<<<<<< TIME POSE SUBROUTINE >>>>>>>>>

PAUSE

If they want to quit, do so

    <<<<<< 4 BOTTOM LINES CLEANING SUBROUTINE >>>>>>

BOTCLEAN

If they want to quit, do so

ENCORE5

    <<<<<< REVIEW CLEANING SUBROUTINE >>>>>>

CLEAN

If they want to quit, do so

ENCORE

    <<<<<< CLEAN THE INSIDE OF BOUNDED ARE ONLY >>>>>

BOX

                       ILLUSTRATION                     

GO

 A signal is a means for sending 

 information to a process. The system call

 signal() specifies what a process

 should do upon receipt of a signal.

 If the process P1 sends a signal to process P2, the process P2 may:

  P2

  P1

  P3

     signal

 PA: 1

     <-----

 Ignore the signal ...

 ... transfer control to a specified function, P3 ...

------>    

control

 ... or take a default action, which is normally to terminate a process!

 NOTE: the signal, SIGKILL, is used to KILL a process and 

 can NOT be masked, i.e., it CANNOT be ESCAPED!