Q24910: Memory Not Freed by DOS 2.x for exec or spawn with P_OVERLAY

Article: Q24910
Product(s): See article
Version(s): 4.00 5.00 5.10
Operating System(s): MS-DOS
Keyword(s): ENDUSER | tar57672 | mspl13_c
Last Modified: 21-SEP-1988

Within DOS Versions 2.x only, recurrent use of an exec function or a
spawn function with P_OVERLAY eventually causes a return indicating
that there is no more available RAM memory.

This is a DOS Versions 2.x problem, whose exact nature is unknown.
Microsoft has traced the problem to the point where DOS corrupted
memory, and memory is not being freed back to DOS Versions 2.x.

If you encounter this problem, upgrade to DOS Versions 3.x, which
do not have this problem.

It appears that only the exec() family (or spawn() with P_OVERLAY
specified) is affected by this DOS problem. The spawn() family (except
when P_OVERLAY is specified) seems to work correctly.

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