NAME

pthread_spin_unlock - unlock a spin lock object (ADVANCED REALTIME THREADS)

SYNOPSIS

[THR SPI] #include <pthread.h>

int pthread_spin_unlock(pthread_spinlock_t *lock);

DESCRIPTION

The pthread_spin_unlock() function shall release the spin lock referenced by lock which was locked via the pthread_spin_lock() or pthread_spin_trylock() functions. The results are undefined if the lock is not held by the calling thread. If there are threads spinning on the lock when pthread_spin_unlock() is called, the lock becomes available and an unspecified spinning thread shall acquire the lock.

The results are undefined if this function is called with an uninitialized thread spin lock.

RETURN VALUE

Upon successful completion, the pthread_spin_unlock() function shall return zero; otherwise, an error number shall be returned to indicate the error.

ERRORS

The pthread_spin_unlock() function may fail if:

[EINVAL]

An invalid argument was specified.

[EPERM]

The calling thread does not hold the lock.

This function shall not return an error code of [EINTR].

EXAMPLES

None.

APPLICATION USAGE

The pthread_spin_unlock() function is part of the Spin Locks option and need not be provided on all implementations.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

pthread_spin_destroy(), pthread_spin_lock(), the Base Definitions volume of IEEE Std 1003.1-2001, <pthread.h>

CHANGE HISTORY

First released in Issue 6. Derived from IEEE Std 1003.1j-2000.

In the SYNOPSIS, the inclusion of <sys/types.h> is no longer required.