Improving BSD licensed text-processing tools

[Jesse Hagewood]

A lot of progress was made this week on gzip support in diff and sdiff. I
included functions to also check for a .gz file extension, and I
implemented this in such a way to where it can compare a decompressed gzip
file to a regular file, and also decompress .gz files if regular diff is
ran, and the Makefiles for diff and sdiff both compile zdiff and zsdiff
binaries. The only issue I'm facing is a SIGBUS error and I'm using gdb to
try and detect the bug. Once the bugs are straightened out, I'm going to
write the man pages for zdiff and zsdiff, which shouldn't be too difficult
from what I learned about man/roff macros by studying mdocml.

I also need more thorough performance testing against the GNU utilities. So
far I've been using the time utility to test performance, but with the
inputs I'm using it only give me execution times of 0.00 seconds. I'm going
to use larger imput files, and also try to find another Unix utility for
this type of benchmarking if I can find a proper one.