Editing DOS Protected Mode Interface (section)

=== Compatibility ===
While Windows 3.0 implements "true DPMI"<ref name="Lipe_1992_MSDOSEXT"/> and reports support for DPMI 0.9,<ref name="NetBIOS_2004"/> DPMI version 1.0 was never implemented in [[Microsoft Windows]], so most programs and DOS extenders were mostly only written for version 0.9. Few extenders, however, implement "true DPMI".

Beta versions of [[Qualitas]] [[386MAX]] implemented "true DPMI" and could run Windows' KRNL386.EXE from the command line, but it was claimed that was disabled in the released product in an internal email.<ref name="Lipe_1992_MSDOSEXT"/> However, DPMIONE (by Bob Smith based on the 386MAX code) can do it. Currently [[DPMIONE]] and [[386MAX|386<sup>MAX</sup>]] is also the only DPMI host which supports DPMI 1.0 completely (e.g. uncommitted memory) and they are the main supporter of DPMI 1.0.<ref name="Sokolov_1998_DPMI10"/>

The KRNL386.SYS (aka "MultiMAX") of [[DR&nbsp;DOS "Panther"]] and [[DR DOS "StarTrek"|"StarTrek"]], which has been under development since 1991,<ref group="nb" name="NB_Panther"/> and the [[EMM386.EXE]] memory managers of [[Novell DOS 7]],<ref name="Schneider_1994"/> [[Caldera OpenDOS]] and [[DR-DOS]] 7.02 and higher have built-in support for DPMI when loaded with the <code>/DPMI[=ON]</code> option. KRNL386.SYS even had a command line option <code>/VER=0.9|1.0</code> to provide support for either DPMI 1.0 or 0.9.<ref name="Schulman_1994_Undocumented-DOS"/> DOS API translation was referred to as "called interrupt 21 from protected mode". [[Multiuser DOS]], [[Datapac System Manager|System Manager]] and [[REAL/32]] support DPMI as well.

The most famous separate DPMI kernel is probably [[CWSDPMI]]; it supports DPMI 0.9, but no undocumented "DOS API translation".
Another variant called PMODE by "TRAN" aka [[Thomas Pytel]] was popular with 32-bit programmers during the [[demo scene]] of the 1990s.
Many games used DOS/4GW, which was developed by [[Rational Systems]] as a subset of [[DOS/4G]] and was distributed with the [[Watcom C compiler]].

HDPMI (part of [[HX DOS Extender]]) provides "DOS API translation" and almost complete DPMI 1.0 implementation.