NAME
catopen, catclose - open/close a message catalog SYNOPSIS
#include
nlcatd catopen(const char *name, int flag); int catclose(nlcatd catalog); DESCRIPTION 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 descrip‐ tors then the FDCLOEXEC flag will be set. The argument name specifies the name of the message catalog to be opened. If name specifies and 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 environ‐ ment, 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 LCMESSAGES locale setting when the flag argument is NLCATLOCALE and on the LANG environment variable when the flag argument is 0. Changing the LCMESSAGES 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 NLCATLOCALE then it will use the current locale setting for LCMESSAGES. Otherwise it will use the LANG environment variable. The function catclose() closes the message catalog identified by cata‐ log. It invalidates any subsequent references to the message catalog defined by catalog. RETURN VALUE The function catopen() returns a message catalog descriptor of type
nlcatd on success. On failure, it returns (nlcatd) -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 LCMESSAGES May be the source of the LCMESSAGES locale setting, and thus determine the language to use if flag is set to NLCATLOCALE. LANG The language to use if flag is 0. ATTRIBUTES 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 │ └───────────┴───────────────┴─────────────┘ CONFORMING TO
POSIX.1-2001. It is unclear what the source was for the constants MCLoadBySet and MCLoadAll (see below). NOTES
The above is the POSIX.1-2001 description. The glibc value for NLCATLOCALE is 1. (Compare MCLoadAll below.) The default path varies, but usually looks at a number of places below /usr/share/locale. Linux notes These functions are available for Linux since libc 4.4.4c. In the case of linux libc4 and libc5, the catalog descriptor nlcatd is a mmap(2)'ed area of memory and not a file descriptor. The flag argument to catopen() should be either MCLoadBySet (=0) or MCLoadAll (=1). The former value indicates that a set from the catalog is to be loaded when needed, whereas the latter causes the initial call to catopen() to load the entire catalog into memory. The default search path varies, but usually looks at a number of places below /etc/locale and /usr/lib/locale. SEE ALSO catgets(3), setlocale(3) COLOPHON
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be found at http://www.kernel.org/doc/man-pages/.
GNU 2001-12-14 CATOPEN(3)