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Q38294: Overwriting End of HALLOC Causes Crash at Termination

Article: Q38294
Product(s): See article
Version(s): 5.00 5.10 | 5.00 5.10
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | | mspl13_c
Last Modified: 12-DEC-1988

The following message appearing at the termination of a program can be
caused by overwriting past the end of a block of memory allocated by
the halloc function:

   Memory allocation error: Cannot load command.com

The bytes following a halloc'd block are used by DOS for keeping
track of memory allocation, and DOS may be unable to load command.com
upon completion of your process if this area is corrupted.

This error can also conceivably be caused by overwriting blocks of
memory allocated by other functions such as malloc, _nmalloc, and _fmalloc.

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