NAME    [Toc]    [Back]

     pthread_rwlock_init -- initialize a read/write lock

LIBRARY    [Toc]    [Back]

     Reentrant C Library (libc_r, -lc_r)

SYNOPSIS    [Toc]    [Back]

     #include <pthread.h>

     int
     pthread_rwlock_init(pthread_rwlock_t *lock,
	 const pthread_rwlockattr_t *attr);

DESCRIPTION    [Toc]    [Back]

     The pthread_rwlock_init() function is used to initialize a read/write
     lock, with attributes specified by attr.  If attr is NULL, the default
     read/write lock attributes are used.

     The results of calling pthread_rwlock_init() with an already initialized
     lock are undefined.

RETURN VALUES    [Toc]    [Back]

     If successful, the pthread_rwlock_init() function will return zero.  Otherwise
 an error number will be returned to indicate the error.

SEE ALSO    [Toc]    [Back]

     pthread_rwlockattr_init(3), pthread_rwlockattr_setpshared(3),
     pthread_rwlock_destroy(3)

STANDARDS    [Toc]    [Back]

     The pthread_rwlock_init() function is expected to conform to Version 2 of
     the Single UNIX Specification (``SUSv2'').

ERRORS    [Toc]    [Back]

     The pthread_rwlock_init() function will fail if:

     [EAGAIN]		The system lacked the necessary resources (other than
			memory) to initialize the lock.

     [ENOMEM]		Insufficient memory exists to initialize the lock.

     [EPERM]		The caller does not have sufficient privilege to perform
 the operation.

     The pthread_rwlock_init() function may fail if:

     [EBUSY]		The system has detected an attempt to re-initialize
			the object referenced by lock, a previously initialized
 but not yet destroyed read/write lock.

     [EINVAL]		The value specified by attr is invalid.

HISTORY    [Toc]    [Back]

     The pthread_rwlock_init() function first appeared in FreeBSD 3.0.

BUGS    [Toc]    [Back]

     The PTHREAD_PROCESS_SHARED attribute is not supported.


FreeBSD 5.2.1			August 4, 1998			 FreeBSD 5.2.1