On Tue, Aug 17, 2010 at 08:07:05PM +0200, Alexander Teinum wrote: > > I think the best format for usage is something like what Plan 9 > > utilities use (BSD use the same): > > > > usage: cmd [-abcde] [-f file] [-g pattern] [file ...] > > Options without values are combined? Is that correct?
Yes. If you don't use getopt like most suckless projects then no. > > With these rules flo usage should be > > > > usage: flo [-c id] [-f from] [-r id] [-t to] [-w what] [what[,from][-to]] > > What if the values are of the same type? -c and -r have id as value. > -f and -t have date as value. I think your usage-text looks prettier, > but out of curiosity, can they be combined like this? > > usage: flo [-cr id] [-ft date] … Didn't see anything like that. Even when the types are same, options mean different things so they are listed like [-f from] [-t to]. crop utility from Plan 9 have two arguments that accept rgb colors and they are listed separately. > If I decide to ditch getopt(), then I’d like to be able to type “flo > -c -f” to clear the from-field, which means that -f and -t have > optional arguments. Is it valid for an option to have an optional > argument? No. If there is no argument but some option goes after it like flo -c -f -t then -t would become argument for -f. That way you always have to make sure that -f is the last argument or write parser that don't allow you to use -t as argument or something like this. Most unix utilities use getopt() so you can look at Plan 9 utilities for examples of man pages and usage. suckless.org utilities use their own simple parsers that don't allow you to group options with one '-' so they list their options like [-a] [-b] [-c]. If you write your own parser that allow optional arguments and strange things like this, then there can be no examples or guidelines. > I found some guidelines here: > > http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap12.html#tag_12_01c > > Do you agree with the guidelines listed in 12.2? I’ll find a pen and a > paper and try to digest those. Disagree with Guideline 6. awk can accept both -Farg and -F arg. I think all options should be listed like '[-o arg]' but accept both -oarg or '-o arg'. For ssuckless projects they should be listed like '[-o arg]' and accept only '-o arg' form. Guideline 8 is strange. crop utility from Plan 9 have options that get 3 arguments and it is ok. But with GNU getopt it would fail because it move 2nd and 3rd arguments to the end so they become non-option arguments. Guideline 9 is like BSD getopt work. GNU getopt allow you to put options after arguments but I don't like it. I wonder why glibc developers put arguments sorting in getopt. It would be much better to place it in bash and enable only when runned in interactive mode. I use mksh anyway :-p Guideline 13 should be deprecated. It is not compatible with Plan 9 cat and only leads to additional code complexity. Use /dev/stdin instead.
