Version 0 of Building Tcl DLL's for Windows

Building Tcl DLL Extensions For Windows

Using Microsoft Visual C++ 6

Create a new win32 dynamic link library project and call it something nice, like tcldemo. This is doing to be our package name too.
Select an 'Empty DLL' on the next dialog.
Before you get going, make sure you have told Visual Studio about the Tcl headers and libraries. To do this, open Tools->Options->Directories and give the Tcl include directory in the includes box and the libraries in the libraries box.
Open up the Porject settings menu item for your new project and go to the C++ tab. Add USE_TCL_STUBS to the list of defined symbols and in the Link tab prepend tclstub83.lib to the list of libraries. (Adust the numerical suffix for your version of tcl).
Now we can write some code. Create a new C++ source file, called tcldemo.cpp and paste in the code below.
Build it. Ignore the whining about MSCVRT conflicts. You now have a DLL in either Debug/Release.
Fire up tclsh or better tkcon from the Debug or Release subdirectory under your project and issue

  load tcldemo.dll Tcldemo
  set tcldemo_version
  package require Tcldemo

You should get 0.1 printed twice!

The code:

 #include <windows.h>
 #include <tcl.h>

 #ifndef DECLSPEC_EXPORT
 #define DECLSPEC_EXPORT __declspec(dllexport)
 #endif // DECLSPEC_EXPORT

 BOOL APIENTRY
 DllMain(HANDLE hModule, DWORD dwReason, LPVOID lpReserved)
 {
     return TRUE;
 }

 EXTERN_C int DECLSPEC_EXPORT
 Tcldemo_Init(Tcl_Interp* interp)
 {
 #ifdef USE_TCL_STUBS
     Tcl_InitStubs(interp, "8.3", 0);
 #endif
     Tcl_Obj *version = Tcl_SetVar2Ex(interp, "tcldemo_version", NULL,
                                      Tcl_NewDoubleObj(0.1), TCL_LEAVE_ERR_MSG);
     if (version == NULL)
         return TCL_ERROR;
     int r = Tcl_PkgProvide(interp, "Tcldemo", Tcl_GetString(version));

     // Call Tcl_CreateObjCommand etc.

     return r;
 }

 EXTERN_C int DECLSPEC_EXPORT
 Tcldemo_SafeInit(Tcl_Interp* interp)
 {
     // We don't need to be specially safe so...
     return Tcldemo_Init(interp);
 }