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Q34208: LINK /OV[ERLAYINTERRUPT] Option, Valid Interrupt Numbers

Article: Q34208
Product(s): Microsoft Programming Utilities
Version(s): MS-DOS:3.x,4.x,5.x
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 04-NOV-1999

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The information in this article applies to:

- Microsoft LINK for MS-DOS, versions 3.x, 4.x, 5.x 
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SUMMARY
=======

The Microsoft LINK /OV[ERLAYINTERRUPT] option specifies the interrupt number
used to pass control to an overlay in an application. By default, an application
uses Interrupt 3Fh (63 decimal) for this purpose. Normally, an application uses
the default interrupt unless one overlaid program spawns another overlaid
program.

The /OV option supports interrupts 0h through FFh (0 through 255 decimal).
However, take care to avoid using any interrupts that conflict with MS-DOS. Such
a conflict can be very difficult to debug. Interrupts 3Ch through 43h (60
through 67 decimal) are available as user-defined overlay interrupts without
conflicting with MS-DOS. Consult an MS-DOS programmer's reference for additional
information on the available interrupts.

In Microsoft LINK versions 5.3 and later, the minimum unique abbreviation for
/OVERLAYINTERRUPT changed from /O to /OV.

Additional query words: kbinf

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Keywords          : kb16bitonly 
Technology        : kbAudDeveloper kbZNotKeyword3 kbLINKSearch kbLINK3xDOSSearch kbLINK4xDOSSearch kbLINK5xDOSSearch
Version           : MS-DOS:3.x,4.x,5.x

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