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 <[email protected]> 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 > [email protected] > http://lists.landley.net/listinfo.cgi/toybox-landley.net _______________________________________________ Toybox mailing list [email protected] http://lists.landley.net/listinfo.cgi/toybox-landley.net
