Path: utzoo!attcan!uunet!mcvax!ukc!edcastle!lfcs!sam
From: sam@lfcs.ed.ac.uk (S. Manoharan)
Newsgroups: comp.lang.c
Subject: Re: Coroutines in C
Message-ID: <214@castle.ed.ac.uk>
Date: 22 Aug 89 21:40:20 GMT
Sender: root@castle.ed.ac.uk
Reply-To: sam@lfcs.ed.ac.uk (S. Manoharan)
Lines: 33

In article <5773@ficc.uu.net> peter@ficc.uu.net (Peter da Silva) writes:
>
>                            In many C compilers I wouldn't even need
>to write any assembly code, since setjmp/longjmp can be used to implement
>the context switch.

I have a question. Consider these functions:

event1()			event2()
{				{
  . . .        			   . . .
  get_resourceX();		   . . .
  /*resume:*/ . . .                . . .
}				}

event1() requsts for resourceX. If resourceX is not available
then I want event1() to suspend, and some other event, say
event2() to start. Perhaps, event2() could make the resourceX
available. Once the resourceX is available, I want the function
event1() to start from the /*resume:*/ point. (The code upto
the /*resume:*/ point in event1() should not be re-executed)

Intutively, it appears the co-routines could be applied in this
context. Am I correct? 

And then, is there an easy way to tackle this problem? 
Since there could be a number of event?()s, I think setjmp() 
and longjmp() would be of no help.

Janet: sam@uk.ac.ed.lfcs                      S. Manoharan
Uucp : ..!mcvax!ukc!lfcs!sam                  Dept of Computer Science
Arpa : sam%lfcs.ed.ac.uk@nsfnet-relay.ac.uk   University of Edinburgh
Voice: 031-667 5076 (home)                    Edinburgh EH9 3JZ    UK.