# man > TEXTDOMAIN(3)

[TEXTDOMAIN(3)](https://www.chedong.com/phpMan.php/man/TEXTDOMAIN/3/markdown)                         Library Functions Manual                         [TEXTDOMAIN(3)](https://www.chedong.com/phpMan.php/man/TEXTDOMAIN/3/markdown)



## NAME
       textdomain - set domain for future gettext() calls

## SYNOPSIS
### #include <libintl.h>

       **char** ***** **textdomain** **(const** **char** ***** _domainname_**);**

## DESCRIPTION
       The **textdomain** function sets or retrieves the current message domain.

       A message domain is a set of translatable _msgid_ messages. Usually, every software package has
       its own message domain. The domain name is used to determine  the  message  catalog  where  a
       translation is looked up; it must be a non-empty string.

       The  current  message domain is used by the **gettext**, **ngettext** functions, and by the **dgettext**,
       **dcgettext**, **dngettext** and **dcngettext** functions when called with a NULL domainname argument.

       If _domainname_ is not NULL, the current message domain is set to _domainname_.  The  string  the
       function stores internally is a copy of the _domainname_ argument.

       If _domainname_ is NULL, the function returns the current message domain.

## RETURN VALUE
       If  successful,  the  **textdomain**  function returns the current message domain, after possibly
       changing it. The resulting string is valid until the next **textdomain** call  and  must  not  be
       modified or freed. If a memory allocation failure occurs, it sets **errno** to **ENOMEM** and returns
       NULL.

## ERRORS
       The following error can occur, among others:

       **ENOMEM** Not enough memory available.

## BUGS
       The return type ought to be **const** **char** *****, but is **char** ***** to avoid warnings in C code predating
       ANSI C.

## SEE ALSO
       [**gettext**(3)](https://www.chedong.com/phpMan.php/man/gettext/3/markdown), [**ngettext**(3)](https://www.chedong.com/phpMan.php/man/ngettext/3/markdown), [**bindtextdomain**(3)](https://www.chedong.com/phpMan.php/man/bindtextdomain/3/markdown), **bind**___**textdomain**___**[codeset**(3)](https://www.chedong.com/phpMan.php/man/codeset/3/markdown)



GNU gettext 0.20.1.124-32cf                   May 2001                                 [TEXTDOMAIN(3)](https://www.chedong.com/phpMan.php/man/TEXTDOMAIN/3/markdown)