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*The requested Size value is rounded up to the next paragraph (16-byte).  
*The requested Size value is rounded up to the next paragraph (16-byte).  


==Example Code==
==Bindings==
=== C Binding===
===C===
<PRE>
<PRE>
#define INCL_DOSMEMMGR
#define INCL_DOSMEMMGR
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</PRE>
</PRE>


===MASM Binding===
===MASM===
<PRE>
<PRE>
EXTRN  DosReallocHuge:FAR
EXTRN  DosReallocHuge:FAR
INCL_DOSMEMMGR      EQU 1
INCL_DOSMEMMGR      EQU 1


PUSH  WORD    NumSeg       ;Number of 65536-byte segments requested
PUSH  WORD    NumSeg     ;Number of 65536-byte segments requested
PUSH  WORD    Size         ;Number of bytes in last segment
PUSH  WORD    Size       ;Number of bytes in last segment
PUSH  WORD    Selector     ;Selector
PUSH  WORD    Selector   ;Selector
CALL  DosReallocHuge
CALL  DosReallocHuge


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</PRE>
</PRE>


[[Category:Dos]]
[[Category:Dos16]]

Latest revision as of 01:49, 26 January 2020

This call changes the size of memory originally allocated by DosAllocHuge.

Syntax

DosReallocHuge (NumSeg, Size, Selector)

Parameters

NumSeg (USHORT) - input
Number of 65536 byte segments requested.
Size (USHORT) - input
Number of bytes requested in the last non-65536 byte segment. A value of 0 indicates none.
Selector (SEL) - input
Selector returned on a previous DosAllocHuge.

Return Code

rc (USHORT) - return
Return code descriptions are:
  • 0 NO_ERROR
  • 8 ERROR_NOT_ENOUGH_MEMORY
  • 87 ERROR_INVALID_PARAMETER

Remarks

DosReallocHuge is called to change the size of unshared or shared huge memory allocated by DosAllocHuge. The selector used for this call must be the one returned by the DosAllocHuge request.

Normally, segments allocated as shared (AllocFlags bits 0 and 1 were set) cannot be decreased in size. However, if AllocFlags bit 3 was also set, the shared segment's size can be decreased.

DosReallocHuge is also called to reallocate a segment allocated as discardable (AllocFlags bit 2 set) after the segment is discarded by the system. The call to DosReallocHuge automatically locks the segment for access by the caller, the same as if a DosLockSeg had been issued.

Note
This request may be issued from privilege level 2 or 3. However, only a privilege level 3 huge segment is valid.

Family API Considerations

Some options operate differently in the DOS mode than in the OS/2 mode. Therefore, the following restriction applies to DosReallocHuge when coding for the DOS mode:

  • The requested Size value is rounded up to the next paragraph (16-byte).

Bindings

C

#define INCL_DOSMEMMGR

USHORT  rc = DosReallocHuge(NumSeg, Size, Selector);

USHORT  NumSeg;        /* Number of 65536-byte segments requested */
USHORT  Size;          /* Number of bytes in last segment */
SEL     Selector;      /* Selector */

USHORT  rc;            /* return code */

MASM

EXTRN  DosReallocHuge:FAR
INCL_DOSMEMMGR      EQU 1

PUSH   WORD    NumSeg     ;Number of 65536-byte segments requested
PUSH   WORD    Size       ;Number of bytes in last segment
PUSH   WORD    Selector   ;Selector
CALL   DosReallocHuge

Returns WORD