PTHREAD_SPIN_UNLOCK(3P)

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.

NAME
pthread_spin_unlock — unlock a spin lock object

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>

COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .