Path: utzoo!utgpu!attcan!uunet!husc6!ukma!cwjcc!hal!ncoast!jamiep
From: jamiep@ncoast.UUCP (Jamie Purdon)
Newsgroups: comp.sys.amiga.tech
Subject: Re: LIGHT WEIGHT PROCESSES,  ALPHA VERSION, appendum
Summary: You CAN prevent EXEC from munging your stack (hooray!)
Message-ID: <13283@ncoast.UUCP>
Date: 25 Dec 88 15:46:08 GMT
References: <8812180711.AA23001@postgres.Berkeley.EDU>
Reply-To: jamiep@ncoast.UUCP (Jamie Purdon)
Organization: Cleveland Public Access UN*X, Cleveland, Oh
Lines: 12


EXEC task switching will definitely use your "user" stack.
I see that this situation has "bit" you, since you need to 
allow for this in your "light weight process code".
 
You can change EXEC's behaviour, though, by patching the tc_Launch
and tc_Switch fields in your task structure.  These are
functions that EXEC vectors through just before and just
after switching your task.  You might be able to, at these
points, change the stack areas in use by EXEC.  This way
you could avoid have to check/allow 80-100 bytes of stack
only for EXEC use.