
* top-level:

  * main
    * opihi
      * general_init (lib.shell/startup.c)
      * program_init (pcontrol/pcontrol.c.in)
      	note: launches CheckSystem_Threaded 
      - loop forever
      	* opihi_readline
	* multicommand


* thread:
  * CheckSystem_Threaded
    * CheckBusyJobs
    * CheckDoneJobs
    * CheckKillJobs
    * CheckRespHosts
    * CheckDoneHosts
    * CheckDownHosts
    * CheckIdleHosts (4x, for each job stage: NEEDHOST, WANTHOST, ANYHOST, OLDWANT)
    * CheckLiveHosts

** Host Ops:
   * AddHost
     PutHost (ALLHOSTS)
     PutHost (DOWN)

   * StartHost
     PutHost (IDLE) or PutHost (DOWN) [failure]

   * CheckRespHost
     
   * CheckDown
