Re: [libvirt] [PATCH] virsh: don't shorten incorrect arguments

On 04/23/2013 06:05 PM, Eric Blake wrote: > On 04/23/2013 08:08 AM, Ján Tomko wrote: >> https://bugzilla.redhat.com/show_bug.cgi?id=949373 >> >> Print the whole incorrect argument as specified by the user >> instead of the short option. >> > >> case 'd': >> if (virStrToLong_i(optarg, NULL, 10, &debug) < 0) { >> - vshError(ctl, "%s", _("option -d takes a numeric argument")); >> + vshError(ctl, _("option %s takes a numeric argument"), argv[optind - 2]); > > I'm not sure this gives the nicest output. With short option bundling, > this results in > > $ tools/virsh -rd > error: option '-rd' requires an argument > > even though the -r option was just fine, and it is really just the > bundled '-d' option that has a problem. The output is even worse with two unrecognized options: $ tools/virsh -pm error: unsupported option '.../tools/.libs/virsh'. See --help.

> > Also, I wonder if we should be using a non-NULL 5th parameter to > getopt_long; if you provide a longindex parameter, then you can provide > a nicer error message that mentions the full "--debug" name (rather than > the user-typed abbreviation '--debu') by indexing back into the > long-option table (of course, do this only when it was a long option > that was misused). It seems longindex is only set when the option parsing is successful. If we removed the ':' from optstring and let getopt handle the errors, it would correctly translate --deb to --debug, but keep the short options unchanged: $ tools/virsh --deb .../virsh: option '--debug' requires an argument ... $ tools/virsh -rd .../virsh: option requires an argument -- 'd' ... Maybe we should revert commit dd71fa1 ([1]) and change the message to something more generic, for example: error: See virsh --help.