Path: utzoo!utgpu!water!watmath!clyde!bellcore!tness7!tness1!sugar!peter
From: peter@sugar.uu.net (Peter da Silva)
Newsgroups: comp.sys.amiga
Subject: Re: Need info on exceptions
Message-ID: <2538@sugar.uu.net>
Date: 24 Aug 88 11:23:12 GMT
References: <3793@louie.udel.EDU>
Organization: Sugar Land Unix - Houston, TX
Lines: 19

In article ... iphwk%MTSUNIX1.BITNET@cunyvm.cuny.edu (Bill Kinnersley) writes:
> Unfortunately it can't.  "To avoid serious problems, the interrupt
> routine must not use any of the memory allocation or deallocation
> functions"--RKM.  That's apparently because critical system code
> is surrounded by Forbid(), but not Disable().

> That doesn't seem to leave much that interrupts can do.  Once again,
> we're stuck with polling (and this on a multitasking OS).

You shouldn't be doing much in an interrupt, on any system. These are real
hardware-type interrupts, you know. For software interrupts, you can
probably get away with doing memory hacking, since you know that the task
which posted them wasn't doing anything dangerous when it was posted. But,
really, you don't need to do anything like that, anyway... because you can
signal a sleeping task to do the actual grunt-work.

For this application, you should probably have the computation done with a
subtask which signals the sleeping main program at appropriate points in
the calculation.