grog --version (return code: 0)
Perl version of GNU grog in groff version 1.22.3
grog --help (return code: 0)
usage: grog [option]... [--] [filespec]...
"filespec" is either the name of an existing, readable file or "-" for
standard input. If no `filespec' is specified, standard input is
assumed automatically. All arguments after a `--' are regarded as file
names, even if they start with a `-' character.
`option' is either a `groff' option or one of these:
-h|--help print this uasge message and exit
-v|--version print version information and exit
-C compatibility mode
--ligatures include options `-P-y -PU' for internal font, which
preserverses the ligatures like `fi'
--run run the checked-out groff command
--warnings display more warnings to standard error
All other options should be `groff' 1-character options. These are then
appended to the generated `groff' command line. The `-m' options will
be checked by `grog'.