Open32 API enables the migration of Windows applications to OS/2 by providing a subset of the Win32 APIs on OS/2 for source code compatibility. The Open32 API provides an identical interface as the function in the Win32 environment.
In "Open32 Developer API Extensions for OS/2 Warp" Redbook from IBM is clarified that Open32 is not a Win32 API emulation, it is a native OS/2 function that is built on the operating system just like other interface layers like GPI, Presentation Manager, Control Program, etc.
|PMWINX.DLL||Open32 API (a subset of about 800 Windows API's)|
|REGISTRY.DLL||Windows-like registry support. Used by Open32.|
|DAPWSOCK.DLL||Open32 Winsock API|
|USER.DAT||If deleted this file gets re-created when REGISTRY.DLL is invoked.|
|SYSTEM.DAT||If deleted this file gets re-created when REGISTRY.DLL is invoked.|
|WGSS46.DLL||Additions to Open32 used to port Netscape Communicator|
|SYSFONT.DLL||System font dynamic link library.|
- Open32 Programming Guide and Reference
- IBM Redbook
- SG244719 - Open32 Developer API Extensions for OS/2 Warp by Theo Foster, Osamu Takagiwa, Franck Yu