This document defines the coverage for the pthread_mutexattr_init function:

Assertion	Tested?
1		YES
2		NO  *Looking for indicators to judge if initialized mutexes 
		     are affected. The prioceiling or protocol attributes may
		     be relied on, but they belong to REALTIME_THREADS scope, 
		     which is low priority in the schedule.
3		YES
4		NO  *Looking for a way to use up the memory without screwing
 		     up the machine.

Note: 
