Re: POSIX msgfmt and duplicate msgids

[Bruno Haible]

Eric Blake wrote:
> In the msgfmt(1) utility, there is currently a difference between GNU
> and Illumos implementations on detecting duplicate msgid strings, and
> which command line switch(es) make detection of duplicates possible.
> The question is whether GNU msgfmt would be willing to use the current
> -c option (--check) have a mode for erroring out on duplicate msgid
> strings, or even adding a new command line option (-n appears to be
> available, for a mnemonic of 'no dupes') to have the duplicate
> detection available without requiring -c.

https://posix.rhansen.org/p/gettext_draft
Lines 925..926, 1140

"-n     Do not allow duplicate msgid directives. Treat duplicate msgid
        directives for the same message_identifier as errors instead of
        ignoring the duplicates."

This does not deserve a specific option. *Of course* an input file with
duplicate msgids is abnormal; this is like a C file that defines two
functions with the same name. And that implies that when invoked with
-c and -v, the 'msgfmt' program must produce an error.

None of the following has this '-n' option:
  - The LI18NUX 2000 specification
  - GNU msgfmt
    https://www.gnu.org/software/gettext/manual/html_node/msgfmt-Invocation.html
  - Solaris msgfmt
    https://docs.oracle.com/cd/E88353_01/html/E37839/msgfmt-1.html

When '-c' and '-v' are *not* specified, I don't care whether the standard
requires msgfmt to diagnose this abnormality of the input. But it should
definitely not prohibit it.

Suggestion:
Remove these lines.

> The question is whether GNU msgfmt would be willing to use the current
> -c option (--check) have a mode for erroring out on duplicate msgid
> strings

It doesn't need a mode for that. GNU msgfmt already errors out on
duplicate msgids, even without '-c'.

Bruno