Modify registry/dde such that they no longer need to be compiled with -DUNICODE. Also no longer use Tcl_WinTCharToUtf/Tcl_WinUtfToTchar but the unicode conversions functions to do WCHAR <=> UTF-8 conversions.

When compiled with Tcl >= 8.7, use the TIP #548 wchar_t functions in stead for registry/dde. 
No need to update the registry/dde version numbers (1.3.3 resp. 1.4.1), because those were recentely bumped already, after the Tcl 8.6.9 release.

2 files changed, 259 insertions, 189 deletions

diff --git a/win/tclWinDde.c b/win/tclWinDde.c
index 27ddfc8..6fa9cc2 100644
--- a/win/tclWinDde.c
+++ b/win/tclWinDde.c
@@ -34,7 +34,7 @@ typedef struct RegisteredInterp {
     struct RegisteredInterp *nextPtr;
 				/* The next interp this application knows
 				 * about. */
-    TCHAR *name;			/* Interpreter's name (malloc-ed). */
+    WCHAR *name;		/* Interpreter's name (malloc-ed). */
     Tcl_Obj *handlerPtr;	/* The server handler command */
     Tcl_Interp *interp;		/* The interpreter attached to this name. */
 } RegisteredInterp;
@@ -81,8 +81,8 @@ static int ddeIsServer = 0;
 
 #define TCL_DDE_VERSION		"1.4.1"
 #define TCL_DDE_PACKAGE_NAME	"dde"
-#define TCL_DDE_SERVICE_NAME	TEXT("TclEval")
-#define TCL_DDE_EXECUTE_RESULT	TEXT("$TCLEVAL$EXECUTE$RESULT")
+#define TCL_DDE_SERVICE_NAME	L"TclEval"
+#define TCL_DDE_EXECUTE_RESULT	L"$TCLEVAL$EXECUTE$RESULT"
 
 #define DDE_FLAG_ASYNC 1
 #define DDE_FLAG_BINARY 2
@@ -99,24 +99,34 @@ static LRESULT CALLBACK	DdeClientWindowProc(HWND hwnd, UINT uMsg,
 static int		DdeCreateClient(DdeEnumServices *es);
 static BOOL CALLBACK	DdeEnumWindowsCallback(HWND hwndTarget,
 			    LPARAM lParam);
-static void		DdeExitProc(ClientData clientData);
+static void		DdeExitProc(void *clientData);
 static int		DdeGetServicesList(Tcl_Interp *interp,
-			    const TCHAR *serviceName, const TCHAR *topicName);
+			    const WCHAR *serviceName, const WCHAR *topicName);
 static HDDEDATA CALLBACK DdeServerProc(UINT uType, UINT uFmt, HCONV hConv,
 			    HSZ ddeTopic, HSZ ddeItem, HDDEDATA hData,
 			    DWORD dwData1, DWORD dwData2);
 static LRESULT		DdeServicesOnAck(HWND hwnd, WPARAM wParam,
 			    LPARAM lParam);
-static void		DeleteProc(ClientData clientData);
+static void		DeleteProc(void *clientData);
 static Tcl_Obj *	ExecuteRemoteObject(RegisteredInterp *riPtr,
 			    Tcl_Obj *ddeObjectPtr);
 static int		MakeDdeConnection(Tcl_Interp *interp,
-			    const TCHAR *name, HCONV *ddeConvPtr);
+			    const WCHAR *name, HCONV *ddeConvPtr);
 static void		SetDdeError(Tcl_Interp *interp);
-static int		DdeObjCmd(ClientData clientData,
+static int		DdeObjCmd(void *clientData,
 			    Tcl_Interp *interp, int objc,
 			    Tcl_Obj *const objv[]);
 
+#if (TCL_MAJOR_VERSION < 9) && (TCL_MINOR_VERSION < 7)
+# if TCL_UTF_MAX > 3
+#   define Tcl_WCharToUtfDString(a,b,c) Tcl_WinTCharToUtf(a,(b)*sizeof(WCHAR),c)
+#   define Tcl_UtfToWCharDString(a,b,c) Tcl_WinUtfToTChar(a,b,c)
+# else
+#   define Tcl_WCharToUtfDString Tcl_UniCharToUtfDString
+#   define Tcl_UtfToWCharDString Tcl_UtfToUniCharDString
+# endif
+#endif
+
 static unsigned char *
 getByteArrayFromObj(
 	Tcl_Obj *objPtr,
@@ -136,8 +146,14 @@ getByteArrayFromObj(
     return result;
 }
 
+#ifdef __cplusplus
+extern "C" {
+#endif
 DLLEXPORT int		Dde_Init(Tcl_Interp *interp);
 DLLEXPORT int		Dde_SafeInit(Tcl_Interp *interp);
+#ifdef __cplusplus
+}
+#endif
 
 /*
  *----------------------------------------------------------------------
@@ -159,13 +175,13 @@ int
 Dde_Init(
     Tcl_Interp *interp)
 {
-    if (!Tcl_InitStubs(interp, "8.1", 0)) {
+    if (!Tcl_InitStubs(interp, "8.5-", 0)) {
 	return TCL_ERROR;
     }
 
     Tcl_CreateObjCommand(interp, "dde", DdeObjCmd, NULL, NULL);
     Tcl_CreateExitHandler(DdeExitProc, NULL);
-    return Tcl_PkgProvide(interp, TCL_DDE_PACKAGE_NAME, TCL_DDE_VERSION);
+    return Tcl_PkgProvideEx(interp, TCL_DDE_PACKAGE_NAME, TCL_DDE_VERSION, NULL);
 }
 
 /*
@@ -235,7 +251,7 @@ Initialize(void)
     if (ddeInstance == 0) {
 	Tcl_MutexLock(&ddeMutex);
 	if (ddeInstance == 0) {
-	    if (DdeInitialize(&ddeInstance, (PFNCALLBACK) DdeServerProc,
+	    if (DdeInitializeW(&ddeInstance, (PFNCALLBACK) DdeServerProc,
 		    CBF_SKIP_REGISTRATIONS | CBF_SKIP_UNREGISTRATIONS
 		    | CBF_FAIL_POKES, 0) != DMLERR_NO_ERROR) {
 		ddeInstance = 0;
@@ -248,7 +264,7 @@ Initialize(void)
 	if ((ddeServiceGlobal == 0) && (nameFound != 0)) {
 	    ddeIsServer = 1;
 	    Tcl_CreateExitHandler(DdeExitProc, NULL);
-	    ddeServiceGlobal = DdeCreateStringHandle(ddeInstance,
+	    ddeServiceGlobal = DdeCreateStringHandleW(ddeInstance,
 		    TCL_DDE_SERVICE_NAME, CP_WINUNICODE);
 	    DdeNameService(ddeInstance, ddeServiceGlobal, 0L, DNS_REGISTER);
 	} else {
@@ -283,10 +299,10 @@ Initialize(void)
  *----------------------------------------------------------------------
  */
 
-static const TCHAR *
+static const WCHAR *
 DdeSetServerName(
     Tcl_Interp *interp,
-    const TCHAR *name, /* The name that will be used to refer to the
+    const WCHAR *name, /* The name that will be used to refer to the
 				 * interpreter in later "send" commands. Must
 				 * be globally unique. */
     int flags,		/* DDE_FLAG_FORCE or 0 */
@@ -296,7 +312,7 @@ DdeSetServerName(
     int suffix, offset;
     RegisteredInterp *riPtr, *prevPtr;
     Tcl_DString dString;
-    const TCHAR *actualName;
+    const WCHAR *actualName;
     Tcl_Obj *srvListPtr = NULL, **srvPtrPtr = NULL;
     int n, srvCount = 0, lastSuffix, r = TCL_OK;
     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
@@ -334,7 +350,7 @@ DdeSetServerName(
 	 * current interp, but it doesn't have a name.
 	 */
 
-	return TEXT("");
+	return L"";
     }
 
     /*
@@ -355,8 +371,8 @@ DdeSetServerName(
 		    &srvPtrPtr);
 	}
 	if (r != TCL_OK) {
-	    Tcl_WinUtfToTChar(Tcl_GetStringResult(interp), -1, &dString);
-	    OutputDebugString((TCHAR *) Tcl_DStringValue(&dString));
+	    Tcl_DStringInit(&dString);
+	    OutputDebugStringW(Tcl_UtfToWCharDString(Tcl_GetString(Tcl_GetObjResult(interp)), -1, &dString));
 	    Tcl_DStringFree(&dString);
 	    return NULL;
 	}
@@ -374,14 +390,14 @@ DdeSetServerName(
 	    lastSuffix = suffix;
 	    if (suffix > 1) {
 		if (suffix == 2) {
-		    Tcl_DStringAppend(&dString, (char *)name, _tcslen(name) * sizeof(TCHAR));
-		    Tcl_DStringAppend(&dString, (char *)TEXT(" #"), 2 * sizeof(TCHAR));
+		    Tcl_DStringAppend(&dString, (char *)name, wcslen(name) * sizeof(WCHAR));
+		    Tcl_DStringAppend(&dString, (char *)L" #", 2 * sizeof(WCHAR));
 		    offset = Tcl_DStringLength(&dString);
-		    Tcl_DStringSetLength(&dString, offset + sizeof(TCHAR) * TCL_INTEGER_SPACE);
-		    actualName = (TCHAR *) Tcl_DStringValue(&dString);
+		    Tcl_DStringSetLength(&dString, offset + sizeof(WCHAR) * TCL_INTEGER_SPACE);
+		    actualName = (WCHAR *) Tcl_DStringValue(&dString);
 		}
-		_sntprintf((TCHAR *) (Tcl_DStringValue(&dString) + offset),
-			TCL_INTEGER_SPACE, TEXT("%d"), suffix);
+		_snwprintf((WCHAR *) (Tcl_DStringValue(&dString) + offset),
+			TCL_INTEGER_SPACE, L"%d", suffix);
 	    }
 
 	    /*
@@ -393,8 +409,9 @@ DdeSetServerName(
 		Tcl_DString ds;
 
 		Tcl_ListObjIndex(interp, srvPtrPtr[n], 1, &namePtr);
-		Tcl_WinUtfToTChar(Tcl_GetString(namePtr), -1, &ds);
-		if (_tcscmp(actualName, (TCHAR *)Tcl_DStringValue(&ds)) == 0) {
+		Tcl_DStringInit(&ds);
+		Tcl_UtfToWCharDString(Tcl_GetString(namePtr), -1, &ds);
+		if (wcscmp(actualName, (WCHAR *)Tcl_DStringValue(&ds)) == 0) {
 		    suffix++;
 		    Tcl_DStringFree(&ds);
 		    break;
@@ -410,14 +427,14 @@ DdeSetServerName(
 
     riPtr = (RegisteredInterp *) Tcl_Alloc(sizeof(RegisteredInterp));
     riPtr->interp = interp;
-    riPtr->name = (TCHAR *) Tcl_Alloc((_tcslen(actualName) + 1) * sizeof(TCHAR));
+    riPtr->name = (WCHAR *) Tcl_Alloc((wcslen(actualName) + 1) * sizeof(WCHAR));
     riPtr->nextPtr = tsdPtr->interpListPtr;
     riPtr->handlerPtr = handlerPtr;
     if (riPtr->handlerPtr != NULL) {
 	Tcl_IncrRefCount(riPtr->handlerPtr);
     }
     tsdPtr->interpListPtr = riPtr;
-    _tcscpy(riPtr->name, actualName);
+    wcscpy(riPtr->name, actualName);
 
     if (Tcl_IsSafe(interp)) {
 	Tcl_ExposeCommand(interp, "dde", "dde");
@@ -489,8 +506,7 @@ DdeGetRegistrationPtr(
 
 static void
 DeleteProc(
-    ClientData clientData)	/* The interp we are deleting passed as
-				 * ClientData. */
+    void *clientData)	/* The interp we are deleting. */
 {
     RegisteredInterp *riPtr = (RegisteredInterp *) clientData;
     RegisteredInterp *searchPtr, *prevPtr;
@@ -627,18 +643,20 @@ DdeServerProc(
     HSZ ddeTopic, HSZ ddeItem,	/* String handles. Transaction-type
 				 * dependent. */
     HDDEDATA hData,		/* DDE data. Transaction-type dependent. */
-    DWORD dwData1, DWORD dwData2)
+    DWORD unused1, DWORD unused2)
 				/* Transaction-dependent data. */
 {
     Tcl_DString dString;
     size_t len;
     DWORD dlen;
-    TCHAR *utilString;
+    WCHAR *utilString;
     Tcl_Obj *ddeObjectPtr;
     HDDEDATA ddeReturn = NULL;
     RegisteredInterp *riPtr;
     Conversation *convPtr, *prevConvPtr;
     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
+    (void)unused1;
+    (void)unused2;
 
     switch(uType) {
     case XTYP_CONNECT:
@@ -647,16 +665,16 @@ DdeServerProc(
 	 * sure we have a valid topic.
 	 */
 
-	len = DdeQueryString(ddeInstance, ddeTopic, NULL, 0, CP_WINUNICODE);
+	len = DdeQueryStringW(ddeInstance, ddeTopic, NULL, 0, CP_WINUNICODE);
 	Tcl_DStringInit(&dString);
-	Tcl_DStringSetLength(&dString, (len + 1) * sizeof(TCHAR) - 1);
-	utilString = (TCHAR *) Tcl_DStringValue(&dString);
-	DdeQueryString(ddeInstance, ddeTopic, utilString, (DWORD) len + 1,
+	Tcl_DStringSetLength(&dString, (len + 1) * sizeof(WCHAR) - 1);
+	utilString = (WCHAR *) Tcl_DStringValue(&dString);
+	DdeQueryStringW(ddeInstance, ddeTopic, utilString, (DWORD) len + 1,
 		CP_WINUNICODE);
 
 	for (riPtr = tsdPtr->interpListPtr; riPtr != NULL;
 		riPtr = riPtr->nextPtr) {
-	    if (_tcsicmp(utilString, riPtr->name) == 0) {
+	    if (_wcsicmp(utilString, riPtr->name) == 0) {
 		Tcl_DStringFree(&dString);
 		return (HDDEDATA) TRUE;
 	    }
@@ -672,15 +690,15 @@ DdeServerProc(
 	 * result to return in an XTYP_REQUEST.
 	 */
 
-	len = DdeQueryString(ddeInstance, ddeTopic, NULL, 0, CP_WINUNICODE);
+	len = DdeQueryStringW(ddeInstance, ddeTopic, NULL, 0, CP_WINUNICODE);
 	Tcl_DStringInit(&dString);
-	Tcl_DStringSetLength(&dString,  (len + 1) * sizeof(TCHAR) - 1);
-	utilString = (TCHAR *) Tcl_DStringValue(&dString);
-	DdeQueryString(ddeInstance, ddeTopic, utilString, (DWORD) len + 1,
+	Tcl_DStringSetLength(&dString,  (len + 1) * sizeof(WCHAR) - 1);
+	utilString = (WCHAR *) Tcl_DStringValue(&dString);
+	DdeQueryStringW(ddeInstance, ddeTopic, utilString, (DWORD) len + 1,
 		CP_WINUNICODE);
 	for (riPtr = tsdPtr->interpListPtr; riPtr != NULL;
 		riPtr = riPtr->nextPtr) {
-	    if (_tcsicmp(riPtr->name, utilString) == 0) {
+	    if (_wcsicmp(riPtr->name, utilString) == 0) {
 		convPtr = (Conversation *) Tcl_Alloc(sizeof(Conversation));
 		convPtr->nextPtr = tsdPtr->currentConversations;
 		convPtr->returnPackagePtr = NULL;
@@ -740,21 +758,22 @@ DdeServerProc(
 	    Tcl_DString dsBuf;
 	    char *returnString;
 
-	    len = DdeQueryString(ddeInstance, ddeItem, NULL, 0, CP_WINUNICODE);
+	    len = DdeQueryStringW(ddeInstance, ddeItem, NULL, 0, CP_WINUNICODE);
 	    Tcl_DStringInit(&dString);
 	    Tcl_DStringInit(&dsBuf);
-	    Tcl_DStringSetLength(&dString, (len + 1) * sizeof(TCHAR) - 1);
-	    utilString = (TCHAR *) Tcl_DStringValue(&dString);
-	    DdeQueryString(ddeInstance, ddeItem, utilString, (DWORD) len + 1,
+	    Tcl_DStringSetLength(&dString, (len + 1) * sizeof(WCHAR) - 1);
+	    utilString = (WCHAR *) Tcl_DStringValue(&dString);
+	    DdeQueryStringW(ddeInstance, ddeItem, utilString, (DWORD) len + 1,
 		    CP_WINUNICODE);
-	    if (_tcsicmp(utilString, TCL_DDE_EXECUTE_RESULT) == 0) {
+	    if (_wcsicmp(utilString, TCL_DDE_EXECUTE_RESULT) == 0) {
 		returnString =
 			Tcl_GetString(convPtr->returnPackagePtr);
 		len = convPtr->returnPackagePtr->length;
 		if (uFmt != CF_TEXT) {
-		    Tcl_WinUtfToTChar(returnString, len, &dsBuf);
+		    Tcl_DStringInit(&dsBuf);
+		    Tcl_UtfToWCharDString(returnString, len, &dsBuf);
 		    returnString = Tcl_DStringValue(&dsBuf);
-		    len = Tcl_DStringLength(&dsBuf) + sizeof(TCHAR) - 1;
+		    len = Tcl_DStringLength(&dsBuf) + sizeof(WCHAR) - 1;
 		}
 		ddeReturn = DdeCreateDataHandle(ddeInstance, (BYTE *)returnString,
 			(DWORD) len+1, 0, ddeItem, uFmt, 0);
@@ -765,7 +784,8 @@ DdeServerProc(
 		    Tcl_DString ds;
 		    Tcl_Obj *variableObjPtr;
 
-		    Tcl_WinTCharToUtf(utilString, -1, &ds);
+		    Tcl_DStringInit(&ds);
+		    Tcl_WCharToUtfDString(utilString, wcslen(utilString), &ds);
 		    variableObjPtr = Tcl_GetVar2Ex(
 			    convPtr->riPtr->interp, Tcl_DStringValue(&ds), NULL,
 			    TCL_GLOBAL_ONLY);
@@ -773,9 +793,10 @@ DdeServerProc(
 			returnString = Tcl_GetString(variableObjPtr);
 			len = variableObjPtr->length;
 			if (uFmt != CF_TEXT) {
-			    Tcl_WinUtfToTChar(returnString, len, &dsBuf);
+			    Tcl_DStringInit(&dsBuf);
+			    Tcl_UtfToWCharDString(returnString, len, &dsBuf);
 			    returnString = Tcl_DStringValue(&dsBuf);
-			    len = Tcl_DStringLength(&dsBuf) + sizeof(TCHAR) - 1;
+			    len = Tcl_DStringLength(&dsBuf) + sizeof(WCHAR) - 1;
 			}
 			ddeReturn = DdeCreateDataHandle(ddeInstance,
 				(BYTE *)returnString, (DWORD) len+1, 0, ddeItem,
@@ -817,17 +838,19 @@ DdeServerProc(
 
