Using UFUNC in Microsoft Windows

In Microsoft Windows, ufunc resides in sqrext.dll. You can rebuild sqrext.dll by using any language or tool, as long as you maintain the appropriate calling protocol. The source code for sqrext.dll is included in the shipped package (extufunc.c).

When sqrw.dll and sqrwt.dll are loaded, they look for sqrext.dll in the same directory and for any .dlls that are specified in the SQR Extension section in pssqr.ini. If sqrw.dll and sqrwt.dll find sqrext.dll and the .dlls that are specified in the pssqr.ini file, they make the following calls in all of the .dlls, passing the instance handle (of the calling module) and three function pointers:

void InitSQRExtension (
   HINSTANCE hInstance,
   FARPROC lpfnUFuncRegister, 
   FARPROC lpfnConsole, 
   FARPROC lpfnError
   );