The function int pthread_condattr_setpshared(pthread_condattr_t *attr, int pshared); shall set the process-shared attribute in an initialized attributes object referenced by attr. The process-shared attribute is set to PTHREAD_PROCESS_SHARED to permit a condition variable to be operated upon by any thread that has access to the memory where the condition variable is allocated, even if the condition variale is allocated in memory that is shared by multiple processes. If the process-shared attribute is set to PTHREAD_PROCESS_PRIVATE, the condition variable shall only be operated upon by threads create within the same process as the thread that initialized the condition varible; if threads of differing processes attempt to operate on such a condition variable, the behavior is undefined. If successful, the pthread_condattr_setpshared() function shall return zero; The pthread_condattr_setpshared() function may fail if: [EINVAL] The value specified by attr is invalid. [EINVAL] The new value specified for the attribute is outside the range of legal values for that attribute.