PTHREAD_RWLOCK_WRLOCK(3)

NAME
pthread_rwlock_wrlock, pthread_rwlock_timedwrlock, pthread_rwlock_trywrlock - acquire a read/write lock for writing

LIBRARY
libpthread

SYNOPSIS
#include <pthread.h>
int
pthread_rwlock_wrlock(pthread_rwlock_t *lock);
int
pthread_rwlock_timedwrlock(pthread_rwlock_t * restrict lock, const struct timespec * restrict abstime);
int
pthread_rwlock_trywrlock(pthread_rwlock_t *lock);

DESCRIPTION
The pthread_rwlock_wrlock() function blocks until a write lock can be acquired against lock.

The pthread_rwlock_timedwrlock() performs the same action, but will not wait beyond abstime to obtain the lock before returning.

The pthread_rwlock_trywrlock() function performs the same action as pthread_rwlock_wrlock(), but does not block if the lock cannot be immediately obtained.

The results are undefined if the calling thread already holds the lock at the time the call is made.

RETURN VALUES
If successful, the pthread_rwlock_wrlock(), pthread_rwlock_timedwrlock(), and pthread_rwlock_trywrlock() functions will return zero. Otherwise an error number will be returned to indicate the error.

ERRORS
The pthread_rwlock_trywrlock() function shall fail if:

[EBUSY]
    The calling thread is not able to acquire the lock without blocking.

The pthread_rwlock_timedrdlock() function shall fail if:

[ETIMEDOUT]
    The time specified by abstime was reached before the lock could be obtained.

The pthread_rwlock_wrlock(), pthread_rwlock_timedwrlock(), and pthread_rwlock_trywrlock() functions may fail if:

[EDEADLK]
    The calling thread already owns the read/write lock (for reading or writing).

[EINVAL]
    The value specified by lock is invalid.

SEE ALSO
pthread_rwlock_destroy(3), pthread_rwlock_init(3), pthread_rwlock_rdlock(3), pthread_rwlock_unlock(3)

STANDARDS
pthread_rwlock_wrlock(), pthread_rwlock_timedwrlock(), and pthread_rwlock_trywrlock() conform to p1003.1-96.