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 process-shared attribute for the read-write lock attribute object specified by attr, storing it in pshared. The possible values are:

PTHREAD_PROCESS_SHARED — any thread with access to the read-write lock object's memory can operate it, even if those threads are in different processes.
PTHREAD_PROCESS_PRIVATE — access is limited to threads in the current process.

Note: (QNX Neutrino 7.0.1 or later) If you started procnto with the -s option, set the process-shared attribute to PTHREAD_PROCESS_SHARED for any read-write locks that are shared between processes. For more information, see “Safely sharing mutexes, barriers, and reader/writer locks between processes” in the “QNX Neutrino Microkernel” chapter of the System Architecture guide.

Returns:

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

Classification:

POSIX 1003.1 TSH

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