Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!elroy.jpl.nasa.gov!zardoz.cpd.com!dhw68k!felix!wfischer
From: wfischer@felix.UUCP (Bill Fischer)
Newsgroups: comp.sys.amiga.tech
Subject: What's wrong with this picture??
Keywords: Exec 2.0 Task
Message-ID: <154108@felix.UUCP>
Date: 21 Nov 90 14:53:27 GMT
Sender: news@felix.UUCP
Reply-To: wfischer@felix.UUCP (Bill Fischer)
Organization: FileNet Corp., Costa Mesa, CA
Lines: 51


Assuming that program A started up program B by using the standard
technique of:
  
      LoadSeg()
      CreateProc()    /*  prog.foo  */
      PutMsg()

then program A should be able to 'freeze' program B, to temporarily
suspend it's operation by calling the following fuction:

FreezeProg() {

   Disable();
   tsk = (struct Task*)FindTask("prog.foo");
   Remove(tsk);
   tsk->tc_State = tsk->tc_State + 4;
   Enable();
   return(0);

}

And to 'unfreeze' (or restart) program B by calling the following
function:

MeltProg() {

   Disable();
   if (tsk->tc_State == 8)
       AddTail(&SysBase->TaskReady,tsk);
   else
       AddTail(&SysBase->TaskWait,tsk);
   tsk->tc_State = tsk->tc_State - 4;
   Enable();
   sig = tsk->tc_SigAlloc & tsk->tc_SigRecvd;
   if (sig != 0) Signal(tsk,sig);
   return(0);

}

The problem I have is that some programs don't come back to life
when I call MeltProg(). To make it even more complicated, the
programs that won't 'unfreeze', do so intermittently.... In
other words, sometimes they restart OK and sometimes they won't.
I might add that this technique worked pretty well under KS 1.3
but doesn't work AT ALL under 2.0. Am I breaking any rules here??
Under 2.0 I get a software error - task held requestor.

Regards  B F
  
..!hplabs!fritz!wfischer