Note: This API calls are shared between DOS and Win16 personality.

DPMI is a shared interface for DOS applications to access Intel 80286+ CPUs services. DOS DMPI host provides core services for protected mode applications. Multitasking OS with DOS support also provides DMPI in most cases. Windows standard and extended mode kernel is a DPMI client app. Standard and extended mode kernel differs minimally and shares common codebase. Standard Windows kernel works under DOSX extender. DOSX is a specialized version of 16-bit DPMI Extender (but it is standard DPMI host). Standard mode is just DPMI client, exnhanced mode is DPMI client running under Virtual Machime Manager (really, multitasker which allow to run many DOS sessions). Both modes shares DPMI interface for kernel communication. The OS/2 virtual DOS Protected Mode Interface (VDPMI) device driver provides Version 0.9 DPMI support for virtual DOS machines. Win16 (up to Windows ME) provides Version 0.9 DPMI support.

DPMI host often merged with DPMI extender. Usually DPMI extender provide DPMI host standard services and DOS translation or True DPMI services.

2021/08/05 12:15 · prokushev

Int 31H, AH=00H, AL=0EH




Get Multiple Descriptors


AX = 000EH
CX = number of descriptors to copy
ES:(E)DI = selector:offset of a buffer in the following format:
Offset Length Contents
00H 2 Selector #1 (set by client)
02H 8 Descriptor #1 (returned by host)
0AH 2 Selector #2 (set by client)
0CH 8 Descriptor #2 (returned byhost)
if function successful
Carry flag = clear
and buffer contains copies of the descriptors for the specified selectors

if function unsuccessful
Carry flag = set
AX = error code
8022H	invalid selector
CX = number of descriptors successfully copied


Copies one or more local descriptor table (LDT) entries into a client buffer.

If an error occurs because of an invalid selector or descriptor, the function returns the number of descriptors which were successfully copied in CX. All of the descriptors which were copied prior to the one that failed are valid.

32-bit programs must use ES:EDI to point to the buffer. 16-bit programs should use ES:DI.

Refer to the rules for descriptor usage in Appendix D.

See also


Process manager INT 2FH 1680H, 1687H
Memory manager
Misc INT 2FH 1686H, 168AH
2021/08/13 16:23 · prokushev

en/docs/dpmi/api/int31/00/0e.txt · Last modified: 2021/08/27 03:53 by prokushev