pthread_mutex_unlock(3T) pthread_mutex_unlock(3T)
NAME
pthread_mutex_unlock() - unlock a mutex.
SYNOPSIS
PARAMETERS
mutex Pointer to the mutex to be unlocked.
DESCRIPTION
The function is called by the owner of the mutex referenced by mutex to unlock the mutex. The manner in that the mutex is released is
dependent upon the mutex's type attribute. For normal and default mutexes, undefined behavior will result if is called on an unlocked
mutex or by a thread that is not the current owner. For recursive and error-checking mutexes, an error is returned if is called on an
unlocked mutex or by a thread which is not the current owner.
For recursive mutexes, the owner must call as many times as the mutex was locked before another thread can lock the mutex.
If there are threads blocked on the mutex referenced by mutex when releases the mutex, the scheduling policy is used to determine which
thread will acquire the mutex next.
RETURN VALUE
Upon successful completion, returns zero. Otherwise, an error number is returned to indicate the error (the variable is not set).
ERRORS
For each of the following conditions, if the condition is detected, the function returns the corresponding error number:
[EINVAL] mutex is not an initialized mutex.
[EPERM] The calling thread does not own mutex. On HP-UX, this error is not detected for or mutexes.
[EFAULT] mutex parameter points to an illegal address.
AUTHOR
was derived from the IEEE POSIX P1003.1c standard and HP extensions.
SEE ALSO
pthread_mutex_init(3T), pthread_mutex_destroy(3T), pthread_mutex_lock(3T), pthread_mutex_trylock(3T).
STANDARDS CONFORMANCE
Pthread Library pthread_mutex_unlock(3T)