/usr/share/xfig/Libraries/DSP/mux.fig is in xfig-libs 1:3.2.5.c-7.
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 | #FIG 3.2
Landscape
Center
Inches
Letter
100.00
Single
-2
1200 2
6 4500 6000 4950 6900
6 4500 6000 4950 6900
2 2 0 1 0 7 50 0 -1 0.000 0 0 -1 0 0 5
4950 6900 4500 6900 4500 6000 4950 6000 4950 6900
2 1 0 1 0 7 50 0 -1 0.000 0 0 -1 0 0 2
4950 6450 4500 6900
2 1 0 1 0 7 50 0 -1 0.000 0 0 -1 0 0 2
4950 6450 4500 6000
-6
-6
|