The function int pthread_setcancelstate(int state, int* oldstate); Atomically sets the cancelability state to 'state' and returns the old cancelability state in the location referenced by 'oldstate'. 'state' can either be PTHREAD_CANCEL_ENABLE, or PTHREAD_CANCEL_DISABLE. The cancelability state of a newly created thread is PTHREAD_CANCEL_ENABLE. It returns a 0 on success. It may return an error code of: [EINVAL] The specified state is not PTHREAD_CANCEL_ENABLE or PTHREAD_CANCEL_DISABLE. It will not return EINTR.