Q64123: PRB: Encountering an INT 01 with WDEB386

Article: Q64123
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.0,3.1
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 05-NOV-1999

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The information in this article applies to:

- Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1 
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SYMPTOMS
========

When debugging an application with WDEB386, the program halts on a breakpoint at
an INT 01 instruction.

CAUSE
=====

An INT 01 is coded into Windows in the Fatal_Error_Handler. This interrupt is
hit when some device driver is doing a fatal exit. The INT 01 is there to make
the debugger useful when diagnosing the fatal error. INT 01 in virtual devices
(VxDs) is generally ignored (treated as a NOP instruction) in the retail version
of Windows. However, if the debugger is installed, the system breaks into the
debugger.

RESOLUTION
==========

Diagnose and correct the cause of the fatal exit.

Additional query words: 3.00 no32bit 3.10

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Keywords          : kb16bitonly 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK300 kbWinSDK310
Version           : WINDOWS:3.0,3.1

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