pthread_spin_lock, pthread_spin_trylock, pthread_spin_unlock - lock and unlock a spin lock
Contents
Caveats
Applying any of the functions described on this page to an uninitialized spin lock results in undefined
behavior.
Carefully read NOTES in pthread_spin_init(3).
Description
The pthread_spin_lock() function locks the spin lock referred to by lock. If the spin lock is currently
unlocked, the calling thread acquires the lock immediately. If the spin lock is currently locked by
another thread, the calling thread spins, testing the lock until it becomes available, at which point the
calling thread acquires the lock.
Calling pthread_spin_lock() on a lock that is already held by the caller or a lock that has not been
initialized with pthread_spin_init(3) results in undefined behavior.
The pthread_spin_trylock() function is like pthread_spin_lock(), except that if the spin lock referred to
by lock is currently locked, then, instead of spinning, the call returns immediately with the error
EBUSY.
The pthread_spin_unlock() function unlocks the spin lock referred to lock. If any threads are spinning
on the lock, one of those threads will then acquire the lock.
Calling pthread_spin_unlock() on a lock that is not held by the caller results in undefined behavior.
Errors
pthread_spin_lock() may fail with the following errors:
EDEADLOCK
The system detected a deadlock condition.
pthread_spin_trylock() fails with the following errors:
EBUSY The spin lock is currently locked by another thread.
History
glibc 2.2. POSIX.1-2001.
Library
POSIX threads library (libpthread, -lpthread)
Name
pthread_spin_lock, pthread_spin_trylock, pthread_spin_unlock - lock and unlock a spin lock
Return Value
On success, these functions return zero. On failure, they return an error number.
See Also
pthread_spin_destroy(3), pthread_spin_init(3), pthreads(7) Linux man-pages 6.9.1 2024-05-02 pthread_spin_lock(3)
Standards
POSIX.1-2008.
Synopsis
#include<pthread.h>intpthread_spin_lock(pthread_spinlock_t*lock);intpthread_spin_trylock(pthread_spinlock_t*lock);intpthread_spin_unlock(pthread_spinlock_t*lock); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): pthread_spin_lock(), pthread_spin_trylock(): _POSIX_C_SOURCE >= 200112L
