FreeBSD Manual Pages
PTHREAD_RWLOCK_WRLO... FreeBSD Library Functions Manual PTHREAD_RWLOCK_WRLO... NAME pthread_rwlock_wrlock, pthread_rwlock_timedwrlock, pthread_rwlock_trywrlock -- acquire a read/write lock for writing SYNOPSIS #include <pthread.h> int pthread_rwlock_wrlock(pthread_rwlock_t *lock); int pthread_rwlock_timedwrlock(pthread_rwlock_t *lock, const struct timespec *abstime); int pthread_rwlock_trywrlock(pthread_rwlock_t *lock); DESCRIPTION The pthread_rwlock_wrlock() function blocks until a write lock can be ac- quired against lock. The pthread_rwlock_timedwrlock() function 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 immedi- ately 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 will fail if: [EBUSY] The calling thread is not able to acquire the lock without blocking. The pthread_rwlock_timedwrlock() function will 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. [ENOMEM] Insufficient memory exists to initialize the lock (ap- plies to statically initialized locks only). SEE ALSO pthread_rwlock_unlock(3) STANDARDS The pthread_rwlock_wrlock(), pthread_rwlock_timedwrlock(), and pthread_rwlock_trywrlock() functions are expected to conform to Version 2 of the Single UNIX Specification ("SUSv2"). HISTORY The pthread_rwlock_wrlock() function first appeared in FreeBSD 3.0 and OpenBSD 2.5. The pthread_rwlock_timedwrlock() function first appeared in OpenBSD 4.8. FreeBSD 13.0 February 13, 2019 FreeBSD 13.0
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | STANDARDS | HISTORY
Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=pthread_rwlock_wrlock&sektion=3&manpath=OpenBSD+6.9>