The use of a loop for pthread_cond_wait() and pthread_cond_timedwait() is regarded as good programming practice to handle spurious signals since these APIs are generally implemented using signals on Unix and GNU/Linux systems.

For example, Dave Butenhof's book gives the following example on page 79

Code:

while (data.value = 0) {
     status = pthread_cond_timedwait ( &data.cond, &data.mutex, &timeout);
     if (status == ETIMEOUT ) {
          printf ("Condition wait timed out.\n");
          break;
     } else if (status != 0)
          err_abort(status, "Wait on condition");
}