <EPA>
 \cI     9   <HT>      <RI>         <RI>
 \cJ    10   <LF>      <SS2>        <SS2>
 \cK    11   <VT>      <VT>         <VT>
 \cL    12   <FF>      <FF>         <FF>
 \cM    13   <CR>      <CR>         <CR>
 \cN    14   <SO>      <SO>         <SO>
 \cO    15   <SI>      <SI>         <SI>
 \cP    16   <DLE>     <DLE>        <DLE>
 \cQ    17   <DC1>     <DC1>        <DC1>
 \cR    18   <DC2>     <DC2>        <DC2>
 \cS    19   <DC3>     <DC3>        <DC3>
 \cT    20   <DC4>     <OSC>        <OSC>
 \cU    21   <NAK>     <NEL>        <LF>              **
 \cV    22   <SYN>     <BS>         <BS>
 \cW    23   <ETB>     <ESA>        <ESA>
 \cX    24   <CAN>     <CAN>        <CAN>
 \cY    25   <EOM>     <EOM>        <EOM>
 \cZ    26   <SUB>     <PU2>        <PU2>
 \c[    27   <ESC>     <SS3>        <SS3>
 \c\X   28   <FS>X     <FS>X        <FS>X
 \c]    29   <GS>      <GS>         <GS>
 \c^    30   <RS>      <RS>         <RS>
 \c_    31   <US>      <US>         <US>
 \c?    *    <DEL>     <APC>        <APC>

C<*> Note: C<\c?> maps to ordinal 127 (C<DEL>) on ASCII platforms, but
since ordinal 127 is a not a control character on EBCDIC machines,
C<\c?> instead maps on them to C<APC>, which is 255 in 0037 and 1047,
and 95 in POSIX-BC.

=head1 FUNCTION DIFFERENCES

=over 8

=item C<chr()>

C<chr()> must be given an EBCDIC code number argument to yield a desired
character return value on an EBCDIC platform.  For example:

    $CAPITAL_LETTER_A = chr(193);

The largest code point that is representable in UTF-EBCDIC is
U+7FFF_FFFF.  If you do C<chr()> on a larger value, a runtime error
(similar to division by 0) will happen.

=item C<ord()>

C<ord()> will return EBCDIC code number values on an EBCDIC platform.
For example:

    $the_number_193 = ord("A");

=item C<pack()>


The C<"c"> and C<"C"> templates for C<pack()> are dependent upon character set
encoding.  Examples of usage on EBCDIC include:

    $foo = pack("CCCC",193,194,195,196);
    # $foo eq "ABCD"
    $foo = pack("C4",193,194,195,196);
    # same thing

    $foo = pack("ccxxcc",193,194,195,196);
    # $foo eq "AB\0\0CD"

The C<"U"> template has been ported to mean "Unicode" on all platforms so
that

    pack("U", 65) eq 'A'

is true on all platforms.  If you want native code points for the low
256, use the C<"W"> template.  This means that the equivalences

    pack("W", ord($character)) eq $character
    unpack("W", $character) == ord $character

will hold.

The largest code point that is representable in UTF-EBCDIC is
U+7FFF_FFFF.  If you try to pack a larger value into a character, a
runtime error (similar to division by 0) will happen.

=item C<print()>

One must be careful with scalars and strings that are passed to
print that contain ASCII encodings.  One common place
for this to occur is in the output of the MIME type header for
CGI script writing.  For example, many Perl programming guides
recommend something similar to:

    print "Content-type:\ttext/html\015\012\015\012";
    # this may be wrong on EBCDIC

You can instead write

    print "Content-type:\ttext/html\r\n\r\n"; # OK for DGW et al

and have it work portably.

That is because the translation from EBCDIC to ASCII is done
by the web server in this case.  Consult your web server's documentation for
further details.

=item C<printf()>

The formats that can convert characters to numbers and vice versa
will be different from their ASCII counterparts when executed
on an EBCDIC platform.  Examples include:

    printf("%c%c%c",193,194,195);  # prints ABC

=item C<sort()>

EBCDIC sort results may differ from ASCII sort results especially for
mixed case strings.  This is discussed in more detail L<below|/SORTING>.

=item C<sprintf()>

See the discussion of C<L</printf()>> above.  An example of the use
of sprintf would be:

    $CAPITAL_LETTER_A = sprintf("%c",193);

=item C<unpack()>

See the discussion of C<L</pack()>> above.

