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From: kds@physics (Kevin Stokes)
Newsgroups: comp.os.msdos.programmer,alt.msdos.programmer
Subject: Re: DOS EXEC function: How to regain control?
Message-ID: <21986@duke.cs.duke.edu>
Date: 19 Feb 91 21:19:31 GMT
References: <5534@trantor.harris-atd.com>
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In article <5534@trantor.harris-atd.com> sonny@trantor.harris-atd.com (Bob Davis) writes:
>
>	I am trying to write a TSR to invoke a command when
>the hot key triggers by making use of INT 21h, Function 4Bh (the
>DOS EXEC function). 

  If you interrupt the operation of a DOS program with a hotkey, you
can't turn around and use a DOS call to do anything with making sure
you haven't interrupted a DOS call which was in progress when you struck
the hot key.  IE DOS is not re-entrant.  Also, since function 4Bh uses
the disk drive, a new DTA address and everything will have to be set.
  Writing a TSR which actually loads and executes a program is a very 
complex project.  There are some books which contain the info needed, but
none of them are very complete.
           -Kevin

--
	Kevin Stokes				1-919-684-8256
	Duke University Dept. of Physics	kds@phy.duke.edu
	Durham, N.C.      27706