 	    Tcl_DStringInit(&dString);
 	    Tcl_DStringInit(&ds2);
-	    len = DdeQueryString(ddeInstance, ddeItem, NULL, 0, CP_WINUNICODE);
-	    Tcl_DStringSetLength(&dString, (len + 1) * sizeof(TCHAR) - 1);
-	    utilString = (TCHAR *) Tcl_DStringValue(&dString);
-	    DdeQueryString(ddeInstance, ddeItem, utilString, (DWORD) len + 1,
+	    len = DdeQueryStringW(ddeInstance, ddeItem, NULL, 0, CP_WINUNICODE);
+	    Tcl_DStringSetLength(&dString, (len + 1) * sizeof(WCHAR) - 1);
+	    utilString = (WCHAR *) Tcl_DStringValue(&dString);
+	    DdeQueryStringW(ddeInstance, ddeItem, utilString, (DWORD) len + 1,
 		    CP_WINUNICODE);
-	    Tcl_WinTCharToUtf(utilString, -1, &ds);
-	    utilString = (TCHAR *) DdeAccessData(hData, &len2);
+	    Tcl_DStringInit(&ds);
+	    Tcl_WCharToUtfDString(utilString, wcslen(utilString), &ds);
+	    utilString = (WCHAR *) DdeAccessData(hData, &len2);
 	    len = len2;
 	    if (uFmt != CF_TEXT) {
-		Tcl_WinTCharToUtf(utilString, -1, &ds2);
-		utilString = (TCHAR *) Tcl_DStringValue(&ds2);
+		Tcl_DStringInit(&ds2);
+		Tcl_WCharToUtfDString(utilString, wcslen(utilString), &ds2);
+		utilString = (WCHAR *) Tcl_DStringValue(&ds2);
 	    }
 	    variableObjPtr = Tcl_NewStringObj((char *)utilString, -1);
 
@@ -862,7 +885,7 @@ DdeServerProc(
 	    return (HDDEDATA) DDE_FNOTPROCESSED;
 	}
 
-	utilString = (TCHAR *) DdeAccessData(hData, &dlen);
+	utilString = (WCHAR *) DdeAccessData(hData, &dlen);
 	string = (char *) utilString;
 	if (!dlen) {
 	    /* Empty binary array. */
@@ -877,7 +900,8 @@ DdeServerProc(
 	    /* unicode */
 	    Tcl_DString dsBuf;
 
-	    Tcl_WinTCharToUtf(utilString, dlen - sizeof(TCHAR), &dsBuf);
+	    Tcl_DStringInit(&dsBuf);
+	    Tcl_WCharToUtfDString(utilString, (dlen>>1) - 1, &dsBuf);
 	    ddeObjectPtr = Tcl_NewStringObj(Tcl_DStringValue(&dsBuf),
 		    Tcl_DStringLength(&dsBuf));
 	    Tcl_DStringFree(&dsBuf);
@@ -932,9 +956,9 @@ DdeServerProc(
 	len = dlen;
 	for (i = 0, riPtr = tsdPtr->interpListPtr; i < numItems;
 		i++, riPtr = riPtr->nextPtr) {
-	    returnPtr[i].hszSvc = DdeCreateStringHandle(ddeInstance,
+	    returnPtr[i].hszSvc = DdeCreateStringHandleW(ddeInstance,
 		    TCL_DDE_SERVICE_NAME, CP_WINUNICODE);
-	    returnPtr[i].hszTopic = DdeCreateStringHandle(ddeInstance,
+	    returnPtr[i].hszTopic = DdeCreateStringHandleW(ddeInstance,
 		    riPtr->name, CP_WINUNICODE);
 	}
 	returnPtr[i].hszSvc = NULL;
@@ -966,8 +990,9 @@ DdeServerProc(
 
 static void
 DdeExitProc(
-    ClientData clientData)	    /* Not used in this handler. */
+    void *dummy)		/* Not used. */
 {
+    (void)dummy;
     DdeNameService(ddeInstance, NULL, 0, DNS_UNREGISTER);
     DdeUninitialize(ddeInstance);
     ddeInstance = 0;
@@ -993,14 +1018,14 @@ DdeExitProc(
 static int
 MakeDdeConnection(
     Tcl_Interp *interp,		/* Used to report errors. */
-    const TCHAR *name,		/* The connection to use. */
+    const WCHAR *name,		/* The connection to use. */
     HCONV *ddeConvPtr)
 {
     HSZ ddeTopic, ddeService;
     HCONV ddeConv;
 
-    ddeService = DdeCreateStringHandle(ddeInstance, TCL_DDE_SERVICE_NAME, CP_WINUNICODE);
-    ddeTopic = DdeCreateStringHandle(ddeInstance, name, CP_WINUNICODE);
+    ddeService = DdeCreateStringHandleW(ddeInstance, TCL_DDE_SERVICE_NAME, CP_WINUNICODE);
+    ddeTopic = DdeCreateStringHandleW(ddeInstance, name, CP_WINUNICODE);
 
     ddeConv = DdeConnect(ddeInstance, ddeService, ddeTopic, NULL);
     DdeFreeStringHandle(ddeInstance, ddeService);
@@ -1010,7 +1035,8 @@ MakeDdeConnection(
 	if (interp != NULL) {
 	    Tcl_DString dString;
 
-	    Tcl_WinTCharToUtf(name, -1, &dString);
+	    Tcl_DStringInit(&dString);
+	    Tcl_WCharToUtfDString(name, wcslen(name), &dString);
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		    "no registered server named \"%s\"", Tcl_DStringValue(&dString)));
 	    Tcl_DStringFree(&dString);
@@ -1047,9 +1073,9 @@ static int
 DdeCreateClient(
     DdeEnumServices *es)
 {
-    WNDCLASSEX wc;
-    static const TCHAR *szDdeClientClassName = TEXT("TclEval client class");
-    static const TCHAR *szDdeClientWindowName = TEXT("TclEval client window");
+    WNDCLASSEXW wc;
+    static const WCHAR *szDdeClientClassName = L"TclEval client class";
+    static const WCHAR *szDdeClientWindowName = L"TclEval client window";
 
     memset(&wc, 0, sizeof(wc));
     wc.cbSize = sizeof(wc);
@@ -1061,8 +1087,8 @@ DdeCreateClient(
      * Register and create the callback window.
      */
 
