PTHREAD_MUTEX(3) | Library Functions Manual | PTHREAD_MUTEX(3) |
int
pthread_mutex_init(pthread_mutex_t * restrict mutex, const pthread_mutexattr_t * restrict attr);
int
pthread_mutex_destroy(pthread_mutex_t *mutex);
int
pthread_mutex_lock(pthread_mutex_t *mutex);
int
pthread_mutex_trylock(pthread_mutex_t *mutex);
int
pthread_mutex_unlock(pthread_mutex_t *mutex);
pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
The macro PTHREAD_MUTEX_INITIALIZER can be used to initialize a mutex when the default attributes are appropriate and the mutex can be statically allocated. The behavior is similar to pthread_mutex_init() with attr specified as NULL, except that no error checking is done.
The pthread_mutex_destroy() function frees the resources allocated for mutex. It is possible to reinitialize a destroyed mutex, but undefined behavior may follow if the destroyed object is otherwise referenced.
The pthread_mutex_lock() function locks mutex. If the mutex is already locked, the calling thread will block until the mutex becomes available. The error conditions may vary depending on the type of the mutex; see pthread_mutexattr(3) for additional details.
The pthread_mutex_trylock() function locks mutex. If the mutex is already locked, pthread_mutex_trylock() will not block waiting for the mutex, but will return an error condition.
The pthread_mutex_unlock() function unlocks an acquired mutex. When operating with the default mutex type, undefined behavior follows if a thread tries to unlock a mutex that has not been locked by it, or if a thread tries to release a mutex that is already unlocked.
pthread_mutex_destroy() may fail if:
pthread_mutex_lock() may fail if:
pthread_mutex_trylock() may fail if:
pthread_mutex_unlock() may fail if:
July 8, 2010 | NetBSD 6.1 |