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PTHREAD_SPIN_LOCK(3) Linux Programmer's Manual PTHREAD_SPIN_LOCK(3)

NAME

     pthread_spin_lock, pthread_spin_trylock, pthread_spin_unlock - lock and
     unlock a spin lock

SYNOPSIS

     #include <pthread.h>

     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 feature_test_macros(7)):

     pthread_spin_lock(), pthread_spin_trylock():
         _POSIX_C_SOURCE >= 200112L

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.

RETURN VALUE

     On  success,  these  functions return zero.  On failure, they return an
     error number.

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.

VERSIONS

     These functions first appeared in glibc in version 2.2.

CONFORMING TO

     POSIX.1-2001.

NOTES

     Applying any of the functions described on this page to  an  uninitial-
     ized spin lock results in undefined behavior.

     Carefully read NOTES in pthread_spin_init(3).

SEE ALSO

     pthread_spin_destroy(3), pthread_spin_init(3), pthreads(7)

COLOPHON

     This page is part of release 4.16 of the Linux man-pages project.  A
     description of the project, information about reporting bugs, and the
     latest version of this page, can be found at
     https://www.kernel.org/doc/man-pages/.

Linux 2017-09-30 PTHREAD_SPIN_LOCK(3)