HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens

            INT 21,4A - Modify Allocated Memory Block  (SETBLOCK)

       AH = 4A
       BX = new requested block size in paragraphs
       ES = segment of the block (MCB + 1 para)

       on return:
       AX = error code if CF set  (see DOS ERROR CODES)
       BX = maximum block size possible, if CF set and AX = 8

       - modifies memory blocks allocated by  INT 21,48
       - can be used by programs to shrink or increase the size
         of allocated memory
       - PC-DOS version 2.1 and DOS 3.x will actually allocate the largest
         available block if CF is set.  BX will equal the size allocated.
       - see also  INT 21,49

Esc or Alt-X to exit int 21,4a Home/PgUp/PgDn/End ←↑↓→
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