PTHREAD_COND_WAIT(3) |
FreeBSD Library Functions Manual |
PTHREAD_COND_WAIT(3) |
NAME
pthread_cond_wait —
wait on a condition variable
LIBRARY
POSIX Threads Library (libpthread, -lpthread)
SYNOPSIS
#include < pthread.h>
int
pthread_cond_wait( pthread_cond_t *cond, pthread_mutex_t *mutex);
DESCRIPTION
The
pthread_cond_wait() function atomically blocks the current thread waiting on the condition variable specified by
cond, and releases the mutex specified by
mutex. The waiting thread unblocks only after another thread calls
pthread_cond_signal(3), or
pthread_cond_broadcast(3) with the same condition variable, and the current thread reacquires the lock on
mutex.
RETURN VALUES
If successful, the
pthread_cond_wait() function will return zero. Otherwise an error number will be returned to indicate the error.
ERRORS
The
pthread_cond_wait() function will fail if:
-
[
EINVAL]
-
The value specified by
cond or the value specified by
mutex is invalid.
-
[
EPERM]
-
The specified
mutex was not locked by the calling thread.
STANDARDS
The
pthread_cond_wait() function conforms to ISO/IEC 9945-1:1996 (“POSIX.1”).