=back

Note that it is possible to write portable code for these by specifying
things in Unicode numbers, and using a conversion function:

    printf("%c",utf8::unicode_to_native(65));  # prints A on all
                                               # platforms
    print utf8::native_to_unicode(ord("A"));   # Likewise, prints 65

See L<perluniintro/Unicode and EBCDIC> and L</CONVERSIONS>
for other options.

=head1 REGULAR EXPRESSION DIFFERENCES

You can write your regular expressions just like someone on an ASCII
platform would do.  But keep in mind that using octal or hex notation to
specify a particular code point will give you the character that the
EBCDIC code page natively maps to it.   (This is also true of all
double-quoted strings.)  If you want to write portably, just use the
C<\N{U+...}> notation everywhere where you would have used C<\x{...}>,
and don't use octal notation at all.

Starting in Perl v5.22, this applies to ranges in bracketed character
classes.  If you say, for example, C<qr/[\N{U+20}-\N{U+7F}]/>, it means
the characters C<\N{U+20}>, C<\N{U+21}>, ..., C<\N{U+7F}>.  This range
is all the printable characters that the ASCII character set contains.

Prior to v5.22, you couldn't specify any ranges portably, except
(starting in Perl v5.5.3) all subsets of the C<[A-Z]> and C<[a-z]>
ranges are specially coded to not pick up gap characters.  For example,
characters such as "E<ocirc>" (C<o WITH CIRCUMFLEX>) that lie between
"I" and "J" would not be matched by the regular expression range
C</[H-K]/>.  But if either of the range end points is explicitly numeric
(and neither is specified by C<\N{U+...}>), the gap characters are
matched:

    /[\x89-\x91]/

will match C<\x8e>, even though C<\x89> is "i" and C<\x91 > is "j",
and C<\x8e> is a gap character, from the alphabetic viewpoint.

Another construct to be wary of is the inappropriate use of hex (unless
you use C<\N{U+...}>) or
octal constants in regular expressions.  Consider the following
set of subs:

    sub is_c0 {
        my $char = substr(shift,0,1);
        $char =~ /[\000-\037]/;
    }

    sub is_print_ascii {
        my $char = substr(shift,0,1);
        $char =~ /[\040-\176]/;
    }

    sub is_delete {
        my $char = substr(shift,0,1);
        $char eq "\177";
    }

    sub is_c1 {
        my $char = substr(shift,0,1);
        $char =~ /[\200-\237]/;
    }

    sub is_latin_1 {    # But not ASCII; not C1
        my $char = substr(shift,0,1);
        $char =~ /[\240-\377]/;
    }

These are valid only on ASCII platforms.  Starting in Perl v5.22, simply
changing the octal constants to equivalent C<\N{U+...}> values makes
them portable:

    sub is_c0 {
        my $char = substr(shift,0,1);
        $char =~ /[\N{U+00}-\N{U+1F}]/;
    }

    sub is_print_ascii {
        my $char = substr(shift,0,1);
        $char =~ /[\N{U+20}-\N{U+7E}]/;
    }

    sub is_delete {
        my $char = substr(shift,0,1);
        $char eq "\N{U+7F}";
    }

    sub is_c1 {
        my $char = substr(shift,0,1);
        $char =~ /[\N{U+80}-\N{U+9F}]/;
    }

    sub is_latin_1 {    # But not ASCII; not C1
        my $char = substr(shift,0,1);
        $char =~ /[\N{U+A0}-\N{U+FF}]/;
    }

And here are some alternative portable ways to write them:

    sub Is_c0 {
        my $char = substr(shift,0,1);
        return $char =~ /[[:cntrl:]]/a && ! Is_delete($char);

        # Alternatively:
        # return $char =~ /[[:cntrl:]]/
        #        && $char =~ /[[:ascii:]]/
        #        && ! Is_delete($char);
    }

    sub Is_print_ascii {
        my $char = substr(shift,0,1);

        return $char =~ /[[:print:]]/a;

        # Alternatively:
        # return $char =~ /[[:print:]]/ && $char =~ /[[:ascii:]]/;

        # Or
        # return $char
        #      =~ /[ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/;
    }

    sub Is_delete {
        my $char = substr(shift,0,1);
        return utf8::native_to_unicode(ord $char) == 0x7F;
    }

    sub Is_c1 {
        use feature 'unicode_strings';
        my $char = substr(shift,0,1);
        return $char =~ /[[:cntrl:]]/ && $char !~ /[[:ascii:]]/;
    }

    sub Is_latin_1 {    # But not ASCII; not C1
        use feature 'unicode_strings';
        my $char = substr(shift,0,1);
        return ord($char) < 256
               && $char !~ /[[:ascii:]]/
               && $char !~ /[[:cntrl:]]/;
    }

