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.
zerofree -V (return code: 1)
zerofree: invalid option -- '-'
usage: zerofree [-n] [-v] [-f fillval] filesystem
zerofree --help (return code: 1)
zerofree: invalid option -- '-'
usage: zerofree [-n] [-v] [-f fillval] filesystem