catopen(3C)

NAME

catopen(), catclose() — open and close a message catalog for reading

SYNOPSIS

#include <nl_types.h>

nl_catd catopen(const char *name, int oflag);

int catclose(nl_catd catd);

DESCRIPTION

The catopen() function opens a message catalog and returns a catalog descriptor. The name specifies the name of the message catalog being opened. A name containing a slash (/) specifies a path name for the message catalog. Otherwise, the environment variable NLSPATH is used (see environ(5)). If NLSPATH specifies more than one path, catopen() returns the catalog descriptor for the first path on which it is able to successfully open the specified message catalog. If NLSPATH does not exist in the environment, or if a message catalog cannot be opened for any NLSPATH-specified path, catopen() uses a system-wide default path. The default is affected by LC_MESSAGES if the value of oflag is NL_CAT_LOCALE. If the value of oflag is zero, the default is affected by the environment variable LANG. See environ(5) for details.

A message catalog descriptor remains valid in a process until the process closes it, or until a successful call to one of the exec() functions. A change in the setting of the LC_MESSAGES category may invalidate existing open catalogs.

If a file descriptor is used to implement message catalog descriptors, the FD_CLOEXEC flag will be set.

If oflag is zero, the LANG environment variable is used to locate the catalog. If oflag is NL_CAT_LOCALE, the LC_MESSAGES category is used to locate the message catalog only if a successful call to setlocale() has been made prior to the call to catopen(). The result of setting oflag to any other value is undefined.

The catclose() function closes the message catalog catd, a message catalog descriptor returned from an earlier successful call to catopen().

APPLICATION USAGE

catopen() and catclose() are thread-safe. These interfaces are not async-cancel-safe. A cancellation point may occur when a thread is executing catopen() or catclose().

RETURN VALUE

Upon success, catopen() returns a message catalog descriptor. Otherwise, catopen() returns a value of (nl_catd)-1 and sets errno to indicate the error.

Upon success, catclose() returns zero. Otherwise, catclose() returns -1 and sets errno to indicate the error.

ERRORS

catopen() fails without opening a message catalog, and sets errno for the last path attempted under any of the following conditions:

[EACCES]: A component of the path prefix denies search permission, or read permission is denied for the named file.
[EMFILE]: The maximum number of file descriptors allowed are currently open.
[ENAMETOOLONG]: The length of the specified path name exceeds PATH_MAX bytes, or the length of a component of the path name exceeds NAME_MAX bytes while _POSIX_NO_TRUNC is in effect.
[ENFILE]: The system file table is full.
[ENOENT]: The named catalog does not exist or the path is null.
[ENOTDIR]: A component of the path prefix is not a directory.

catgets() can be used to provide default messages when called following a failed catopen() (see catgets(3C)). catgets() returns its def_str parameter if it is passed an invalid catalog descriptor.

catclose() fails if the following is true:

[EBADF]: catd is not a valid open message catalog descriptor.

WARNINGS

When using NLSPATH, catopen() does not provide a default value for LANG.

AUTHOR

catopen() and catclose() were developed by HP.

FILES

/usr/include/nl_types.h
/usr/lib/nls/msg: Message catalog default path for core HP-UX products only.

STANDARDS CONFORMANCE

catopen(): AES, SVID3, XPG2, XPG3, XPG4

catclose(): AES, SVID3, XPG2, XPG3, XPG4