Dear curious WDOSX user,

Yes! WDOSX 0.94 (non-beta) is out!

Dear Web search robot,

This page is about WDOSX, a 32 bit DOS extender. WDOSX is freeware.

It supports programs written in assembly language, Borland Delphi 2/3 and Borland C/C++. It may support other compilers that create Win 32 (PE) executables as well but this has not been tested yet.

After some sort of a rather long delay, the final version 0.94 is available for download.

Download WDOSX 0.94 (190853 bytes)

Don't forget to use the -d option when unzipping!

What is this NASM thing all about?

NASM is a freeware assembler / disassembler written by Simon Tatham and Julian Hall. It supports all current x86 processors, including MMX instructions. NASM uses the Intel style syntax, so programs written for NASM look very similar to MASM / TASM code.

To learn more about NASM, visit their site!

NASM can assemble your sourcecode to flat form binary format. This is basically a pure binary file with no .exe header at all containing all the (32 bit) code and initialized data of your program. WDOSX can load and execute these flat form binary files. No need for a linker.

What other executable formats does WDOSX support?

For programs written in assembly, WDOSX supports 32 bit DOS "MZ" executables and flat model executables linked to PE format that don't use the Win 32 API. The latter format is recommended if you have access to a linker like TLINK32.EXE. It allowes for using the ".model flat" directive along with splitting your program into .code, .data and .data? (BSS) sections.

For programs written in a HLL using the standard libraries and startup code that came with your compiler, WDOSX provides a PE executable loader with a small Win32 API emulation. You should compile your code to a Win32 command line application. This does not mean that you cannot use DPMI calls, interrupts and so on in your code, it's just that most compilers and their standard libraries do support Win32 command line as a target executable format. Your applications will run in a DPMI 32 environment, even if they are launched from within a Windows95 / NT DOS box.

Again: WDOSX isn't guaranteed to work with every program written in any language using any compiler. There're just too many possibilities.

Will my program be able to run with the LINUX DOSEMU?

That depends. WDOSX itself won't crash. The stub manager from the WDOSX 0.93 package runs fine (as of DOSEMU 0.63.anything), beeing a WDOSX application itself written in and compiled with Borland C. However, consider that the DOS emulator is still under development and the way your program is dealing with the hardware / DPMI API and so on may cause it to crash like other DOS extended programs do in the DOSEMU even though they run fine in DOS boxes of other operating systems.

Is there a DPMI specification somewhere on the Net?

Yes.

This is one place where you can obtain it from.

I don't like your DOS extender, are there other ones available as freeware?

You can find them all over the Net. One good place to look for is:

But I really don't like your DOS extender. Is there a way to tell you that?

Send me email