pthread_mutex_trylock(3) - NetBSD Manual Pages

PTHREAD_MUTEX_LOCK(3)   NetBSD Library Functions Manual  PTHREAD_MUTEX_LOCK(3)


NAME

     pthread_mutex_lock, pthread_mutex_trylock -- acquire a lock on a mutex


LIBRARY

     POSIX Threads Library (libpthread, -lpthread)


SYNOPSIS

     #include <pthread.h>

     int
     pthread_mutex_lock(pthread_mutex_t *mutex);

     int
     pthread_mutex_trylock(pthread_mutex_t *mutex);


DESCRIPTION

     The pthread_mutex_lock() function locks mutex.  If the mutex is already
     locked, the calling thread will block until the mutex becomes available.

     The pthread_mutex_trylock() function locks mutex.  If the mutex is
     already locked, pthread_mutex_trylock() will not block waiting for the
     mutex, but will return an error condition.


RETURN VALUES

     If successful, pthread_mutex_lock() and pthread_mutex_trylock() will
     return zero, otherwise an error number will be returned to indicate the
     error.


ERRORS

     pthread_mutex_lock() may fail if:

     [EDEADLK]          A deadlock would occur if the thread blocked waiting
                        for mutex.

     [EINVAL]           The value specified by mutex is invalid.

     pthread_mutex_trylock() shall fail if:

     [EBUSY]            Mutex is already locked.

     pthread_mutex_trylock() may fail if:

     [EINVAL]           The value specified by mutex is invalid.


SEE ALSO

     pthread_mutex_destroy(3), pthread_mutex_init(3), pthread_mutex_unlock(3)


STANDARDS

     pthread_mutex_lock() and pthread_mutex_trylock() conform to ISO/IEC
     9945-1:1996 (``POSIX.1'').

NetBSD 5.0.1                   January 30, 2003                   NetBSD 5.0.1