catopen(3C)

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.

If catopen() is invoked from setuid or setgid programs with owner root, the environment variable NLSPATH is not directly used to locate message catalogs. Instead, the paths which are available both in the configuration file /etc/default/nlspath and environment variable NLSPATH are considered to locate message catalogs. See nlspath(4) for details.

Example: If the environment variable is set to:

and the /etc/default/nlspath configuration file has an entry:

only path /usr/lib/nls/msg/%L/%N.cat is considered for locating catalog files. This feature is provided only for backward compatibility for those setuid or setgid root programs which are depending on the NLSPATH environment variable. All new setgid or setuid root programs should not depend on the NLSPATH environment variable and should only use absolute path names.

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.

A file descriptor is used to implement the message catalog descriptor and the close-on-exec flag is set for the message catalog descriptor (see fcntl(2)).

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().

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:

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:

WARNINGS

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

AUTHOR

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

FILES

SEE ALSO

fcntl(2), catgets(3C), setlocale(3C), nlspath(4), environ(5), thread_safety(5).

STANDARDS CONFORMANCE

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

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