Another way to write C<Is_latin_1()> would be
to use the characters in the range explicitly:

    sub Is_latin_1 {
        my $char = substr(shift,0,1);
        $char =~ /[ ¡¢£¤¥¦§¨©ª«¬­®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏ]
                  [ÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ]/x;
    }

Although that form may run into trouble in network transit (due to the
presence of 8 bit characters) or on non ISO-Latin character sets.  But
it does allow C<Is_c1> to be rewritten so it works on Perls that don't
have C<'unicode_strings'> (earlier than v5.14):

    sub Is_latin_1 {    # But not ASCII; not C1
        my $char = substr(shift,0,1);
        return ord($char) < 256
               && $char !~ /[[:ascii:]]/
               && ! Is_latin1($char);
    }

=head1 SOCKETS

Most socket programming assumes ASCII character encodings in network
byte order.  Exceptions can include CGI script writing under a
host web server where the server may take care of translation for you.
Most host web servers convert EBCDIC data to ISO-8859-1 or Unicode on
output.

=head1 SORTING

One big difference between ASCII-based character sets and EBCDIC ones
are the relative positions of the characters when sorted in native
order.  Of most concern are the upper- and lowercase letters, the
digits, and the underscore (C<"_">).  On ASCII platforms the native sort
order has the digits come before the uppercase letters which come before
the underscore which comes before the lowercase letters.  On EBCDIC, the
underscore comes first, then the lowercase letters, then the uppercase
ones, and the digits last.  If sorted on an ASCII-based platform, the
two-letter abbreviation for a physician comes before the two letter
abbreviation for drive; that is:

 @sorted = sort(qw(Dr. dr.));  # @sorted holds ('Dr.','dr.') on ASCII,
                                  # but ('dr.','Dr.') on EBCDIC

The property of lowercase before uppercase letters in EBCDIC is
even carried to the Latin 1 EBCDIC pages such as 0037 and 1047.
An example would be that "E<Euml>" (C<E WITH DIAERESIS>, 203) comes
before "E<euml>" (C<e WITH DIAERESIS>, 235) on an ASCII platform, but
the latter (83) comes before the former (115) on an EBCDIC platform.
(Astute readers will note that the uppercase version of "E<szlig>"
C<SMALL LETTER SHARP S> is simply "SS" and that the upper case versions
of "E<yuml>" (small C<y WITH DIAERESIS>) and "E<micro>" (C<MICRO SIGN>)
are not in the 0..255 range but are in Unicode, in a Unicode enabled
Perl).

The sort order will cause differences between results obtained on
ASCII platforms versus EBCDIC platforms.  What follows are some suggestions
on how to deal with these differences.

=head2 Ignore ASCII vs. EBCDIC sort differences.

This is the least computationally expensive strategy.  It may require
some user education.

=head2 Use a sort helper function

This is completely general, but the most computationally expensive
strategy.  Choose one or the other character set and transform to that
for every sort comparision.  Here's a complete example that transforms
to ASCII sort order:

 sub native_to_uni($) {
    my $string = shift;

    # Saves time on an ASCII platform
    return $string if ord 'A' ==  65;

    my $output = "";
    for my $i (0 .. length($string) - 1) {
        $output
           .= chr(utf8::native_to_unicode(ord(substr($string, $i, 1))));
    }

    # Preserve utf8ness of input onto the output, even if it didn't need
    # to be utf8
    utf8::upgrade($output) if utf8::is_utf8($string);

    return $output;
 }

 sub ascii_order {   # Sort helper
    return native_to_uni($a) cmp native_to_uni($b);
 }

 sort ascii_order @list;

=head2 MONO CASE then sort data (for non-digits, non-underscore)

If you don't care about where digits and underscore sort to, you can do
something like this

 sub case_insensitive_order {   # Sort helper
    return lc($a) cmp lc($b)
 }

 sort case_insensitive_order @list;