-    RegisterClassEx(&wc);
-    es->hwnd = CreateWindowEx(0, szDdeClientClassName, szDdeClientWindowName,
+    RegisterClassExW(&wc);
+    es->hwnd = CreateWindowExW(0, szDdeClientClassName, szDdeClientWindowName,
 	    WS_POPUP, 0, 0, 0, 0, NULL, NULL, NULL, (LPVOID)es);
     return TCL_OK;
 }
@@ -1081,16 +1107,16 @@ DdeClientWindowProc(
 		(DdeEnumServices *) lpcs->lpCreateParams;
 
 #ifdef _WIN64
-	SetWindowLongPtr(hwnd, GWLP_USERDATA, (LONG_PTR) es);
+	SetWindowLongPtrW(hwnd, GWLP_USERDATA, (LONG_PTR) es);
 #else
-	SetWindowLong(hwnd, GWL_USERDATA, (LONG) es);
+	SetWindowLongW(hwnd, GWL_USERDATA, (LONG) es);
 #endif
 	return (LRESULT) 0L;
     }
     case WM_DDE_ACK:
 	return DdeServicesOnAck(hwnd, wParam, lParam);
     default:
-	return DefWindowProc(hwnd, uMsg, wParam, lParam);
+	return DefWindowProcW(hwnd, uMsg, wParam, lParam);
     }
 }
 
@@ -1104,13 +1130,13 @@ DdeServicesOnAck(
     ATOM service = (ATOM)LOWORD(lParam);
     ATOM topic = (ATOM)HIWORD(lParam);
     DdeEnumServices *es;
-    TCHAR sz[255];
+    WCHAR sz[255];
     Tcl_DString dString;
 
 #ifdef _WIN64
-    es = (DdeEnumServices *) GetWindowLongPtr(hwnd, GWLP_USERDATA);
+    es = (DdeEnumServices *) GetWindowLongPtrW(hwnd, GWLP_USERDATA);
 #else
-    es = (DdeEnumServices *) GetWindowLong(hwnd, GWL_USERDATA);
+    es = (DdeEnumServices *) GetWindowLongW(hwnd, GWL_USERDATA);
 #endif
 
     if (((es->service == (ATOM)0) || (es->service == service))
@@ -1118,12 +1144,14 @@ DdeServicesOnAck(
 	Tcl_Obj *matchPtr = Tcl_NewListObj(0, NULL);
 	Tcl_Obj *resultPtr = Tcl_GetObjResult(es->interp);
 
-	GlobalGetAtomName(service, sz, 255);
-	Tcl_WinTCharToUtf(sz, -1, &dString);
+	GlobalGetAtomNameW(service, sz, 255);
+	Tcl_DStringInit(&dString);
+	Tcl_WCharToUtfDString(sz, wcslen(sz), &dString);
 	Tcl_ListObjAppendElement(NULL, matchPtr, Tcl_NewStringObj(Tcl_DStringValue(&dString), -1));
 	Tcl_DStringFree(&dString);
-	GlobalGetAtomName(topic, sz, 255);
-	Tcl_WinTCharToUtf(sz, -1, &dString);
+	GlobalGetAtomNameW(topic, sz, 255);
+	Tcl_DStringInit(&dString);
+	Tcl_WCharToUtfDString(sz, wcslen(sz), &dString);
 	Tcl_ListObjAppendElement(NULL, matchPtr, Tcl_NewStringObj(Tcl_DStringValue(&dString), -1));
 	Tcl_DStringFree(&dString);
 
@@ -1151,7 +1179,7 @@ DdeServicesOnAck(
      * Tell the server we are no longer interested.
      */
 
-    PostMessage(hwndRemote, WM_DDE_TERMINATE, (WPARAM)hwnd, 0L);
+    PostMessageW(hwndRemote, WM_DDE_TERMINATE, (WPARAM)hwnd, 0L);
     return 0L;
 }
 
@@ -1163,7 +1191,7 @@ DdeEnumWindowsCallback(
     DWORD_PTR dwResult = 0;
     DdeEnumServices *es = (DdeEnumServices *) lParam;
 
-    SendMessageTimeout(hwndTarget, WM_DDE_INITIATE, (WPARAM)es->hwnd,
+    SendMessageTimeoutW(hwndTarget, WM_DDE_INITIATE, (WPARAM)es->hwnd,
 	    MAKELONG(es->service, es->topic), SMTO_ABORTIFHUNG, 1000,
 	    &dwResult);
     return TRUE;
@@ -1172,16 +1200,16 @@ DdeEnumWindowsCallback(
 static int
 DdeGetServicesList(
     Tcl_Interp *interp,
-    const TCHAR *serviceName,
-    const TCHAR *topicName)
+    const WCHAR *serviceName,
+    const WCHAR *topicName)
 {
     DdeEnumServices es;
 
     es.interp = interp;
     es.result = TCL_OK;
     es.service = (serviceName == NULL)
-	    ? (ATOM)0 : GlobalAddAtom(serviceName);
-    es.topic = (topicName == NULL) ? (ATOM)0 : GlobalAddAtom(topicName);
+	    ? (ATOM)0 : GlobalAddAtomW(serviceName);
+    es.topic = (topicName == NULL) ? (ATOM)0 : GlobalAddAtomW(topicName);
 
     Tcl_ResetResult(interp); /* our list is to be appended to result. */
     DdeCreateClient(&es);
@@ -1265,7 +1293,7 @@ SetDdeError(
 
 static int
 DdeObjCmd(
-    ClientData clientData,	/* Used only for deletion */
+    void *dummy,	/* Not used. */
     Tcl_Interp *interp,		/* The interp we are sending from */
     int objc,			/* Number of arguments */
     Tcl_Obj *const *objv)	/* The arguments */
@@ -1302,11 +1330,12 @@ DdeObjCmd(
     HSZ ddeService = NULL, ddeTopic = NULL, ddeItem = NULL, ddeCookie = NULL;
     HDDEDATA ddeData = NULL, ddeItemData = NULL, ddeReturn;
     HCONV hConv = NULL;
-    const TCHAR *serviceName = NULL, *topicName = NULL;
+    const WCHAR *serviceName = NULL, *topicName = NULL;
     const char *string;
     DWORD ddeResult;
     Tcl_Obj *objPtr, *handlerPtr = NULL;
     Tcl_DString serviceBuf, topicBuf, itemBuf;
+    (void)dummy;
 
