Standard C Library Functions pthread_barrier_wait(3C)
NAME
pthread_barrier_wait - synchronize at a barrier
SYNOPSIS
cc -mt [ flag... ] file... [ library... ]
#include
int pthread_barrier_wait(pthread_barrier_t *barrier);
DESCRIPTION
The pthread_barrier_wait() function synchronizes participat-
ing threads at the barrier referenced by barrier. The cal-
ling thread blocks until the required number of threads havecalled pthread_barrier_wait() specifying the barrier.
When the required number of threads have calledpthread_barrier_wait() specifying the barrier, the constant
PTHREAD_BARRIER_SERIAL_THREAD is returned to one unspecified
thread and 0 is returned to each of the remaining threads. At this point, the barrier is reset to the state it had as aresult of the most recent pthread_barrier_init(3C) function
that referenced it.The constant PTHREAD_BARRIER_SERIAL_THREAD is defined in
and its value is distinct from any other value returned by pthread_barrier_wait().
The results are undefined if this function is called with an uninitialized barrier. If a signal is delivered to a thread blocked on a barrier,upon return from the signal handler the thread resumes wait-
ing at the barrier if the barrier wait has not completed (that is, if the required number of threads have not arrived at the barrier during the execution of the signal handler); otherwise, the thread continues as normal from the completed barrier wait. Until the thread in the signal handler returns from it, it is unspecified whether other threads may proceed past the barrier once they have all reached it. A thread that has blocked on a barrier does not prevent any unblocked thread that is eligible to use the same processing resources from eventually making forward progress in its execution.SunOS 5.11 Last change: 30 Jan 2004 1
Standard C Library Functions pthread_barrier_wait(3C)
Eligibility for processing resources is determined by the scheduling policy.RETURN VALUES
Upon successful completion, the pthread_barrier_wait() func-
tion returns PTHREAD_BARRIER_SERIAL_THREAD for a single
(arbitrary) thread synchronized at the barrier and 0 for each of the other threads. Otherwise, an error number is returned to indicate the error.ERRORS
The pthread_barrier_wait() function will fail if:
EINVAL The value specified by barrier does not refer to an initialized barrier object.ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Interface Stability | Committed ||_____________________________|_____________________________|
| MT-Level | MT-Safe |
|_____________________________|_____________________________|
| Standard | See standards(5). ||_____________________________|_____________________________|
SEE ALSO
pthread_barrier_destroy(3C), attributes(5), standards(5)
SunOS 5.11 Last change: 30 Jan 2004 2