DOS/32 Advanced DOS Extender - Programmer's Reference 2.14 - DPMI function 0100h - Allocate DOS Memory Block Allocates a block of memory from the DOS memory pool, ie memory below the 1 MB boundary that is controlled by DOS. Such memory blocks are typically used to exchange data with real mode programs, TSRs, or device drivers. The function returns both the real mode segment base address of the block and one or more descriptors that can be used by protected mode applications to access the block.
In: | AX = 0100h BX = number of (16-byte) paragraphs desired
Out: | if successful: CF clear AX = real mode segment base address of allocated block DX = selector for allocated block if failed CF set AX = error code BX = size of largest available block in paragraphs 0007h - memory control blocks damaged 0008h - insufficient memory 8011h - descriptor unavailable
Notes: a) The selector returned by this function will be a writeable data selector with the base set to the linear address of the allocated memory block and limit set to the size of the memory block. b) Client programs should never modify or free any descriptors allocated by this function. The Free DOS Memory Block DPMI function 0101h will deallocate the descriptors automatically. c) The DOS allocation function (INT 21h function 48h) is used. Copyright © Supernar Systems, Ltd. 1996-2002 All Rights Reserved.