     /*
      * Initialize DDE server/client
@@ -1462,9 +1491,10 @@ DdeObjCmd(
 	const char *src = Tcl_GetString(objv[firstArg]);
 
 	length = objv[firstArg]->length;
-	Tcl_WinUtfToTChar(src, length, &serviceBuf);
-	serviceName = (TCHAR *) Tcl_DStringValue(&serviceBuf);
-	length = Tcl_DStringLength(&serviceBuf) / sizeof(TCHAR);
+	Tcl_DStringInit(&serviceBuf);
+	Tcl_UtfToWCharDString(src, length, &serviceBuf);
+	serviceName = (WCHAR *) Tcl_DStringValue(&serviceBuf);
+	length = Tcl_DStringLength(&serviceBuf) / sizeof(WCHAR);
     } else {
 	length = 0;
     }
@@ -1472,7 +1502,7 @@ DdeObjCmd(
     if (length == 0) {
 	serviceName = NULL;
     } else if ((index != DDE_SERVERNAME) && (index != DDE_EVAL)) {
-	ddeService = DdeCreateStringHandle(ddeInstance, (void *) serviceName,
+	ddeService = DdeCreateStringHandleW(ddeInstance, serviceName,
 		CP_WINUNICODE);
     }
 
@@ -1480,12 +1510,13 @@ DdeObjCmd(
 	const char *src = Tcl_GetString(objv[firstArg + 1]);
 
 	length = objv[firstArg + 1]->length;
-	topicName = Tcl_WinUtfToTChar(src, length, &topicBuf);
-	length = Tcl_DStringLength(&topicBuf) / sizeof(TCHAR);
+	Tcl_DStringInit(&topicBuf);
+	topicName = Tcl_UtfToWCharDString(src, length, &topicBuf);
+	length = Tcl_DStringLength(&topicBuf) / sizeof(WCHAR);
 	if (length == 0) {
 	    topicName = NULL;
 	} else {
-	    ddeTopic = DdeCreateStringHandle(ddeInstance, (void *) topicName,
+	    ddeTopic = DdeCreateStringHandleW(ddeInstance, topicName,
 		    CP_WINUNICODE);
 	}
     }
@@ -1497,7 +1528,8 @@ DdeObjCmd(
 	if (serviceName != NULL) {
 	    Tcl_DString dsBuf;
 
-	    Tcl_WinTCharToUtf(serviceName, -1, &dsBuf);
+	    Tcl_DStringInit(&dsBuf);
+	    Tcl_WCharToUtfDString(serviceName, wcslen(serviceName), &dsBuf);
 	    Tcl_SetObjResult(interp, Tcl_NewStringObj(Tcl_DStringValue(&dsBuf),
 		    Tcl_DStringLength(&dsBuf)));
 	    Tcl_DStringFree(&dsBuf);
@@ -1520,9 +1552,10 @@ DdeObjCmd(
 
 	    src = Tcl_GetString(objv[firstArg + 2]);
 	    dataLength = objv[firstArg + 2]->length;
-	    dataString = (const TCHAR *)
-		    Tcl_WinUtfToTChar(src, dataLength, &dsBuf);
-	    dataLength = Tcl_DStringLength(&dsBuf) + sizeof(TCHAR);
+	    Tcl_DStringInit(&dsBuf);
+	    dataString =
+		    Tcl_UtfToWCharDString(src, dataLength, &dsBuf);
+	    dataLength = Tcl_DStringLength(&dsBuf) + sizeof(WCHAR);
 	}
 
 	if (dataLength + 1 < 2) {
@@ -1568,13 +1601,14 @@ DdeObjCmd(
 	break;
     }
     case DDE_REQUEST: {
-	const TCHAR *itemString;
+	const WCHAR *itemString;
 	const char *src;
 
 	src = Tcl_GetString(objv[firstArg + 2]);
 	length = objv[firstArg + 2]->length;
-	itemString = Tcl_WinUtfToTChar(src, length, &itemBuf);
-	length = Tcl_DStringLength(&itemBuf) / sizeof(TCHAR);
+	Tcl_DStringInit(&itemBuf);
+	itemString = Tcl_UtfToWCharDString(src, length, &itemBuf);
+	length = Tcl_DStringLength(&itemBuf) / sizeof(WCHAR);
 
 	if (length == 0) {
 	    Tcl_SetObjResult(interp,
@@ -1592,7 +1626,7 @@ DdeObjCmd(
 	    result = TCL_ERROR;
 	} else {
 	    Tcl_Obj *returnObjPtr;
-	    ddeItem = DdeCreateStringHandle(ddeInstance, (void *) itemString,
+	    ddeItem = DdeCreateStringHandleW(ddeInstance, itemString,
 		    CP_WINUNICODE);
 	    if (ddeItem != NULL) {
 		ddeData = DdeClientTransaction(NULL, 0, hConv, ddeItem,
@@ -1602,7 +1636,7 @@ DdeObjCmd(
 		    result = TCL_ERROR;
 		} else {
 		    DWORD tmp;
-		    TCHAR *dataString = (TCHAR *) DdeAccessData(ddeData, &tmp);
+		    WCHAR *dataString = (WCHAR *) DdeAccessData(ddeData, &tmp);
 
 		    if (flags & DDE_FLAG_BINARY) {
 			returnObjPtr =
@@ -1610,11 +1644,12 @@ DdeObjCmd(
 		    } else {
 			Tcl_DString dsBuf;
 
-			if ((tmp >= sizeof(TCHAR))
-				&& !dataString[tmp / sizeof(TCHAR) - 1]) {
-			    tmp -= sizeof(TCHAR);
+			if ((tmp >= sizeof(WCHAR))
+				&& !dataString[tmp / sizeof(WCHAR) - 1]) {
+			    tmp -= sizeof(WCHAR);
 			}
-			Tcl_WinTCharToUtf(dataString, tmp, &dsBuf);
+			Tcl_DStringInit(&dsBuf);
+			Tcl_WCharToUtfDString(dataString, tmp>>1, &dsBuf);
 			returnObjPtr =
 			    Tcl_NewStringObj(Tcl_DStringValue(&dsBuf),
 				    Tcl_DStringLength(&dsBuf));
@@ -1633,14 +1668,15 @@ DdeObjCmd(
     }
     case DDE_POKE: {
 	Tcl_DString dsBuf;
-	const TCHAR *itemString;
+	const WCHAR *itemString;
 	BYTE *dataString;
 	const char *src;
 
