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#     Sandia Corporation. 
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#
# $Id: status_daemon_flow 2572 2004-08-05 20:25:03Z nwdauch $
#

Process Flow Diagram for CIToolkit Status Daemon
------------------------------------------------

The diagram below shows how the various parts of the Status Daemon are
born, how they communicate, and what happens when they die.

--- indicates process flow
=== indicates data flow
... indicates return codes


 Server::_fork_status_checks()
       |                                  
     fork! ---->---.
       |           | (completely separate from parent)
       |         fork! ---->---.
       |           |           |
       |<== pid ==/|         setsid (start a new process group)
       |           |           |
       |         (exit)        |
       |                       |
       |           .-----<-----.
       |           |
       |     Server::Checks::start()       
       |           | 
       |           | initialize tests and set timer	
       |            \                     
       |    while(1) >-- foreach action -->--.
       |            /        /               |    
       |           |        |            background() 
       |           |        ^                |    
       |           |        |              fork! ---->--.
       |           |        |                |          |
       |           |         \-------<------/|          |
       |           |                         |     Status::run_my_test() 
       |           |                         |          |
       |           |             reset timer |      Status::saferun()
       |           |                         |          |
       |            \---<--- sleep()---<----/         fork! ----->---.
       |                                                |            |
       |                                                |     exec test script
       |                                                |            |
       |                                                |<==stdout==/|
       |                                                |            |
       |                                                |<....rc...(exit)
       |                                                |
       |<========= socket (flattened object) <=========/|
       |                                                |
       |                                              (exit) 
       ...