Note: help and version output are generated by a naïve script which tries a few variants of
<command> --help, <command> -h etc. to find the command's help and version info.
Sometimes it gets lucky, sometimes it doesn't; if the output below looks wrong, it probably is.
wavfilter -V (return code: 1)
usage: wavfilter <lp | hp> <cutoff> <in.wav> <out.wav>
wavfilter --help (return code: 1)
usage: wavfilter <lp | hp> <cutoff> <in.wav> <out.wav>