 	src = Tcl_GetString(objv[firstArg + 2]);
 	length = objv[firstArg + 2]->length;
-	itemString = Tcl_WinUtfToTChar(src, length, &itemBuf);
-	length = Tcl_DStringLength(&itemBuf) / sizeof(TCHAR);
+	Tcl_DStringInit(&itemBuf);
+	itemString = Tcl_UtfToWCharDString(src, length, &itemBuf);
+	length = Tcl_DStringLength(&itemBuf) / sizeof(WCHAR);
 	if (length == 0) {
 	    Tcl_SetObjResult(interp,
 		    Tcl_NewStringObj("cannot have a null item", -1));
@@ -1656,9 +1692,10 @@ DdeObjCmd(
 	    const char *data =
 		    Tcl_GetString(objv[firstArg + 3]);
 	    length = objv[firstArg + 3]->length;
+	    Tcl_DStringInit(&dsBuf);
 	    dataString = (BYTE *)
-		    Tcl_WinUtfToTChar(data, length, &dsBuf);
-	    length = Tcl_DStringLength(&dsBuf) + sizeof(TCHAR);
+		    Tcl_UtfToWCharDString(data, length, &dsBuf);
+	    length = Tcl_DStringLength(&dsBuf) + sizeof(WCHAR);
 	}
 
 	hConv = DdeConnect(ddeInstance, ddeService, ddeTopic, NULL);
@@ -1669,7 +1706,7 @@ DdeObjCmd(
 	    SetDdeError(interp);
 	    result = TCL_ERROR;
 	} else {
-	    ddeItem = DdeCreateStringHandle(ddeInstance, (void *) itemString,
+	    ddeItem = DdeCreateStringHandleW(ddeInstance, itemString,
 		    CP_WINUNICODE);
 	    if (ddeItem != NULL) {
 		ddeData = DdeClientTransaction(dataString, (DWORD) length,
@@ -1717,7 +1754,7 @@ DdeObjCmd(
 
 	for (riPtr = tsdPtr->interpListPtr; riPtr != NULL;
 		riPtr = riPtr->nextPtr) {
-	    if (_tcsicmp(serviceName, riPtr->name) == 0) {
+	    if (_wcsicmp(serviceName, riPtr->name) == 0) {
 		break;
 	    }
 	}
@@ -1820,9 +1857,10 @@ DdeObjCmd(
 	    objPtr = Tcl_ConcatObj(objc, objv);
 	    string = Tcl_GetString(objPtr);
 	    length = objPtr->length;
-	    Tcl_WinUtfToTChar(string, length, &dsBuf);
+	    Tcl_DStringInit(&dsBuf);
+	    Tcl_UtfToWCharDString(string, length, &dsBuf);
 	    string = Tcl_DStringValue(&dsBuf);
-	    length = Tcl_DStringLength(&dsBuf) + sizeof(TCHAR);
+	    length = Tcl_DStringLength(&dsBuf) + sizeof(WCHAR);
 	    ddeItemData = DdeCreateDataHandle(ddeInstance, (BYTE *) string,
 		    (DWORD) length, 0, 0, CF_UNICODETEXT, 0);
 	    Tcl_DStringFree(&dsBuf);
@@ -1837,7 +1875,7 @@ DdeObjCmd(
 			0xFFFFFFFF, hConv, 0,
 			CF_UNICODETEXT, XTYP_EXECUTE, 30000, NULL);
 		if (ddeData != 0) {
-		    ddeCookie = DdeCreateStringHandle(ddeInstance,
+		    ddeCookie = DdeCreateStringHandleW(ddeInstance,
 			    TCL_DDE_EXECUTE_RESULT, CP_WINUNICODE);
 		    ddeData = DdeClientTransaction(NULL, 0, hConv, ddeCookie,
 			    CF_UNICODETEXT, XTYP_REQUEST, 30000, NULL);
@@ -1854,7 +1892,7 @@ DdeObjCmd(
 
 	    if (!(flags & DDE_FLAG_ASYNC)) {
 		Tcl_Obj *resultPtr;
-		TCHAR *ddeDataString;
+		WCHAR *ddeDataString;
 
 		/*
 		 * The return handle has a two or four element list in it. The
@@ -1866,12 +1904,13 @@ DdeObjCmd(
 		 */
 
 		length = DdeGetData(ddeData, NULL, 0, 0);
-		ddeDataString = (TCHAR *) Tcl_Alloc(length);
+		ddeDataString = (WCHAR *) Tcl_Alloc(length);
 		DdeGetData(ddeData, (BYTE *) ddeDataString, (DWORD) length, 0);
-		if (length > sizeof(TCHAR)) {
-		    length -= sizeof(TCHAR);
+		if (length > sizeof(WCHAR)) {
+		    length -= sizeof(WCHAR);
 		}
-		Tcl_WinTCharToUtf(ddeDataString, length, &dsBuf);
+		Tcl_DStringInit(&dsBuf);
+		Tcl_WCharToUtfDString(ddeDataString, length>>1, &dsBuf);
 		resultPtr = Tcl_NewStringObj(Tcl_DStringValue(&dsBuf),
 			Tcl_DStringLength(&dsBuf));
 		Tcl_DStringFree(&dsBuf);
diff --git a/win/tclWinReg.c b/win/tclWinReg.c
index f93a553..068e5d7 100644
--- a/win/tclWinReg.c
+++ b/win/tclWinReg.c
@@ -94,7 +94,7 @@ static void		AppendSystemError(Tcl_Interp *interp, DWORD error);
 static int		BroadcastValue(Tcl_Interp *interp, int objc,
 			    Tcl_Obj *const objv[]);
 static DWORD		ConvertDWORD(DWORD type, DWORD value);
-static void		DeleteCmd(ClientData clientData);
+static void		DeleteCmd(void *clientData);
 static int		DeleteKey(Tcl_Interp *interp, Tcl_Obj *keyNameObj,
 			    REGSAM mode);
 static int		DeleteValue(Tcl_Interp *interp, Tcl_Obj *keyNameObj,
@@ -116,14 +116,24 @@ static int		ParseKeyName(Tcl_Interp *interp, char *name,
 			    char **hostNamePtr, HKEY *rootKeyPtr,
 			    char **keyNamePtr);
 static DWORD		RecursiveDeleteKey(HKEY hStartKey,
-			    const TCHAR * pKeyName, REGSAM mode);
-static int		RegistryObjCmd(ClientData clientData,
+			    const WCHAR * pKeyName, REGSAM mode);
+static int		RegistryObjCmd(void *clientData,
 			    Tcl_Interp *interp, int objc,
 			    Tcl_Obj *const objv[]);
 static int		SetValue(Tcl_Interp *interp, Tcl_Obj *keyNameObj,
 			    Tcl_Obj *valueNameObj, Tcl_Obj *dataObj,
 			    Tcl_Obj *typeObj, REGSAM mode);
 
