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From: ralf+@cs.cmu.edu (Ralf Brown)
Newsgroups: comp.os.msdos.programmer
Subject: Re: Does a Set S.D.A. function exist in DOS ?
Keywords: TSR, SDA, Byte's March 'Zine.
Message-ID: <1991May13.160822.8281@cs.cmu.edu>
Date: 13 May 91 16:08:22 GMT
References: <17301.282b344c@ul.ie>
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Organization: School of Computer Science, Carnegie Mellon
Lines: 20

In article <17301.282b344c@ul.ie> 8807035@ul.ie writes:
} My problem is I've got the calling parameters for finding the SDA : Func 5dh 
}Subfunc 06 (quoted in the article).  However there are no function parameters
}stated for setting the fgnd_SDA to my_SDA, for example; although it's feasible
}to make a copy of the SDA in some alloc'ed memory and swap it back after 
}the spawned program has run.  


There is no such function, because the DOS kernel refers to absolute addresses
(going through a pointer would needlessly slow down DOS).  You have to
physically make a copy of the SDA and then physically overwrite it with a
previously saved copy.



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