is there a g_option_print_usage() command?

[Rick Jones <rick jones2 hp com>]

I see that goption can uatomagically handle --help and the like.  I'd 
like to emit a usage string when someone gives a bogus option - is there 
 a call one can make to just print the same stuff that goption does on 
its own with --help, or do I have to mess about with error hooks?

http://developer.gnome.org/doc/API/2.0/glib/glib-Commandline-option-parser.html
didn't mention one - before I use something I find from source I'd want 
to check that it was simply an oversight in the api docs :)

thanks,

rick jones