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PTHREAD_SPIN_LOCK(3) FreeBSD Library Functions Manual PTHREAD_SPIN_LOCK(3)
NAME pthread_spin_lock, pthread_spin_trylock, pthread_spin_unlock - lock or unlock a spin lock
LIBRARY POSIX Threads Library (libpthread, -lpthread)
SYNOPSIS #include <pthread.h>
int pthread_spin_lock(pthread_spinlock_t *lock);
int pthread_spin_trylock(pthread_spinlock_t *lock);
int pthread_spin_unlock(pthread_spinlock_t *lock);
DESCRIPTION The pthread_spin_lock() function will acquire lock if it is not currently owned by another thread. If the lock cannot be acquired immediately, it will spin attempting to acquire the lock (it will not sleep) until it becomes available.
The pthread_spin_trylock() function is the same as pthread_spin_lock() except that if it cannot acquire lock immediately it will return with an error.
The pthread_spin_unlock() function will release lock, which must have been previously locked by a call to pthread_spin_lock() or pthread_spin_trylock().
RETURN VALUES If successful, all these functions will return zero. Otherwise, an error number will be returned to indicate the error.
None of these functions will return EINTR.
ERRORS The pthread_spin_lock(), pthread_spin_trylock() and pthread_spin_unlock() functions will fail if:
[EINVAL] The value specified by lock is invalid or is not initialized.
The pthread_spin_lock() function may fail if:
[EDEADLK] The calling thread already owns the lock.
The pthread_spin_trylock() function will fail if:
[EBUSY] Another thread currently holds lock.
The pthread_spin_unlock() function may fail if:
[EPERM] The calling thread does not own lock. FreeBSD 5.2, and in 1:1 Threading Library (libthr, -lthr) in FreeBSD 5.3.
BUGS The implementation of pthread_spin_lock(), pthread_spin_trylock() and pthread_spin_unlock() is expected to conform to IEEE Std 1003.2 ("POSIX.2").
FreeBSD 14.0-RELEASE-p11 January 22, 2004 FreeBSD 14.0-RELEASE-p11