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.
gv2gml version (return code: 0)
Can't open version
gv2gml --help (return code: 1)
gv2gml: option -- unrecognized
Usage: gv2gml [-?] <files>
-o<file> : output to <file> (stdout)
-? - print usage
If no files are specified, stdin is used