13 Mar
2020
13 Mar
'20
1:24 a.m.
John P. Linderman wrote in
<CAC0cEp_fQsq6-EaG-nhvXTvZij+PSab5PNTEx7WhNjYwnFVnaw(a)mail.gmail.com>:
|My error. I was looking at getopt(1) rather than getopt(3). Of course \
|optind is documented, it's the way to find non-flag arguments.
|I don't know why the Hancock authors chose to make rsort into a subroutine \
|rather than just piping into the command. Perhaps something to do with \
|the software release process?
I really like a lot of such old code, and reading it. One can
only learn from it. Even though i discovered all this in
(Free)BSD land, after coming over from Linux, I loved reading
those "old-hand" comment blocks, it was inspiration and kindled
something here. For the few pieces of code that i am prowd of aka
that i thought were worth it i followed their example. This
rsort.c is however more verbose and spiritful than anything i ever
wrote. I keep it in my box of precious things.
getopt(3) on the other hand is portable but terrible. Just on the
10th i resorted a small SCSI MMC-3 cdda access tool (~50 KB
C source are necessary for that in 2020, missing Solaris and
MacOS, but including CD-TEXT and all that!!) to it because people
are used to option and/or argument joining etc, but it lost long
option support.
Not worth commenting a lot, but here is an option parser of 6359
bytes when development verification code and dump_doc() are not
counted, but is uses a carrier struct, supports long options, and
documentation strings as part of long option strings (one .RODATA
entry). FreeBSD's standard compatible and thus naked
lib/libc/stdlib/getopt.c is 4312 bytes. And GNU's getopt_long is
huge and even permutates arguments.
At least getopt(3) is predictable once a user gets it. Things are
different for sed(1)s -i and some sccs commands i have forgotten.
I think it has even be tried to standardize optional arguments in
that respect, but i would argue this is not a good direction to
go, consider for example "sed -ie". Isn't this asking for
troubles without accompanying comments.
* static char const a_sopts[] = "A:h#";
* static char const * const a_lopts[] = {
* "account:;A;" N_("execute an `account' command"),
..
* "long-help;\201;" N_("this listing"),
* NIL
* };
..
* struct su_avopt avo;
..
* su_avopt_setup(&avo, --argc, C(char const*const*,++argv),
* a_sopts, a_lopts);
* while((i = su_avopt_parse(&avo)) != su_AVOPT_STATE_DONE){
* switch(i){
* case 'A':
* "account_name" = avo.avo_current_arg;
* break;
* case 'h':
* case S(char,S(u8,'\201')):
* a_main_usage(n_stdout);
* if(i != 'h'){
* fprintf(n_stdout, "\nLong options:\n");
* su_avopt_dump_doc(&avo, &a_main_dump_doc, S(up,n_stdout));
* }
* exit(0);
..
* argc = avo.avo_argc;
* argv = C(char**,avo.avo_argv);
--steffen
|
|Der Kragenbaer, The moon bear,
|der holt sich munter he cheerfully and one by one
|einen nach dem anderen runter wa.ks himself off
|(By Robert Gernhardt)