gettext(3C) Standard C Library Functions gettext(3C)NAME
gettext, dgettext, dcgettext, ngettext, dngettext, dcngettext, textdo‐
main, bindtextdomain, bind_textdomain_codeset - message handling func‐
tions
SYNOPSIS
Solaris and GNU-compatible
#include <libintl.h>
char *gettext(const char *msgid);
char *dgettext(const char *domainname, const char *msgid);
char *textdomain(const char *domainname);
char *bindtextdomain(const char *domainname, const char *dirname);
#include <libintl.h>
#include <locale.h>
char *dcgettext(const char *domainname, const char *msgid, int cate‐
gory);
GNU-compatible
#include <libintl.h>
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 *bind_textdomain_codeset(const char *domainname, const char *code‐
set);
#include <libintl.h>
#include <locale.h>
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 undeter‐
mined until the function is called. The msgid argument is a null-termi‐
nated string.
The ngettext(), dngettext(), and dcngettext() functions are equivalent
to gettext(), dgettext(), and dcgettext(), respectively, except for the
handling of plural forms. These functions work only with GNU-compati‐
ble message catalogues. The ngettext(), dngettext(), and dcngettext()
functions search for the message string using the msgid1 argument as
the key and the n argument to determine the plural form. If no message
catalogues are found, msgid1 is returned if n == 1, otherwise msgid2 is
returned.
The NLSPATH environment variable (see environ(5)) is searched first for
the location of the LC_MESSAGES catalogue. The setting of the LC_MES‐
SAGES category of the current locale determines the locale used by
gettext() and dgettext() for string retrieval. The category argument
determines the locale used by dcgettext(). If NLSPATH is not defined
and the current locale is "C", gettext(), dgettext(), and dcgettext()
simply return the message string that was passed. In a locale other
than "C", if NLSPATH is not defined or if a message catalogue is not
found in any of the components specified by NLSPATH, the routines
search for the message catalogue using the scheme described in the fol‐
lowing paragraph.
The LANGUAGE environment variable is examined to determine the GNU-com‐
patible message catalogues to be used. The value of LANGUAGE is a list
of locale names separated by a colon (':') character. If LANGUAGE is
defined, each locale name is tried in the specified order and if a GNU-
compatible message catalogue is found, the message is returned. If a
GNU-compatible message catalogue is found but failed to find a corre‐
sponding msgid, the msgid string is return. If LANGUAGE is not defined
or if a Solaris message catalogue is found or no GNU-compatible message
catalogue is found in processing LANGUAGE, the pathname used to locate
the message catalogue is dirname/locale/category/domainname.mo, where
dirname is the directory specified by bindtextdomain(), locale is a
locale name, and category is either LC_MESSAGES if gettext(), dget‐
text(), ngettext(), or dngettext() is called, or LC_XXX where the name
is the same as the locale category name specified by the category argu‐
ment to 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(), dcgettext(), dngettext(), 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(), dcgettext(), dngettext(), or dcnget‐
text() function call.
The textdomain() function sets or queries the name of the current
domain of the active LC_MESSAGES locale category. The domainname argu‐
ment is a null-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, names‐
pace collisions can be avoided by using bindtextdomain(). If textdo‐
main() 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(3C), 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 or relative pathname being resolved when
gettext(), dgettext(), or dcgettext() are called. If domainname is a
null pointer or an empty string, bindtextdomain() returns NULL. User
defined domain names cannot begin with the string SYS_. Domain names
beginning with this string are reserved for system use.
The bind_textdomain_codeset() function can be used to specify the out‐
put codeset for message catalogues for domain domainname. The codeset
argument must be a valid codeset name that can be used for the
iconv_open(3C) function, or a null pointer. 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 a codeset has not yet been selected. The bind_textdo‐
main_codeset() function can be used multiple 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() func‐
tion 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.
RETURN VALUES
The gettext(), dgettext(), and dcgettext() functions return the message
string if the search succeeds. Otherwise they return the msgid string.
The ngettext(), dngettext(), and dcngettext() functions return the mes‐
sage string if the search succeeds. If the search fails, msgid1 is
returned if n == 1. Otherwise msgid2 is returned.
The individual bytes of the string returned by gettext(), dgettext(),
dcgettext(), ngettext(), dngettext(), or dcngettext() can contain any
value other than NULL. If msgid is a null pointer, the return value is
undefined. The string returned must not be modified by the program and
can be invalidated by a subsequent call to bind_textdomain_codeset() or
setlocale(3C). If the domainname argument to dgettext(),dcgettext(),
dngettext(), or dcngettext() is a null pointer, the the domain cur‐
rently bound by textdomain() is used.
The normal return value from textdomain() is a pointer to a string con‐
taining the current setting of the domain. If domainname is a null
pointer, textdomain() returns a pointer to the string containing the
current domain. If textdomain() was not previously called and domain‐
name is a null string, the name of the default domain is returned. The
name of the default domain is messages. If textdomain() fails, a null
pointer is returned.
The return value from bindtextdomain() is a null-terminated string con‐
taining dirname or the directory binding associated with domainname if
dirname is NULL. If no binding is found, the default return value is
/usr/lib/locale. If domainname is a null pointer or an empty string,
bindtextdomain() takes no action and returns a null pointer. The string
returned must not be modified by the caller. If bindtextdomain() fails,
a null pointer is returned.
USAGE
These functions impose no limit on message length. However, a text
domainname is limited to TEXTDOMAINMAX (256) bytes.
The gettext(), dgettext(), dcgettext(), ngettext(), dngettext(),
dcngettext(), textdomain(), and bindtextdomain() functions can be used
safely in multithreaded applications, as long as setlocale(3C) is not
being called to change the locale.
The gettext(), dgettext(), dcgettext(), textdomain(), and bindtextdo‐
main() functions work with both Solaris message catalogues and GNU-com‐
patible message catalogues. The ngettext(), dngettext(), dcngettext(),
and bind_textdomain_codeset() functions work only with GNU-compatible
message catalogues. See msgfmt(1) for information about Solaris mes‐
sage catalogues and GNU-compatible message catalogues.
FILES
/usr/lib/locale
default path predicate for message domain files
/usr/lib/locale/locale/LC_MESSAGES/domainname.mo
system default location for file containing messages for language
locale and domainname
/usr/lib/locale/locale/LC_XXX/domainname.mo
system default location for file containing messages for language
locale and domainname for dcgettext() calls where LC_XXX is
LC_CTYPE, LC_NUMERIC, LC_TIME, LC_COLLATE, LC_MONETARY, or LC_MES‐
SAGES
dirname/locale/LC_MESSAGES/domainname.mo
location for file containing messages for domain domainname and
path predicate dirname after a successful call to bindtextdomain()
dirname/locale/LC_XXX/domainname.mo
location for files containing messages for domain domainname, lan‐
guage locale, and path predicate dirname after a successful call to
bindtextdomain() for dcgettext() calls where LC_XXX is one of
LC_CTYPE, LC_NUMERIC, LC_TIME, LC_COLLATE, LC_MONETARY, or LC_MES‐
SAGES
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
│MT-Level │Safe with exceptions │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOmsgfmt(1), xgettext(1), iconv_open(3C), setlocale(3C), attributes(5),
environ(5)SunOS 5.10 1 May 2002 gettext(3C)
