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

DosSubSet

This call is used to initialize a segment or to reset a reallocated segment for suballocation.

Syntax

DosSubSet (SegSelector, Flags, Size)

Parameters

SegSelector (SEL) - input : Target data segment selector.

Flags (USHORT) - input :

0 = Increasing the size of a segment already initialized.

1 = Initializing a segment.
* Size (USHORT) - input : Segment size in bytes.

Return Code

rc (USHORT) - return

Return code descriptions are:

0 NO_ERROR

310 ERROR_DOSSUB_SHRINK

313 ERROR_DOSSUB_BADSIZE

314 ERROR_DOSSUB_BADFLAG

Remarks

To initialize a segment for suballocation, issue DosSubSet before issuing DosSubAlloc and set Flags = 1. The segment must have been allocated with DosAllocSeg or DosAllocShrSeg.

If a segment allocated by a DosAllocSeg call has already been set for suballocation, and a call to DosSubAlloc returns ERROR_DOSSUB_NOMEM, the segment's size can be increased by a call to DosReallocSeg. After reallocation, the segment must be reset by a DosSubSet. Failure to reset the segment after changing its size can yield unpredictable results.

The size parameter should be a multiple of four bytes, or it is rounded up to a multiple of four. Note in DosSubSet, a size parameter of 0 indicates the segment is 64KB, while in DosSubAlloc and DosSubFree, a size parameter of 0 is an error. Other than this special case of 0 meaning 64KB, the minimum size that can be set is 12 bytes.

Example Code

C Binding

#define INCL_DOSMEMMGR USHORT rc = DosSubSet(SegSelector, Flags, Size); SEL SegSelector; /* Segment selector */ USHORT Flags; /* Parameter flags */ USHORT Size; /* Size of a block */ USHORT rc; /* return code */

MASM Binding

EXTRN DosSubSet:FAR INCL_DOSMEMMGR EQU 1 PUSH WORD SegSelector ;Segment selector PUSH WORD Flags ;Parameter flags PUSH WORD Size ;Size of a segment CALL DosSubSet

Returns WORD

Note

Text based on http://www.edm2.com/index.php/DosSubSet

Family API
DOS	Process Manager	DosBeep DosExit DosSleep DosExecPgm
File Manager	DosChDir DosChgFilePtr DosClose DosDelete DosDupHandle DosMkDir DosMove DosQCurDir DosQCurDisk DosSetFileMode DosOpen DosQFileInfo DosRead DosQFileMode DosQFSInfo DosQVerify DosRmDir DosSelectDisk DosFindClose DosFindFirst DosFindNext DosSetFileInfo DosSetVerify DosWrite DosFileLocks DosSetFHandState DosNewSize DosBufReset DosQFHandState DosSetFSinfo DosShutdown
Memory Manager	DosFreeSeg DosSubAlloc DosSubFree DosSubSet DosAllocHuge DosAllocSeg DosReallocHuge DosReallocSeg DosGetHugeShift DosCreateCSAlias
NLS	DosCaseMap DosGetCtryInfo DosGetDBCSEv DosSetCtryCode DosGetCollate DosGetMessage DosInsMessage DosPutMessage
Date and Time	DosSetDateTime DosGetDateTime
Devices	DosDevConfig DosDevIOCtl DosDevIOCtl2
Signals	DosHoldSignal DosSetSigHandler
Misc	BadDynLink DosGetEnv DosGetMachineMode DosGetVersion DosError DosErrClass DosSetVec
KBD	KbdCharIn KbdFlushBuffer KbdGetStatus KbdSetStatus KbdStringIn KbdPeek
VIO	VioGetBuf VioGetConfig VioGetCurPos VioGetCurType VioGetPhysBuf VioReadCellStr VioReadCharStr VioScrollUp VioScrollDn VioScrollLf VioScrollRt VioScrUnLock VioSetCurPos VioSetCurType VioSetMode VioGetMode VioShowBuf VioWrtCellStr VioWrtCharStr VioWrtCharStrAtt VioWrtNAttr VioWrtNCell VioWrtNChar VioWrtTTY VioScrLock VioPopUp
Tools	BIND
Modules	DOSCALLS.DLL VIOCALLS.DLL KBDCALLS.DLL MSG.DLL
Libraries	API.LIB OS2386.LIB FAPI.LIB DOSCALLS.LIB SUBCALLS.LIB