Q58653: CodeView Does Not Support Debugging Spawned Process

Article: Q58653
Product(s): Microsoft Programming Utilities
Version(s): 2.2,3.0,3.11,3.14,4.0,4.01,4.05,4.1
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 26-JUN-2001

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The information in this article applies to:

- Microsoft CodeView for MS-DOS, versions 2.2, 3.0, 3.11, 3.14, 4.0, 4.01, 4.05, 4.1 
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The following are several reasons why CodeView doesn't provide
debugging support for spawned processes in MS-DOS:

1. MS-DOS is not a multitasking operating system. CodeView cannot start another
  thread/process to watch the execution of the spawned process.

2. MS-DOS does not provide debugging support for the MS-DOS BIOS calls
  (Interrupt 21h). Since all spawn() and exec() functions in MS-DOS must go
  through the BIOS to run, CodeView cannot follow the spawned program.

3. MS-DOS only recognizes 640K of memory; therefore, there is insufficient
  memory to debug a large program, since both the parent and child processes
  must reside in memory at the same time.

Additional query words: kbinf 2.20 3.00 4.00 4.10

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Keywords          : kb16bitonly 
Technology        : kbAudDeveloper kbCodeView kbZNotKeyword3 kbCodeView220DOS kbCodeView300DOS kbCodeView311DOS kbCodeView314DOS kbCodeView400DOS kbCodeView401DOS kbCodeView405DOS kbCodeView410DOS
Version           : :2.2,3.0,3.11,3.14,4.0,4.01,4.05,4.1

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