posix_spawnattr_setcwd_np()

Arguments:

attrp

A pointer to the spawn attributes object that you want to modify.

dirfd

A file descriptor for the directory that you want to use as the child process's initial working directory, obtained by calling open(), specifying O_DIRECTORY in the flags.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The posix_spawnattr_setcwd_np() function sets the current working directory attribute in the given spawn attributes object. You must have already initialized the spawn attributes object by calling posix_spawnattr_init().

This setting takes effect only if the POSIX_SPAWN_SETCWD flag is set in the spawn attributes; to set this flag, call posix_spawnattr_setxflags(). This setting also takes effect before any file actions are made, including trying to open the executable.

If posix_spawn() is called after posix_spawnattr_setcwd_np(), you must provide a path relative to the new path chosen by posix_spawnattr_setcwd_np(). As a result, the child process will use the current working directory specified by posix_spawnattr_setcwd_np().

For more information about spawn attributes, see the entry for posix_spawn().

Returns:

EOK

Success.

EINVAL

The attrp pointer does not refer to a valid attribute structure.

Examples:

posix_spawnattr_t spawnattr; 
if (posix_spawnattr_init(&spawnattr) != 0) {
    perror("posix_spawnattr_init");
    return 1;
}

char *dir_to_open = "/proc/boot";
dirfd = open(dir_to_open, O_RDONLY | O_DIRECTORY);
if (dirfd < 0) {
    perror("open");
    return 1;
}

if (posix_spawnattr_setxflags(&spawnattr, POSIX_SPAWN_SETCWD) != 0) {
    perror("posix_spawnattr_setxflags");
    return 1;
}

if (posix_spawnattr_setcwd_np(&spawnattr, dirfd) != 0) {
    perror("posix_spawnattr_setcwd_np");
    return 1;
}

err = posix_spawn(&pid, argv[0], NULL, &spawnattr, child_argv,
                  child_envp);
if (err != 0) {
    perror("posix_spawn");
    return 1;
}

Classification:

QNX OS