If performance is an issue, and you don't care if the output is in the
same case as the input, Use C<tr///> to transform to the case most
employed within the data.  If the data are primarily UPPERCASE
non-Latin1, then apply C<tr/[a-z]/[A-Z]/>, and then C<sort()>.  If the
data are primarily lowercase non Latin1 then apply C<tr/[A-Z]/[a-z]/>
before sorting.  If the data are primarily UPPERCASE and include Latin-1
characters then apply:

   tr/[a-z]/[A-Z]/;
   tr/[àáâãäåæçèéêëìíîïðñòóôõöøùúûüýþ]/[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞ/;
   s/ß/SS/g;

then C<sort()>.  If you have a choice, it's better to lowercase things
to avoid the problems of the two Latin-1 characters whose uppercase is
outside Latin-1: "E<yuml>" (small C<y WITH DIAERESIS>) and "E<micro>"
(C<MICRO SIGN>).  If you do need to upppercase, you can; with a
Unicode-enabled Perl, do:

    tr/ÿ/\x{178}/;
    tr/µ/\x{39C}/;

=head2 Perform sorting on one type of platform only.

This strategy can employ a network connection.  As such
it would be computationally expensive.

=head1 TRANSFORMATION FORMATS

There are a variety of ways of transforming data with an intra character set
mapping that serve a variety of purposes.  Sorting was discussed in the
previous section and a few of the other more popular mapping techniques are
discussed next.

=head2 URL decoding and encoding

Note that some URLs have hexadecimal ASCII code points in them in an
attempt to overcome character or protocol limitation issues.  For example
the tilde character is not on every keyboard hence a URL of the form:

    http://www.pvhp.com/~pvhp/

may also be expressed as either of:

    http://www.pvhp.com/%7Epvhp/

    http://www.pvhp.com/%7epvhp/

where 7E is the hexadecimal ASCII code point for "~".  Here is an example
of decoding such a URL in any EBCDIC code page:

    $url = 'http://www.pvhp.com/%7Epvhp/';
    $url =~ s/%([0-9a-fA-F]{2})/
              pack("c",utf8::unicode_to_native(hex($1)))/xge;

Conversely, here is a partial solution for the task of encoding such
a URL in any EBCDIC code page:

    $url = 'http://www.pvhp.com/~pvhp/';
    # The following regular expression does not address the
    # mappings for: ('.' => '%2E', '/' => '%2F', ':' => '%3A')
    $url =~ s/([\t "#%&\(\),;<=>\?\@\[\\\]^`{|}~])/
               sprintf("%%%02X",utf8::native_to_unicode(ord($1)))/xge;

where a more complete solution would split the URL into components
and apply a full s/// substitution only to the appropriate parts.

=head2 uu encoding and decoding

The C<u> template to C<pack()> or C<unpack()> will render EBCDIC data in
EBCDIC characters equivalent to their ASCII counterparts.  For example,
the following will print "Yes indeed\n" on either an ASCII or EBCDIC
computer:

    $all_byte_chrs = '';
    for (0..255) { $all_byte_chrs .= chr($_); }
    $uuencode_byte_chrs = pack('u', $all_byte_chrs);
    ($uu = <<'ENDOFHEREDOC') =~ s/^\s*//gm;
    M``$"`P0%!@<("0H+#`T.#Q`1$A,4%187&!D:&QP='A\@(2(C)"4F)R@I*BLL
    M+2XO,#$R,S0U-C<X.3H[/#T^/T!!0D-$149'2$E*2TQ-3D]045)35%565UA9
    M6EM<75Y?8&%B8V1E9F=H:6IK;&UN;W!Q<G-T=79W>'EZ>WQ]?G^`@8*#A(6&
    MAXB)BHN,C8Z/D)&2DY25EI>8F9J;G)V>GZ"AHJ.DI::GJ*FJJZRMKJ^PL;*S
    MM+6VM[BYNKN\O;Z_P,'"P\3%QL?(R<K+S,W.S]#1TM/4U=;7V-G:V]S=WM_@
    ?X>+CY.7FY^CIZNOL[>[O\/'R\_3U]O?X^?K[_/W^_P``
    ENDOFHEREDOC
    if ($uuencode_byte_chrs eq $uu) {
        print "Yes ";
    }
    $uudecode_byte_chrs = unpack('u', $uuencode_byte_chrs);
    if ($uudecode_byte_chrs eq $all_byte_chrs) {
        print "indeed\n";
    }

Here is a very spartan uudecoder that will work on EBCDIC:

    #!/usr/local/bin/perl
    $_ = <> until ($mode,$file) = /^begin\s*(\d*)\s*(\S*)/;
    open(OUT, "> $file") if $file ne "";
    while(<>) {
        last if /^end/;
        next if /[a-z]/;
        next unless int((((utf8::native_to_unicode(ord()) - 32 ) & 077)
                                                               + 2) / 3)
                    == int(length() / 4);
        print OUT unpack("u", $_);
    }
    close(OUT);
    chmod oct($mode), $file;


=head2 Quoted-Printable encoding and decoding

On ASCII-encoded platforms it is possible to strip characters outside of
the printable set using:

    # This QP encoder works on ASCII only
    $qp_string =~ s/([=\x00-\x1F\x80-\xFF])/
                    sprintf("=%02X",ord($1))/xge;

Starting in Perl v5.22, this is trivially changeable to work portably on
both ASCII and EBCDIC platforms.

    # This QP encoder works on both ASCII and EBCDIC
    $qp_string =~ s/([=\N{U+00}-\N{U+1F}\N{U+80}-\N{U+FF}])/
                    sprintf("=%02X",ord($1))/xge;

For earlier Perls, a QP encoder that works on both ASCII and EBCDIC
platforms would look somewhat like the following:

    $delete = utf8::unicode_to_native(ord("\x7F"));
    $qp_string =~
      s/([^[:print:]$delete])/
         sprintf("=%02X",utf8::native_to_unicode(ord($1)))/xage;

(although in production code the substitutions might be done
in the EBCDIC branch with the function call and separately in the
ASCII branch without the expense of the identity map; in Perl v5.22, the
identity map is optimized out so there is no expense, but the
alternative above is simpler and is also available in v5.22).

Such QP strings can be decoded with:

    # This QP decoder is limited to ASCII only
    $string =~ s/=([[:xdigit:][[:xdigit:])/chr hex $1/ge;
    $string =~ s/=[\n\r]+$//;

Whereas a QP decoder that works on both ASCII and EBCDIC platforms
would look somewhat like the following:

    $string =~ s/=([[:xdigit:][:xdigit:]])/
                                chr utf8::native_to_unicode(hex $1)/xge;
    $string =~ s/=[\n\r]+$//;

=head2 Caesarean ciphers

The practice of shifting an alphabet one or more characters for encipherment
dates back thousands of years and was explicitly detailed by Gaius Julius
Caesar in his B<Gallic Wars> text.  A single alphabet shift is sometimes
referred to as a rotation and the shift amount is given as a number $n after
the string 'rot' or "rot$n".  Rot0 and rot26 would designate identity maps
on the 26-letter English version of the Latin alphabet.  Rot13 has the
interesting property that alternate subsequent invocations are identity maps
(thus rot13 is its own non-trivial inverse in the group of 26 alphabet
rotations).  Hence the following is a rot13 encoder and decoder that will
work on ASCII and EBCDIC platforms:

    #!/usr/local/bin/perl

    while(<>){
        tr/n-za-mN-ZA-M/a-zA-Z/;
        print;
    }

In one-liner form:

    perl -ne 'tr/n-za-mN-ZA-M/a-zA-Z/;print'


=head1 Hashing order and checksums

Perl deliberately randomizes hash order for security purposes on both
ASCII and EBCDIC platforms.

EBCDIC checksums will differ for the same file translated into ASCII
and vice versa.

=head1 I18N AND L10N

Internationalization (I18N) and localization (L10N) are supported at least
in principle even on EBCDIC platforms.  The details are system-dependent
and discussed under the L<OS ISSUES> section below.

=head1 MULTI-OCTET CHARACTER SETS

Perl works with UTF-EBCDIC, a multi-byte encoding.  In Perls earlier
than v5.22, there may be various bugs in this regard.

Legacy multi byte EBCDIC code pages XXX.

=head1 OS ISSUES

There may be a few system-dependent issues
of concern to EBCDIC Perl programmers.

=head2 OS/400

=over 8

=item PASE

The PASE environment is a runtime environment for OS/400 that can run
executables built for PowerPC AIX in OS/400; see L<perlos400>.  PASE
is ASCII-based, not EBCDIC-based as the ILE.

=item IFS access

XXX.

=back

=head2 OS/390, z/OS

Perl runs under Unix Systems Services or USS.

=over 8

=item C<sigaction>

C<SA_SIGINFO> can have segmentation faults.

=item C<chcp>

B<chcp> is supported as a shell utility for displaying and changing
one's code page.  See also L<chcp(1)>.

=item dataset access

For sequential data set access try:

    my @ds_records = `cat //DSNAME`;

or:

    my @ds_records = `cat //'HLQ.DSNAME'`;

See also the OS390::Stdio module on CPAN.

