pthread_mutex_getprioceiling(3T)pthread_mutex_getprioceiling(3T)NAMEpthread_mutex_getprioceiling(), pthread_mutex_setprioceiling() - get or
set the prioceiling of a mutex.
SYNOPSISPARAMETERS
mutex Pointer to the mutex whose prioceiling attribute is to
be set/retrieved.
prioceiling
This parameter either points to the memory location
where the prioceiling attribute of mutex is to be
returned (get function) or specifies the new value of
the prioceiling attribute for mutex (set function).
old_ceiling
This parameter points to the memory location where the
old prioceiling attribute of mutex is to be returned
(set function only).
DESCRIPTION
The function will first lock mutex. If the mutex is currently locked,
the calling thread will block until the mutex can be locked. Once the
mutex has been locked, the prioceiling attribute of mutex will be
changed to the value specified in the prioceiling parameter and mutex
will be unlocked. The old priority ceiling for the mutex will be
returned in old_prioceiling.
The function returns the current value of the prioceiling attribute for
mutex in the prioceiling parameter.
Be sure to check for the definition of before using these functions.
Not all systems will support these functions.
RETURN VALUE
Upon successful completion, and return zero. Otherwise, an error number
is returned to indicate the error (the variable is not set).
ERRORS
If any of the following occur, the and functions return the correspond‐
ing error number:
is not defined and these functions are not supported.
For each of the following conditions, if the condition is detected, the
and functions return the corresponding error number:
The priority value
prioceiling is not a legal value.
mutex is not a valid mutex.
The prioceiling protocol is not supported for mutexes.
The caller does not have the appropriate privileges to
change priority ceiling for mutex.
mutex parameter points to an illegal address.
AUTHOR
and were derived from the IEEE POSIX P1003.1c standard.
SEE ALSOpthread_create(3T), pthread_mutex_init(3T), pthread_mutexattr_setprio‐
ceiling(3T), pthread_mutexattr_getprioceiling(3T),
pthread_mutex_lock(3T), pthread_mutex_trylock(3T),
pthread_mutex_unlock(3T).
STANDARDS CONFORMANCE
Pthread Librarpthread_mutex_getprioceiling(3T)