en:docs:fapi:dossuballoc

This is part of Family API which allow to create dual-os version of program runs under OS/2 and DOS

Note: This is legacy API call. It is recommended to use 32-bit equivalent

2021/09/17 06:47 · prokushev
2021/08/20 05:18 · prokushev

DosSubAlloc

This call suballocates portions of a segment allocated by DosAllocSeg or DosAllocShrSeg, and initialized by DosSubSet.

Syntax

DosSubAlloc (SegSelector, BlockOffset, Size)

Parameters

Return code descriptions are:

  • 0 NO_ERROR
  • 311 ERROR_DOSSUB_NOMEM
  • 313 ERROR_DOSSUB_BADSIZE

Remarks

Before a segment allocated by DosAllocSeg or DosAllocShrSeg can be suballocated, it must first be initialized for suballocation by a call to DosSubSet.

Allocation size must be a multiple of four bytes. Otherwise, it is rounded up to a multiple of four bytes. The maximum value for the size parameter is the size that was set with DosSubSet minus 8. Note that no paragraph (16-byte) alignment is required; all requests are serviced on a byte alignment basis.

A suballocated block of memory in a suballocated segment is freed by a call to DosSubFree.

Example Code

C Binding

#define INCL_DOSMEMMGR
 
USHORT  rc = DosSubAlloc(SegSelector, BlockOffset, Size);
 
SEL              SegSelector;   /* Segment selector */
PUSHORT          BlockOffset;   /* Block Offset (returned) */
USHORT           Size;          /* Size of requested block */
 
USHORT           rc;            /* return code */

MASM Binding

EXTRN  DosSubAlloc:FAR
INCL_DOSMEMMGR      EQU 1
 
PUSH   WORD    SegSelector   ;Segment selector
PUSH@  WORD    BlockOffset   ;Block Offset (returned)
PUSH   WORD    Size          ;Size of requested block
CALL   DosSubAlloc

Returns WORD

Note


en/docs/fapi/dossuballoc.txt · Last modified: 2021/09/17 10:49 by prokushev