[Toybox] xxd -ps

[Rob Landley]

On 11/15/18 6:38 PM, enh wrote:
> so xxd has some weird cancers, and i've been ignoring them, and have
> uploaded https://android-review.googlesource.com/c/platform/build/+/828285
> to AOSP to stop using -ps, but i'm mildly curious...
> 
> given that xxd has a -p and a -s (which takes a numeric argument),
> what would we have to do to also accept -ps as a synonym for -p
> (rather than as -p plus -s but missing a numeric argument)? i'm
> assuming that would be awful and not worth it?

I... er...  what?

> from the xxd man page:
> 
>        -p | -ps | -postscript | -plain
>               output  in  postscript  continuous  hexdump style. Also known as
>               plain hexdump style.

That's... ouch.

Somebody pointed out a corner case where the "ps" command had some similar
insanity, but given that I haven't yet implemented the bsd-style options
(despite "ps ax" being hardwired into my muscle memory at this point) I flung
the note at the end of a todo list I can't currently find. (I think I had a
window open with it on the netbook that died.)

> is there a way to say "this bizarre command's longopts actually use a
> single -"? are there any commands other than xxd that would even use
> this?

Yeah, gcc and kill both do that. I'm not implementing a compiler in toybox (if I
get a chance at qcc it's a separate project) and did kill another way.

Hmmm... I could add a lib/args.c optstring prefix character to tell it "check
for longopts before parsing each single dash option group"? That wouldn't be too
hard. That would still treat "-lps" as "-l -p -s" rather than "-l -ps" but
assuming that's what we want here...

Hmmm, should I keep it unique and use "`" or some such, or use "-" for this and
have that mean two different things when coming after an option vs when coming
before all options? (The code probably doesn't care but the users might.)

Rob

P.S. Projects accumulate complexity as they encounter more of the real world.
It's kind of annoying.