Section: Linux Programmer's Manual (3)
pthread_spin_lock, pthread_spin_trylock, pthread_spin_unlock -
lock and unlock a spin lock
int pthread_spin_lock(pthread_spinlock_t *lock);
int pthread_spin_trylock(pthread_spinlock_t *lock);
int pthread_spin_unlock(pthread_spinlock_t *lock);
Compile and link with -pthread.
Feature Test Macro Requirements for glibc (see
_POSIX_C_SOURCE >= 200112L
function locks the spin lock referred to by
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.
on a lock that is already held by the caller
or a lock that has not been initialized with
results in undefined behavior.
function is like
except that if the spin lock referred to by
is currently locked,
then, instead of spinning, the call returns immediately with the error
function unlocks the spin lock referred to
If any threads are spinning on the lock,
one of those threads will then acquire the lock.
on a lock that is not held by the caller results in undefined behavior.
On success, these functions return zero.
On failure, they return an error number.
may fail with the following errors:
The system detected a deadlock condition.
fails with the following errors:
The spin lock is currently locked by another thread.
These functions first appeared in glibc in version 2.2.
Applying any of the functions described on this page to
an uninitialized spin lock results in undefined behavior.
Carefully read NOTES in
This page is part of release 5.07 of the Linux
A description of the project,
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and the latest version of this page,
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