GETTEXT(3)

NAME
gettext, dgettext, ngettext, dngettext, textdomain, bindtextdomain, bind_textdomain_codeset, dcgettext, dcngettext - message handling functions

LIBRARY
libintl

SYNOPSIS
#include <libintl.h>
char *
gettext(const char *msgid);
char *
dgettext(const char *domainname, const char *msgid);
char *
ngettext(const char *msgid1, const char *msgid2, unsigned long int n);
char *
dngettext(const char *domainname, const char *msgid1, const char *msgid2, unsigned long int n);
char *
textdomain(const char *domainname);
char *
bindtextdomain(const char *domainname, const char *dirname);
char *
bind_textdomain_codeset(const char *domainname, const char *codeset);
#include <libintl.h>
#include <locale.h>
char *
dcgettext(const char *domainname, const char *msgid, int category);
char *
dcngettext(const char *domainname, const char *msgid1, const char *msgid2, unsigned long int n, int category);

DESCRIPTION
The gettext(), dgettext(), and dcgettext() functions attempt to retrieve a target string based on the specified msgid argument within the context of a specific domain and the current locale. The length of strings returned by gettext(), dgettext(), and dcgettext() is undetermined until the function is called. The msgid argument is a nul-terminated string.

The ngettext(), dngettext(), and dcngettext() functions are equivalent to gettext(), dgettext(), and dcgettext(), respectively, except for the handling of plural forms. The ngettext(), dngettext(), and dcngettext() functions search for the message string using the msgid1 argument as the key, using the argument n to determine the plural form. If no message catalogs are found, msgid1 is returned if n == 1, otherwise msgid2 is returned.

The LANGUAGE environment variable is examined first to determine the message catalogs to be used. The value of the LANGUAGE environment variable is a list of locale names separated by colon (:) character. If the LANGUAGE environment variable is defined, each locale name is tried in the specified order and if a message catalog containing the requested message is found, the message is returned. If the LANGUAGE environment variable is defined but failed to locate a message catalog, the msgid string will be returned.

If the LANGUAGE environment variable is not defined, LC_ALL, LC_xxx, and LANG environment variables are examined to locate the message catalog, following the convention used by the setlocale(3) function.

The pathname used to locate the message catalog is dirname/locale/category/domainname.mo, where dirname is the directory specified by bindtextdomain(), locale is a locale name determined by the definition of environment variables, category is LC_MESSAGES if gettext(), ngettext(), dgettext(), or dngettext() is called, otherwise LC_xxx where the name is the same as the locale category name specified by the category argument of dcgettext() or dcngettext(). domainname is the name of the domain specified by textdomain() or the domainname argument of dgettext(), dngettext(), dcgettext(), or dcngettext().

For gettext() and ngettext(), the domain used is set by the last valid call to textdomain(). If a valid call to textdomain() has not been made, the default domain (called messages) is used.

For dgettext(), dngettext(), dcgettext(), and dcngettext(), the domain used is specified by the domainname argument. The domainname argument is equivalent in syntax and meaning to the domainname argument to textdomain(), except that the selection of the domain is valid only for the duration of the dgettext(), dngettext(), dcgettext(), or dcngettext() function call.

The dcgettext() and dcngettext() functions require additional argument category for retrieving message string for other than LC_MESSAGES category. Available value for the category argument are LC_CTYPE, LC_COLLATE, LC_MESSAGES, LC_MONETARY, LC_NUMERIC, and LC_TIME. The call of dcgettext(domainname, msgid, LC_MESSAGES) is equivalent to dgettext(domainname, msgid). Note that LC_ALL must not be used.

The textdomain() function sets or queries the name of the current domain of the active LC_MESSAGES locale category. The domainname argument is a nul-terminated string that can contain only the characters allowed in legal filenames.

The domainname argument is the unique name of a domain on the system. If there are multiple versions of the same domain on one system, namespace collisions can be avoided by using bindtextdomain(). If textdomain() is not called, a default domain is selected. The setting of domain made by the last valid call to textdomain() remains valid across subsequent calls to setlocale(3), and gettext().

The domainname argument is applied to the currently active LC_MESSAGES locale.

The current setting of the domain can be queried without affecting the current state of the domain by calling textdomain() with domainname set to the NULL pointer. Calling textdomain() with a domainname argument of a NULL string sets the domain to the default domain (messages).

The bindtextdomain() function binds the path predicate for a message domain domainname to the value contained in dirname. If domainname is a non-empty string and has not been bound previously, bindtextdomain() binds domainname with dirname.

If domainname is a non-empty string and has been bound previously, bindtextdomain() replaces the old binding with dirname. The dirname argument can be an absolute pathname being resolved when gettext(), ngettext(), dgettext(), dngettext(), dcgettext(), or dcngettext() are called. If domainname is a NULL pointer or an empty string, bindtextdomain() returns a NULL pointer. If bindtextdomain() is not called, implementation-defined default directory is used.

The bind_textdomain_codeset() function can be used to specify the output codeset for message catalogs for domain domainname. The codeset argument must be a valid codeset name which can be used for the iconv_open(3) function.

If the codeset argument is the NULL pointer, bind_textdomain_codeset() returns the currently selected codeset for the domain with the name domainname. It returns a NULL pointer if no codeset has yet been selected.

The bind_textdomain_codeset() function 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_codeset() function returns a pointer to a string containing the name of the selected codeset.

SEE ALSO
setlocale(3), nls(7)

HISTORY
The functions are implemented by Citrus project, based on the documentations for GNU gettext.

BUGS
bind_textdomain_codeset() does not work at this moment (it always fails).