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.
mailq -version (return code: 0)
mailq: -e option ignored
Mail queue is empty
mailq (return code: 0)
Mail queue is empty