gdb output of crash:
> Program received signal SIGPIPE, Broken pipe.
> 0x00007ffff7b08ae0 in __write_nocancel () from /lib64/libc.so.6
> (gdb) bt
> #0 0x00007ffff7b08ae0 in __write_nocancel () from /lib64/libc.so.6
> #1 0x000000000040132a in fork_after_grep (opts=...) at fag.c:190
> #2 0x0000000000400ea2 in main (argc=5, argv=0x7fffffffe128) at fag.c:83
if grep exits with an error, fag thinks, a match was found.
simulate by setting grep's arguments to "-GE" (conflicting regex types)
in the code (setting both from the cli won't trigger, as only the last
one will be passed thru to grep)
you can use grep options -E, -F, -G, -P, -i, -w, -x, -y, and -U now.
these are the only ones that make sense (to me at least) to include
besides -e (multiple patterns) and -f (patterns from file).