DosReallocSeg

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This call reallocates a segment after discard or changes the size of a segment already allocated.

Syntax

DosReallocSeg (Size, Selector)

Parameters

Size (USHORT) - input
New requested segment size (in bytes). A value of 0 indicates 65536 bytes.
Selector (SEL) - input
Segment to be resized.

Return Code

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

Remarks

DosReallocSeg is called to change the size of an unshared or shared segment allocated with a DosAllocSeg 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.

DosReallocSeg 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 DosReallocSeg 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, and the segment being resized can be either a privilege level 2 or privilege level 3 segment.

To change the size of huge memory allocated by DosAllocHuge, see DosReallocHuge.

Family API Considerations

Some options operate differently in the DOS mode than in the OS/2 mode. Therefore, the following restriction applies to DosReallocSeg 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 = DosReallocSeg(Size, Selector);

USHORT  Size;          /* New size requested in bytes */
SEL     Selector;      /* Selector */

USHORT  rc;            /* return code */

MASM

EXTRN  DosReallocSeg:FAR
INCL_DOSMEMMGR      EQU 1

PUSH   WORD    Size          ;New size requested in bytes
PUSH   WORD    Selector      ;Selector
CALL   DosReallocSeg

Returns WORD