pthread_mutexattr_getpshared()

Get the process-shared attribute from a mutex attribute object

Synopsis:

#include <pthread.h>

int pthread_mutexattr_getpshared( 
            const pthread_mutexattr_t* attr, 
            int* pshared );

Arguments:

attr

A pointer to the pthread_mutexattr_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_mutexattr_getpshared() function gets the process-shared attribute from the mutex attribute object attr and stores it in the memory pointed to by pshared. The possible values are:

• PTHREAD_PROCESS_SHARED — any thread that has access to the memory where the mutex is allocated can operate on it, even if the mutex is allocated in memory that's shared by multiple processes.
• PTHREAD_PROCESS_PRIVATE — the mutex can be accessed only by threads created within the same process as the thread that initialized the mutex; if threads from other processes try to access the PTHREAD_PROCESS_PRIVATE mutex, the behavior is undefined.

Returns:

EOK

Success.

EINVAL

The mutex attribute object specified by attr is invalid.

Classification:

POSIX 1003.1 THR TSH

See also:

pthread_cond_init(), pthread_create(), pthread_mutex_init(), pthread_mutexattr_setpshared(), pthread_mutexattr_setrecursive(), pthread_mutexattr_settype()