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From: tim@hoptoad.uucp (Tim Maroney)
Newsgroups: comp.sys.mac
Subject: Re: VBL tasks, time manager
Message-ID: <3093@hoptoad.uucp>
Date: Wed, 30-Sep-87 19:18:22 EDT
Article-I.D.: hoptoad.3093
Posted: Wed Sep 30 19:18:22 1987
Date-Received: Sun, 4-Oct-87 23:35:21 EDT
References: <5273@jade.BERKELEY.EDU>
Reply-To: tim@hoptoad.UUCP (Tim Maroney)
Organization: Sun Microsystems, TOPS Division, Berkeley
Lines: 24

In article <5273@jade.BERKELEY.EDU> jmm@thoth30.berkeley.edu () writes:
>1.  Can someone send me some example code of
>VBL tasks (preferably in LSPascal, but
>I can also read C )?  I was playing around
>with them last night and managed to
>produce some pretty graphics and sound
>8-) but nothing useful.
>
>(Even if you don't have example code,
>I'd be interested to know what you do
>with VBL interrupts.  It seems as if
>the 'no memory manager' restriction
>is a big problem)

Sorry, but I'd be fired if I broadcast proprietary code.  However, what I
use the vertical retrace for is resending packets and noticing the user
timeout in the networking protocol TCP.  There is no need for storage
allocation in either of these operations.  For interrupt-level code that
does need to allocate storage (e.g., network packet reception from a socket
listener), I pre-allocate it at the synchronous level and queue the blocks
up for later use.
-- 
Tim Maroney, {ihnp4,sun,well,ptsfa,lll-crg}!hoptoad!tim (uucp)
hoptoad!tim@lll-crg (arpa)3