pthread_spin_unlock(3) - NetBSD Manual Pages

PTHREAD_SPIN_UNLOCK(3)  NetBSD Library Functions Manual PTHREAD_SPIN_UNLOCK(3)


NAME

     pthread_spin_unlock -- release a spin lock


LIBRARY

     POSIX Threads Library (libpthread, -lpthread)


SYNOPSIS

     #include <pthread.h>

     int
     pthread_spin_unlock(pthread_spinlock_t *lock);


DESCRIPTION

     The pthread_spin_unlock() function is used to release the read/write lock
     previously obtained by pthread_spin_lock() or pthread_spin_trylock().


RETURN VALUES

     If successful, the pthread_spin_unlock() function will return zero.  Oth-
     erwise an error number will be returned to indicate the error.

     The results are undefined if lock is not held by the calling thread.


ERRORS

     The pthread_spin_unlock() function may fail if:

     [EINVAL]           The value specified by lock is invalid.


SEE ALSO

     pthread_spin_destroy(3), pthread_spin_init(3), pthread_spin_lock(3),
     pthread_spin_trylock(3)


STANDARDS

     pthread_rwlock_unlock() conforms to IEEE Std 1003.1-2001 (``POSIX.1'').


CAVEATS

     Applications using spinlocks are vulnerable to the effects of priority
     inversion.  Applications using real-time threads (SCHED_FIFO, SCHED_RR)
     should not use these interfaces.  Outside carefully controlled environ-
     ments, priority inversion with spinlocks can lead to system deadlock.
     Mutexes are preferable in nearly every possible use case.

NetBSD 5.0.1                     May 26, 2008                     NetBSD 5.0.1