pthread_rwlockattr_destroy - Man Page

destroy and initialize the read-write lock attributes object

Prolog

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

Synopsis

#include <pthread.h>

int pthread_rwlockattr_destroy(pthread_rwlockattr_t *attr);
int pthread_rwlockattr_init(pthread_rwlockattr_t *attr);

Description

The pthread_rwlockattr_destroy() function shall destroy a read-write lock attributes object. A destroyed attr attributes object can be reinitialized using pthread_rwlockattr_init(); the results of otherwise referencing the object after it has been destroyed are undefined. An implementation may cause pthread_rwlockattr_destroy() to set the object referenced by attr to an invalid value.

The pthread_rwlockattr_init() function shall initialize a read-write lock attributes object attr with the default value for all of the attributes defined by the implementation.

Results are undefined if pthread_rwlockattr_init() is called specifying an already initialized attr attributes object.

After a read-write lock attributes object has been used to initialize one or more read-write locks, any function affecting the attributes object (including destruction) shall not affect any previously initialized read-write locks.

The behavior is undefined if the value specified by the attr argument to pthread_rwlockattr_destroy() does not refer to an initialized read-write lock attributes object.

Return Value

If successful, the pthread_rwlockattr_destroy() and pthread_rwlockattr_init() functions shall return zero; otherwise, an error number shall be returned to indicate the error.

Errors

The pthread_rwlockattr_init() function shall fail if:

ENOMEM

Insufficient memory exists to initialize the read-write lock attributes object.

These functions shall not return an error code of [EINTR].

The following sections are informative.

Examples

None.

Application Usage

None.

Rationale

If an implementation detects that the value specified by the attr argument to pthread_rwlockattr_destroy() does not refer to an initialized read-write lock attributes object, it is recommended that the function should fail and report an [EINVAL] error.

Future Directions

None.

See Also

pthread_rwlock_destroy(), pthread_rwlockattr_getpshared()

The Base Definitions volume of POSIX.1-2017, <pthread.h>

Referenced By

pthread.h(0p), pthread_rwlockattr_getpshared(3p).

2017 IEEE/The Open Group POSIX Programmer's Manual