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

See also:

pthread_rwlockattr_destroy(), pthread_rwlockattr_init(), pthread_rwlockattr_setpshared()

Processes and Threads chapter of Getting Started with QNX Neutrino