pthread_spin_unlock - Man Page

unlock a spin lock object

Prolog

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

Synopsis

#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

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

The following sections are informative.

Examples

None.

Application Usage

None.

Rationale

If an implementation detects that the value specified by the lock argument to pthread_spin_unlock() does not refer to an initialized spin lock object, it is recommended that the function should fail and report an [EINVAL] error.

If an implementation detects that the value specified by the lock argument to pthread_spin_unlock() refers to a spin lock object for which the current thread does not hold the lock, it is recommended that the function should fail and report an [EPERM] error.

Future Directions

None.

See Also

pthread_spin_destroy(), pthread_spin_lock()

The Base Definitions volume of POSIX.1-2017, Section 4.12, Memory Synchronization, <pthread.h>

Referenced By

pthread.h(0p), pthread_spin_destroy(3p), pthread_spin_lock(3p).

2017 IEEE/The Open Group POSIX Programmer's Manual