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Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ihnp4!alberta!ubc-vision!ubc-cs!manis
From: manis@ubc-cs.UUCP
Newsgroups: comp.sys.atari.st
Subject: Re: desk accessories
Message-ID: <1432@ubc-cs.UUCP>
Date: Mon, 1-Jun-87 21:17:17 EDT
Article-I.D.: ubc-cs.1432
Posted: Mon Jun  1 21:17:17 1987
Date-Received: Thu, 4-Jun-87 01:46:35 EDT
References: <16225@cca.CCA.COM>
Reply-To: manis@ubc-cs.UUCP (Vincent Manis)
Organization: UBC Department of Computer Science
Lines: 32

In article <16225@cca.CCA.COM> m204help@cca.CCA.COM (Keith Hedger) writes:

>Is it possible to make any program a desk accessorie ?
Within limitations, it is possible to write a desk accessory to do almost
anything that a full-fledged application can do. Exceptions (apart from the
obvious ones such as memory--a DA is loaded at boot time, and takes up space
whether you use it or not) include the inability for DA's to have menus, and 
some restrictions imposed by various language implementations. Programming
systems which I *know* support the creation of DA's include the Atari
C Developer's Kit, Mark Williams C, and TDI Modula-2. Many other systems
support the creation of DA's, but those are the ones whose documentation I
have seen. (I have never written a DA, so please don't ask me for advice).
As far as I know, it is *impossible* to write a DA in Atari Basic.

In general, a DA writer had better understand GEM pretty clearly. Although 
it doesn't cover DA's specifically, the Sybex "GEM Programmer's Guide" is an
invaluable introduction.

>Could I have my main program loaded and also have 2-3 other programs
>either written by myself or purchased, loaded as accessories ?
You can't turn an application into a DA or vice versa. Other than that, the
only other restriction is the limit of 6 DA slots that GEM imposes. 

-----
Vincent Manis                {seismo,uw-beaver}!ubc-vision!ubc-cs!manis
Dept. of Computer Science    manis@cs.ubc.cdn
Univ. of British Columbia    manis%ubc.csnet@csnet-relay.arpa  
Vancouver, B.C. V6T 1W5      manis@ubc.csnet
(604) 228-6770 or 228-3061

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