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From: 8807035@ul.ie
Newsgroups: comp.os.msdos.programmer
Subject: Does a Set S.D.A. function exist in DOS ?
Summary: In search of another undocumented DOS function call.
Keywords: TSR, SDA, Byte's March 'Zine.
Message-ID: <17301.282b344c@ul.ie>
Date: 11 May 91 00:01:16 GMT
Article-I.D.: ul.17301.282b344c
Reply-To: 8807035@ul.ie
Organization: University of Limerick, Ireland
Lines: 22


 At the moment I'm writing a TSR, from inside which I want to be able to spawn 
some programs which are stored on disk using DOS fun 4bh sub 00h.  According 
to Andrew Schulman's ' Undocumented DOS ' article in the March Byte 'zine it 
is possible to do this, without adversely affecting the foreground program, by
making a copy of the Swapable Data Area, and switching the PSPs and DTAs, etc.

 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.  
	
	Anyone got the parameters to the Set SDA function ? 	
	Does it even exist ? 
	Any ideas ? 

	Thanx in advance,
 			Padraig O Mahony.
			8807035@ul.ie
			University of Limerick, Ireland.