ID Number: Q58653
2.20 2.30 2.35 3.00 3.10 3.11 3.14
MS-DOS
Summary:
The following are several reasons why CodeView doesn't provide
debugging support for spawned processes under DOS:
1. DOS is not a multitasking operating system. CodeView cannot start
another thread/process to watch the execution of the spawned
process.
2. DOS does not provide debugging support for the DOS BIOS calls (int
21h). Since all spawn() and exec() functions under DOS have to go
through the BIOS to run, CodeView cannot follow the spawned
program.
3. DOS only recognizes 640K of memory; therefore, there is
insufficient memory to debug a large program, since both the parent
and child processes have to reside in memory at the same time.