Next: GUI program problems, Previous: Advanced gettext functions, Up: Message catalogs with gettext
gettext usesgettext not only looks up a translation in a message catalog. It
also converts the translation on the fly to the desired output character
set. This is useful if the user is working in a different character set
than the translator who created the message catalog, because it avoids
distributing variants of message catalogs which differ only in the
character set.
The output character set is, by default, the value of nl_langinfo
(CODESET), which depends on the LC_CTYPE part of the current
locale. But programs which store strings in a locale independent way
(e.g. UTF-8) can request that gettext and related functions
return the translations in that encoding, by use of the
bind_textdomain_codeset function.
Note that the msgid argument to gettext is not subject to
character set conversion. Also, when gettext does not find a
translation for msgid, it returns msgid unchanged –
independently of the current output character set. It is therefore
recommended that all msgids be US-ASCII strings.
The
bind_textdomain_codesetfunction can be used to specify the output character set for message catalogs for domain domainname. The codeset argument must be a valid codeset name which can be used for theiconv_openfunction, or a null pointer.If the codeset parameter is the null pointer,
bind_textdomain_codesetreturns the currently selected codeset for the domain with the name domainname. It returnsNULLif no codeset has yet been selected.The
bind_textdomain_codesetfunction can be used several times. If used multiple times with the same domainname argument, the later call overrides the settings made by the earlier one.The
bind_textdomain_codesetfunction returns a pointer to a string containing the name of the selected codeset. The string is allocated internally in the function and must not be changed by the user. If the system went out of core during the execution ofbind_textdomain_codeset, the return value isNULLand the global variable errno is set accordingly.