Get the process-shared attribute of a read-write lock attribute object
#include <pthread.h> int pthread_rwlockattr_getpshared( const pthread_rwlockattr_t* attr, int* pshared );
- A pointer to the pthread_rwlockattr_t object that you want to get the attribute from.
- A pointer to a location where the function can store the process-shared attribute.
Use the -l c option to qcc to link against this library. This library is usually included automatically.
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.
- The read-write lock attribute object specified by attr is invalid.
Processes and Threads chapter of Getting Started with QNX Neutrino