DosSubFree

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This call frees memory previously allocated by DosSubAlloc.

Syntax

DosSubFree (SegSelector, BlockOffset, Size)

Parameters

SegSelector (SEL) - input 
Data segment selector.
BlockOffset (USHORT) - input 
Memory block offset. The value specified must equal the BlockOffset returned on a previous DosSubAlloc call.
Size (USHORT) - input 
Size, in bytes, of the block to be freed.

Return Code

rc (USHORT) - return
Return code descriptions are:
  • 0 NO_ERROR
  • 312 ERROR_DOSSUB_OVERLAP
  • 313 ERROR_DOSSUB_BADSIZE

Remarks

DosSubFree specifies the offset of a block of memory previously suballocated by a DosSubAlloc request. If the block specified overlaps memory in the segment that is not suballocated, an error is returned. Like DosSubAlloc, the size parameter must be a multiple of four bytes; otherwise, it is rounded up to a multiple of four bytes.

The allocated segment is freed by calling DosFreeSeg.

Bindings

C

#define INCL_DOSMEMMGR

USHORT  rc = DosSubFree(SegSelector, BlockOffset, Size);

SEL     SegSelector;   /* Segment selector */
USHORT  BlockOffset;   /* Offset of memory block to free */
USHORT  Size;          /* Size of block in bytes */

USHORT  rc;            /* return code */

MASM

EXTRN  DosSubFree:FAR
INCL_DOSMEMMGR      EQU 1

PUSH   WORD    SegSelector   ;Segment selector
PUSH   WORD    BlockOffset   ;Offset of memory block to free
PUSH   WORD    Size          ;Size of block in bytes
CALL   DosSubFree

Returns WORD