Re: getopt() and POSIX

[Eli Zaretskii]

> From: Elad Lahav <e2lahav@gmail.com>
> Date: Tue, 16 May 2023 13:59:29 -0400
> 
> The configure script attempts to determines whether getopt() is POSIX
> compliant by compiling and running the following code:
> 
> #include <unistd.h>
> #include <stdlib.h>
> #include <string.h>
> 
> int
> main ()
> {
>   static char program[] = "program";
>   static char ab[] = "-ab";
>   char *argv[3] = { program, ab, NULL };
>   if (getopt (2, argv, "ab:") != 'a')
>     return 13;
>   if (getopt (2, argv, "ab:") != '?')
>     return 14;
>   if (optopt != 'b')
>     return 15;
>   if (optind != 2)
>     return 16;
>   return 0;
> }
> 
> This test fails on QNX for the last test point, which has optind set
> to 3. However, as far as I can tell, this is what POSIX expects, and 2
> is wrong:
> 
> https://pubs.opengroup.org/onlinepubs/9699919799/functions/getopt.html
> 
> "If the option was the last character in the string pointed to by an
> element of argv, then optarg shall contain the next element of argv,
> and optind shall be incremented by 2. If the resulting value of optind
> is greater than argc, this indicates a missing option-argument, and
> getopt() shall return an error indication."
> 
> In this case optind is 1 and incremented by 2, the argument is missing
> and now optind is greater than argc (2), as expected.
> 
> None of this really matters much, except that the compliance failure
> leads to an attempt to use rpl_getopt(), which fails due to unresolved
> symbols (which is a separate issue).

Both this test and rpl_getopt are imported from Gnulib, so please
report these 2 issues to bug-gnulib@gnu.org, so that Gnulib developers
could take care of what needs to be fixed.

Thanks.