[Toybox] sntp -m design/documentation (optional arguments help syntax?)

[enh]

isn't this [-m [ADDRESS]]?

http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap12.html#tag_12_01

On Tue, Feb 5, 2019 at 5:59 AM Rob Landley <rob at landley.net> wrote:
>
> RFC 4330 (and newer) say that the default multicast address for broadcast sntp
> time updates is 224.0.1.1 so I want "sntp -m" to have an optional argument
> overriding that, but otherwise take the default.
>
> Unfortunately, "optional aguments" exist but aren't used much. For example
> --color is technically --color=auto (and can also take --color=always and
> --color=never)... but actualy looking at what's after the = is still a todo item
> for ls. (I think I might have done it in grep? I'd have to check. I _do_ have a
> note that I should try to factor out common code there into lib...)
>
> For optional longopts, you have to go =argument, for optional short options you
> have to collate, in this case it would look like:
>
>   sntp -m224.0.1.1
>
> If you have a space it instead thinks you're going "sntp 224.0.1.1 -m", because
> that's how optional arguments work. (And yes this means you can sntp -sM but not
> sntp -Ms .)
>
> The _problem_ is, even though I have this mechanism... I have no idea how to
> usefully describe in the help text so users know what to do? I don't really have
> a "usage: blah [-abc] ARG..." syntax for it, and even if I did it's not in
> widespread enough use I'd expect people to pick it up? I added a "[-mADDRESS]"
> entry to the command line but it's too subtle...
>
> Not sure what to do about that. For the moment, I guess -m requires the
> argument? (Yes, somebody is still using multicast for something. In 2019. I
> know, but there's a user waiting...)
>
> Trying to cut a release and promoting sntp is the most prominent remaining todo
> item...
>
> Rob
> _______________________________________________
> Toybox mailing list
> Toybox at lists.landley.net
> http://lists.landley.net/listinfo.cgi/toybox-landley.net