DosSubFreeMem

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Syntax

DosSubFreeMem( pOffset, pBlockOffset, ulSize )

Parameters

PVOID pOffset (input)
The Offset of the memory pool that contains the block that should be freed.
PVOID pBlockOffset (input)
The offset of the memory block to be freed. It's important that this is equal to an offset returned by a previous allocation using DosSubAllocMem.
ULONG ulSize (input)
The size in bytes of the memory block that is to be freed.

Returns

APIRET rc

The following values can be returned

0 NO_ERROR
87 ERROR_INVALID_PARAMETER
312 ERROR_DOSSUB_OVERLAP
532 ERROR_DOSSUB_CORRUPTED


Usage Explanation

DosSubFreeMem is used to free a memory block that was allocated with DosSubAllocMem. Size is the size in bytes of the memory block to be freed. It is supposed to be a multiple of 8 bytes, and if not it is rounded up. The maximum value for Size is the size of the memory pool, allocated with DosSubSetMem, minus 64 bytes.

Gotchas

The maximum value for Size is the size of the memory pool, allocated with DosSubSetMem, minus 64 bytes.

Sample Code

#define INCL_DOSMEMMGR
#include <bsememf.h>
#include <os2.h>

PVOID Offset;
PVOID BlockOffset;
ULONG Size;
APIRET rc;

size = 128;

rc = DosSubFreeMem( Offset, BlockOffset, Size);

if (rc != 0)
{
   /* We have an error we must take care of. */
}

See Also