catopen(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ENVIRONMENT | ATTRIBUTES | VERSIONS | STANDARDS | HISTORY | SEE ALSO | COLOPHON

catopen(3)              Library Functions Manual              catopen(3)

NAME         top

       catopen, catclose - open/close a message catalog

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <nl_types.h>

       nl_catd catopen(const char *name, int flag);
       int catclose(nl_catd catalog);

DESCRIPTION         top

       The function catopen() opens a message catalog and returns a
       catalog descriptor.  The descriptor remains valid until
       catclose() or execve(2).  If a file descriptor is used to
       implement catalog descriptors, then the FD_CLOEXEC flag will be
       set.

       The argument name specifies the name of the message catalog to be
       opened.  If name specifies an absolute path (i.e., contains a
       '/'), then name specifies a pathname for the message catalog.
       Otherwise, the environment variable NLSPATH is used with name
       substituted for %N (see locale(7)).  It is unspecified whether
       NLSPATH will be used when the process has root privileges.  If
       NLSPATH does not exist in the environment, or if a message
       catalog cannot be opened in any of the paths specified by it,
       then an implementation defined path is used.  This latter default
       path may depend on the LC_MESSAGES locale setting when the flag
       argument is NL_CAT_LOCALE and on the LANG environment variable
       when the flag argument is 0.  Changing the LC_MESSAGES part of
       the locale may invalidate open catalog descriptors.

       The flag argument to catopen() is used to indicate the source for
       the language to use.  If it is set to NL_CAT_LOCALE, then it will
       use the current locale setting for LC_MESSAGES.  Otherwise, it
       will use the LANG environment variable.

       The function catclose() closes the message catalog identified by
       catalog.  It invalidates any subsequent references to the message
       catalog defined by catalog.

RETURN VALUE         top

       The function catopen() returns a message catalog descriptor of
       type nl_catd on success.  On failure, it returns (nl_catd) -1 and
       sets errno to indicate the error.  The possible error values
       include all possible values for the open(2) call.

       The function catclose() returns 0 on success, or -1 on failure.

ENVIRONMENT         top

       LC_MESSAGES
              May be the source of the LC_MESSAGES locale setting, and
              thus determine the language to use if flag is set to
              NL_CAT_LOCALE.

       LANG   The language to use if flag is 0.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌─────────────────────────────────┬───────────────┬─────────────┐
       │ Interface                       Attribute     Value       │
       ├─────────────────────────────────┼───────────────┼─────────────┤
       │ catopen()                       │ Thread safety │ MT-Safe env │
       ├─────────────────────────────────┼───────────────┼─────────────┤
       │ catclose()                      │ Thread safety │ MT-Safe     │
       └─────────────────────────────────┴───────────────┴─────────────┘

VERSIONS         top

       The above is the POSIX.1 description.  The glibc value for
       NL_CAT_LOCALE is 1.  The default path varies, but usually looks
       at a number of places below /usr/share/locale.

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       POSIX.1-2001.

SEE ALSO         top

       catgets(3), setlocale(3)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
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Linux man-pages 6.9.1          2024-05-02                     catopen(3)

Pages that refer to this page: catgets(3)environ(7)locale(7)