Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!utgpu!utcsri!flaps
From: flaps@utcsri.UUCP
Newsgroups: comp.sys.amiga
Subject: How do I force a context switch?
Message-ID: <5175@utcsri.UUCP>
Date: Fri, 31-Jul-87 16:58:37 EDT
Article-I.D.: utcsri.5175
Posted: Fri Jul 31 16:58:37 1987
Date-Received: Sat, 1-Aug-87 16:23:05 EDT
Reply-To: flaps@utcsri.UUCP (Alan J Rosenthal)
Distribution: world
Organization: University of Toronto
Lines: 25


How does a task tell the exec that it wants to give up the rest of its
current cpu-time quantum?  I am currently using Delay(1L), which will
probably work fine but is exceedingly ugly.

In case you want to know, this is why I need to force a context
switch.  I'm writing a program where several tasks are started.
Through use of priorities, all are started at once.  One of these
functions sets a global variable that others need.  If through bad luck
another function starts running first and tries to use this global
variable before it's set, it has to allow the first function to set it
before proceeding.  Since this is the second line in the code of the
first function, all it has to do is give up the rest of its cpu quantum
this time around which will give the other task a chance to run before
this one runs any more, thus setting the variable.

-- 

      //  Alan J Rosenthal
     //
 \\ //        flaps@csri.toronto.edu, {seismo!utai or utzoo}!utcsri!flaps,
  \//              flaps@toronto on csnet, flaps at utorgpu on bitnet.


"To be whole is to be part; true voyage is return."