On Wed, Nov 27, 2024 at 04:29:43PM +0200, Eli Zaretskii wrote: > > From: Gavin Smith <gavinsmith0...@gmail.com> > > Date: Tue, 26 Nov 2024 18:33:31 +0000 > > > > On the two systems you mention (Cygwin64 and Macos-13), in spite of > > Perl appearing to be new enough, calling gettext does not work. It > > is presumed that calling back into Perl would work, though. Have I > > understood the issue correctly? > > Can you please explain what you mean by "calling back into Perl"? > What kind of call is made from the C code of an XS, and what functions > in Perl does it call?
It is possible to call any Perl function from C code using the Perl C API and having a Perl interpreter available. It is described here: https://perldoc.perl.org/perlcall The precise code is in tp/Texinfo/XS/main/call_perl_function.c, function call_translations_translate_string. There is some code to setup the Perl stack, convert C to SV * Perl objects and push on the Perl stack: PUSHs(sv_2mortal (newSVpv_utf8 (string, 0))); PUSHs(sv_2mortal (newSVpv_utf8 (in_lang, 0))); PUSHs(sv_2mortal (newSVpv_utf8 (translation_context, 0))); the call to the Perl function: count = call_pv ( "Texinfo::Translations::translate_string", G_SCALAR); and getting the result from the return of the Perl function: result_sv = POPs; result_ret = SvPVutf8 (result_sv, len); > And also, do you have any guesses for why calling gettext from XS > doesn't work? My guess is that it is related to the switching of locale using calls to getenv and searching for an existing locale to use the @documentlanguage, as it has always been very fragile and prone to fail, both in pure Perl and in C. It could also fail because this local switching is done from C called from Perl, we had trouble with that previously and needed to call some Perl functions related to threads to make things work, while it worked well from C only. > XS is just C code, It is just C code, but as said above, it is possible to call Perl code from XS. > and gettext is callable from C, so > what could be the problem? There is something going on that makes the C code fail to find the translated strings, the workaround consist in calling the pure Perl libintl-perl Gettext implementation from C through the mechanism explained above to retrieve the translated string. So, we actually avoid calling the C gettext to get the output we want. I think that it would be better to investigate why calling C gettext from C code does not work, but it requires direct access to the platforms. -- Pat
