winevdm on 64-bit Windows

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Download latest version (unstable)

16-bit Windows (Windows 1.x, 2.x, 3.0, 3.1, etc.) on 64-bit Windows

An altered version of winevdm (a 16-bit Windows emulator), ported to 64-bit Windows.

How to compile(Visual Studio)

• Install Visual Studio 2017
• Edit PropertySheet.props
• Compile

How to compile(cmake)

git clone https://github.com/otya128/winevdm.git
cd winevdm
mkdir build
cd build
cmake ..
make

How to run

• If you get an error that VCRUNTIME140.dll is missing, install Microsoft Visual C++ Redistributable for Visual Studio 2017 (32-bit)
• Drag and drop Win16 executable file to otvdm.exe or execute otvdmw.exe.

How to install

• Download or compile
• Edit install.inf
• Right-click on install.inf and select "Install"
• You can execute Win16 binaries directly!

If you install v0.4.x, you should replace [Strings] section of install.inf with these and install install.inf again.

[Strings]
NtVdm64=SOFTWARE\Microsoft\Windows NT\CurrentVersion\NtVdm64
CommandLine="""%m"" %c"
MappedExeName=otvdm.exe

How does it work?

This program contains the following items

• CPU Emulator
  • 64-bit Windows cannot modify LDT(NtSetInformationProcess(,ProcessLdtInformation,,) always returns error)
• wine based Win16->Win32 conversion codes:

BOOL16 WINAPI DestroyWindow16( HWND16 hwnd )
{
    return DestroyWindow( WIN_Handle32(hwnd) );
}

Relay routines from 16-bit to 32-bit are autogenerated by convspec

53  pascal -ret16 DestroyWindow(word) DestroyWindow16

• DOS emulation for Win16
• 16-bit <=> native HANDLE conversion
• Fix compatibility problems, fix compatibility problems

install.inf

When 64-bit Windows detects a 16-bit installer, it has a mechanism to start an alternative installer which is not 16-bit. This program uses it.

WINDOWS directory redirection

Some Win16 programs try to save their settings in %WINDIR%<filename>.ini

In recent Windows, it is not allowed to save to %WINDIR%, so it redirects.

winevdm

winevdm.exe [--app-name app.exe] command line
winevdm.exe CALC.EXE

It can also run DOS executables (DOS emulator-like). You can set the DOS version with the VDMDOSVER environment variable.