Int 21 Fn 48  - DOS 2+ - Allocate Memory                                   [D]

   AH = 48h
   BX = number of paragraphs to allocate

Return: CF clear if successful
       AX = segment of allocated block
   CF set on error
       AX = error code (07h,08h) (see AH=59h)
       BX = size of largest available block

Notes: DOS 2.1-6.0 coalesces free blocks while scanning for a block to
     allocate
   .COM programs are initially allocated the largest available memory
     block, and should free some memory with AH=49h before attempting any
     allocations
   under the FlashTek X-32 DOS extender, EBX contains a protected-mode
     near pointer to the allocated block on a successful return

See Also: AH=49h,AH=4Ah,AH=58h,AH=83h