Re: Load Overlay Function

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Article #3825

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#3825

From: Jerzy Tarasiuk
Date: Fri, 16 Oct 1992 16:54

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>>>>> On Wed, 14 Oct 1992 11:15:32 GMT, danne@dynas.se (Daniel Helander) said:
Daniel> I need help using the MS-DOS load overlay function (int 21h, funtion 4b03).
Daniel> The parameter block passed in es:bx looks like:
Daniel> LOADOVERLAY STRUC
Daniel> 	loStartSegment		dw ?
Daniel> 	loRelocationFactor	dw ?
Daniel> LOADOVERLAY ENDS
Daniel>   - What is this relocation factor?
Daniel>   - Can it be set to another value in order to relocate the overlay
Daniel>     to another address than it was loaded to?
Yes. If you plan to move the loaded overlay before executing it, should
set the relocation factor to segment where it will be executed. Normally
it should be same as start segment. If you know what is .EXE structure:
there is a relocation table in it, the table contains list of addresses
where segment to which program is loaded is to be added. Load overlay
loads to StartSegment and add RelocationFactor at these addresses.

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Message-ID: <JT.92Oct16175404@fizyk1.fuw.edu.pl>

Path: arc1-ca.pugleaf.net!sparky!uunet!mcsun!sunic!fuw.edu.pl!cocos!jt

References: <1992Oct14.111532.3601@dynas.se>

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Path: arc1-ca.pugleaf.net!sparky!uunet!mcsun!sunic!fuw.edu.pl!cocos!jt
From: jt@fuw.edu.pl (Jerzy Tarasiuk)
Subject: Re: Load Overlay Function
In-Reply-To: danne@dynas.se's message of Wed, 14 Oct 1992 11:15:32 GMT
Message-ID: <JT.92Oct16175404@fizyk1.fuw.edu.pl>
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Organization: Warsaw University Physics Dept.
References: <1992Oct14.111532.3601@dynas.se>
Date: Fri, 16 Oct 1992 16:54:04 GMT
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