=item C<iconv>

B<iconv> is supported as both a shell utility and a C RTL routine.
See also the L<iconv(1)> and L<iconv(3)> manual pages.

=item locales

Locales are supported.  There may be glitches when a locale is another
EBCDIC code page which has some of the
L<code-page variant characters|/The 13 variant characters> in other
positions.

There aren't currently any real UTF-8 locales, even though some locale
names contain the string "UTF-8".

See L<perllocale> for information on locales.  The L10N files
are in F</usr/nls/locale>.  C<$Config{d_setlocale}> is C<'define'> on
OS/390 or z/OS.

=back

=head2 POSIX-BC?

XXX.

=head1 BUGS

=over 4

=item *

The C<cmp> (and hence C<sort>) operators do not necessarily give the
correct results when both operands are UTF-EBCDIC encoded strings and
there is a mixture of ASCII and/or control characters, along with other
characters.

=item *

Ranges containing C<\N{...}> in the C<tr///> (and C<y///>)
transliteration operators are treated differently than the equivalent
ranges in regular expression patterns.  They should, but don't, cause
the values in the ranges to all be treated as Unicode code points, and
not native ones.  (L<perlre/Version 8 Regular Expressions> gives
details as to how it should work.)

=item *

Not all shells will allow multiple C<-e> string arguments to perl to
be concatenated together properly as recipes in this document
0, 2, 4, 5, and 6 might
seem to imply.

=item *

There are some bugs in the C<pack>/C<unpack> C<"U0"> template

=item *

There are a significant number of test failures in the CPAN modules
shipped with Perl v5.22.  These are only in modules not primarily
maintained by Perl 5 porters.  Some of these are failures in the tests
only: they don't realize that it is proper to get different results on
EBCDIC platforms.  And some of the failures are real bugs.  If you
compile and do a C<make test> on Perl, all tests on the C</cpan>
directory are skipped.

In particular, the extensions L<Unicode::Collate> and
L<Unicode::Normalize> are not supported under EBCDIC; likewise for the
(now deprecated) L<encoding> pragma.

L<Encode> partially works.

=item *

In earlier versions, when byte and character data were concatenated,
the new string was sometimes created by
decoding the byte strings as I<ISO 8859-1 (Latin-1)>, even if the
old Unicode string used EBCDIC.

=back

=head1 SEE ALSO

L<perllocale>, L<perlfunc>, L<perlunicode>, L<utf8>.

=head1 REFERENCES

L<http://anubis.dkuug.dk/i18n/charmaps>

L<http://www.unicode.org/>

L<http://www.unicode.org/unicode/reports/tr16/>

L<http://www.wps.com/projects/codes/>
B<ASCII: American Standard Code for Information Infiltration> Tom Jennings,
September 1999.

B<The Unicode Standard, Version 3.0> The Unicode Consortium, Lisa Moore ed.,
ISBN 0-201-61633-5, Addison Wesley Developers Press, February 2000.

B<CDRA: IBM - Character Data Representation Architecture -
Reference and Registry>, IBM SC09-2190-00, December 1996.

"Demystifying Character Sets", Andrea Vine, Multilingual Computing
& Technology, B<#26 Vol. 10 Issue 4>, August/September 1999;
ISSN 1523-0309; Multilingual Computing Inc. Sandpoint ID, USA.

B<Codes, Ciphers, and Other Cryptic and Clandestine Communication>
Fred B. Wrixon, ISBN 1-57912-040-7, Black Dog & Leventhal Publishers,
1998.

L<http://www.bobbemer.com/P-BIT.HTM>
B<IBM - EBCDIC and the P-bit; The biggest Computer Goof Ever> Robert Bemer.

=head1 HISTORY

15 April 2001: added UTF-8 and UTF-EBCDIC to main table, pvhp.

=head1 AUTHOR

Peter Prymmer pvhp@best.com wrote this in 1999 and 2000
with CCSID 0819 and 0037 help from Chris Leach and
AndrE<eacute> Pirard A.Pirard@ulg.ac.be as well as POSIX-BC
help from Thomas Dorner Thomas.Dorner@start.de.
Thanks also to Vickie Cooper, Philip Newton, William Raffloer, and
Joe Smith.  Trademarks, registered trademarks, service marks and
registered service marks used in this document are the property of
their respective owners.

Now maintained by Perl5 Porters.