Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!rochester!udel!new
From: new@udel.EDU (Darren New)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Official Warnings...
Keywords: tas
Message-ID: <14420@louie.udel.EDU>
Date: 1 May 89 18:06:58 GMT
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In article <8904302141.AA21035@explorer.dgp.toronto.edu> pavel@dgp.toronto.edu (Pavel Rozalski) writes:
>Occasionally one may wish to have a lightweight method of accessing
>shared memory without the burden of an OS call. 

As I remember, Forbid() and Permit() (or at least the asm macros thereof)
are just one or two instructions long and don't involve any OS calls.
I think they work by just incrementing or decrementing flags, maybe in
the Task structure (requiring that you find this via the OS, but only once).
How much more lightweight do you want?  -- Darren