PTHREAD_RWLOCK_INIT(3) BSD Library Functions Manual PTHREAD_RWLOCK_INIT(3)
NAME
pthread_rwlock_init -- initialize a read/write lock
SYNOPSIS
#include <pthread.h>
int
pthread_rwlock_init(pthread_rwlock_t *restrict rwlock, const pthread_rwlockattr_t *restrict attr);
DESCRIPTION
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
If successful, the pthread_rwlock_init() function will return zero. Otherwise, an error number will be returned to indicate the error.
SEE ALSO
pthread_rwlock_destroy(3), pthread_rwlockattr_init(3), pthread_rwlockattr_setpshared(3)
STANDARDS
The pthread_rwlock_init() function is expected to conform to Version 2 of the Single UNIX Specification (``SUSv2'').
ERRORS
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 rwlock, a previously initialized but not yet
destroyed read/write lock.
[EINVAL] The value specified by attr is invalid.
HISTORY
The pthread_rwlock_init() function first appeared in FreeBSD 3.0.
BUGS
The PTHREAD_PROCESS_SHARED attribute is not supported.
BSD
August 4, 1998 BSD