PTHREAD_RWLOCK_INIT(3) BSD Programmer's Manual PTHREAD_RWLOCK_INIT(3)
pthread_rwlock_init - initialize a read/write lock
#include <pthread.h> int pthread_rwlock_init(pthread_rwlock_t *lock, const pthread_rwlockattr_t *attr);
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.
If successful, the pthread_rwlock_init() function will return zero. Oth- erwise an error number will be returned to indicate the error.
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 ob- ject referenced by lock, a previously initialized but not yet destroyed read/write lock. [EINVAL] The value specified by attr is invalid.
pthread_rwlock_destroy(3), pthread_rwlockattr_init(3), pthread_rwlockattr_setpshared(3)
The pthread_rwlock_init() function is expected to conform to Version 2 of the Single UNIX Specification ("SUSv2").
The pthread_rwlock_init() function first appeared in FreeBSD 3.0 and OpenBSD 2.5.
The PTHREAD_PROCESS_SHARED attribute is not supported. MirBSD #10-current August 4, 1998 1