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pthread_rwlockattr_getpshared()

Get the process-shared attribute of a read-write lock attribute object

Synopsis:

#include <pthread.h>

int pthread_rwlockattr_getpshared( 
       const pthread_rwlockattr_t* attr,
       int* pshared );

Arguments:

attr: A pointer to the pthread_rwlockattr_t object that you want to get the attribute from.
pshared: A pointer to a location where the function can store the process-shared attribute.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The pthread_rwlockattr_getpshared() function gets the the process-shared attribute for the read-write lock attribute object specified by attr, storing it in pshared.

To let any thread with access to the read-write lock object's memory operate it, the process-shared attribute must be set to PTHREAD_PROCESS_SHARED, even if those threads are in different processes. Set the process-shared attribute to PTHREAD_PROCESS_PRIVATE to limit access to threads in the current process.

Returns:

EOK: Success.
EINVAL: The read-write lock attribute object specified by attr is invalid.

Classification:

POSIX 1003.1 THR TSH

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	Yes
Thread	Yes