pthread_rwlock_unlock()
Unlock a read-write lock
Synopsis:
#include <pthread.h>
int pthread_rwlock_unlock( pthread_rwlock_t* rwl );
Arguments:
- rwl
- A pointer to a pthread_rwlock_t object that you want to unlock.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The pthread_rwlock_unlock() function unlocks a read-write lock referenced by rwl. The read-write lock may become available for any threads that were blocked on the read-write lock, depending on whether the read-write lock had been locked in exclusive or shared mode.
The read-write lock should be owned by the calling thread. If the
calling thread doesn't hold the lock, no error status is returned, and
the behavior of this read-write lock is now undefined.
Returns:
- EOK
- Success.
- EAGAIN
- On the first use of a statically initialized read-write lock, insufficient system resources existed to initialize the read-write lock.
- EFAULT
- A fault occurred when the kernel tried to access rwl.
- EINVAL
- The read-write lock rwl is invalid.
- EPERM
- No thread has a read or write lock on rwl or the calling thread doesn't have a write lock on rwl.
Classification:
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | Yes |
| Thread | Yes |