PTHREAD_RWLOCK_INIT(3) Library Functions Manual PTHREAD_RWLOCK_INIT(3)

pthread_rwlock_initinitialize a read/write lock

#include <pthread.h>

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

The () 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 () with an already initialized lock are undefined.

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

The pthread_rwlock_init() function will fail if:

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The system lacked the necessary resources (other than memory) to initialize the lock.
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Insufficient memory exists to initialize the lock.
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The caller does not have sufficient privilege to perform the operation.

The pthread_rwlock_init() function may fail if:

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

The PTHREAD_PROCESS_SHARED attribute is not supported.

August 4, 1998 Mac OS X 12