This example demonstrate the use of mutexes in RTLinux programs.The Linux init_module() function creates a mutex and locks it.Then it creates an RT-thread that also tries to lock the mutex and blocks.After a 500 ms pause, the Linux threads unlocks the mutex, which can now be locked by the RT-thread. The time spent in pthread_mutex_lock is reportedto show that the RT-thread actually blocks.To run the example, type make test. You have to be at a Linux console (no X)to see the results.