+#if (TCL_MAJOR_VERSION < 9) && (TCL_MINOR_VERSION < 7)
+# if TCL_UTF_MAX > 3
+#   define Tcl_WCharToUtfDString(a,b,c) Tcl_WinTCharToUtf(a,(b)*sizeof(WCHAR),c)
+#   define Tcl_UtfToWCharDString(a,b,c) Tcl_WinUtfToTChar(a,b,c)
+# else
+#   define Tcl_WCharToUtfDString Tcl_UniCharToUtfDString
+#   define Tcl_UtfToWCharDString Tcl_UtfToUniCharDString
+# endif
+#endif
+
 static unsigned char *
 getByteArrayFromObj(
 	Tcl_Obj *objPtr,
@@ -143,8 +153,14 @@ getByteArrayFromObj(
     return result;
 }
 
+#ifdef __cplusplus
+extern "C" {
+#endif
 DLLEXPORT int		Registry_Init(Tcl_Interp *interp);
 DLLEXPORT int		Registry_Unload(Tcl_Interp *interp, int flags);
+#ifdef __cplusplus
+}
+#endif
 
 /*
  *----------------------------------------------------------------------
@@ -168,14 +184,14 @@ Registry_Init(
 {
     Tcl_Command cmd;
 
-    if (Tcl_InitStubs(interp, "8.5", 0) == NULL) {
+    if (Tcl_InitStubs(interp, "8.5-", 0) == NULL) {
 	return TCL_ERROR;
     }
 
     cmd = Tcl_CreateObjCommand(interp, "registry", RegistryObjCmd,
 	    interp, DeleteCmd);
     Tcl_SetAssocData(interp, REGISTRY_ASSOC_KEY, NULL, cmd);
-    return Tcl_PkgProvide(interp, "registry", "1.3.3");
+    return Tcl_PkgProvideEx(interp, "registry", "1.3.3", NULL);
 }
 
 /*
@@ -201,6 +217,7 @@ Registry_Unload(
 {
     Tcl_Command cmd;
     Tcl_Obj *objv[3];
+    (void)flags;
 
     /*
      * Unregister the registry package. There is no Tcl_PkgForget()
@@ -215,7 +232,7 @@ Registry_Unload(
      * Delete the originally registered command.
      */
 
-    cmd = Tcl_GetAssocData(interp, REGISTRY_ASSOC_KEY, NULL);
+    cmd = (Tcl_Command)Tcl_GetAssocData(interp, REGISTRY_ASSOC_KEY, NULL);
     if (cmd != NULL) {
 	Tcl_DeleteCommandFromToken(interp, cmd);
     }
@@ -242,9 +259,9 @@ Registry_Unload(
 
 static void
 DeleteCmd(
-    ClientData clientData)
+    void *clientData)
 {
-    Tcl_Interp *interp = clientData;
+    Tcl_Interp *interp = (Tcl_Interp *)clientData;
 
     Tcl_SetAssocData(interp, REGISTRY_ASSOC_KEY, NULL, NULL);
 }
@@ -267,7 +284,7 @@ DeleteCmd(
 
 static int
 RegistryObjCmd(
-    ClientData clientData,	/* Not used. */
+    void *dummy,	/* Not used. */
     Tcl_Interp *interp,		/* Current interpreter. */
     int objc,			/* Number of arguments. */
     Tcl_Obj *const objv[])	/* Argument values. */
@@ -286,6 +303,7 @@ RegistryObjCmd(
     static const char *const modes[] = {
 	"-32bit", "-64bit", NULL
     };
+    (void)dummy;
 
     if (objc < 2) {
     wrongArgs:
@@ -415,7 +433,7 @@ DeleteKey(
     REGSAM mode)		/* Mode flags to pass. */
 {
     char *tail, *buffer, *hostName, *keyName;
-    const TCHAR *nativeTail;
+    const WCHAR *nativeTail;
     HKEY rootKey, subkey;
     DWORD result;
     Tcl_DString buf;
@@ -468,7 +486,8 @@ DeleteKey(
      * Now we recursively delete the key and everything below it.
      */
 
-    nativeTail = Tcl_WinUtfToTChar(tail, -1, &buf);
+    Tcl_DStringInit(&buf);
+    nativeTail = Tcl_UtfToWCharDString(tail, -1, &buf);
     result = RecursiveDeleteKey(subkey, nativeTail, saveMode);
     Tcl_DStringFree(&buf);
 
@@ -524,8 +543,9 @@ DeleteValue(
     }
 
     valueName = Tcl_GetString(valueNameObj);
-    Tcl_WinUtfToTChar(valueName, valueNameObj->length, &ds);
-    result = RegDeleteValue(key, (const TCHAR *)Tcl_DStringValue(&ds));
+    Tcl_DStringInit(&ds);
+    Tcl_UtfToWCharDString(valueName, valueNameObj->length, &ds);
+    result = RegDeleteValueW(key, (const WCHAR *)Tcl_DStringValue(&ds));
     Tcl_DStringFree(&ds);
     if (result != ERROR_SUCCESS) {
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
@@ -568,7 +588,7 @@ GetKeyNames(
 {
     const char *pattern;	/* Pattern being matched against subkeys */
     HKEY key;			/* Handle to the key being examined */
-    TCHAR buffer[MAX_KEY_LENGTH];
+    WCHAR buffer[MAX_KEY_LENGTH];
 				/* Buffer to hold the subkey name */
     DWORD bufSize;		/* Size of the buffer */
     DWORD index;		/* Position of the current subkey */
@@ -599,7 +619,7 @@ GetKeyNames(
     resultPtr = Tcl_NewObj();
     for (index = 0;; ++index) {
 	bufSize = MAX_KEY_LENGTH;
-	result = RegEnumKeyEx(key, index, buffer, &bufSize,
+	result = RegEnumKeyExW(key, index, buffer, &bufSize,
 		NULL, NULL, NULL, NULL);
 	if (result != ERROR_SUCCESS) {
 	    if (result == ERROR_NO_MORE_ITEMS) {
@@ -613,7 +633,8 @@ GetKeyNames(
 	    }
 	    break;
 	}
-	name = Tcl_WinTCharToUtf(buffer, bufSize * sizeof(TCHAR), &ds);
+	Tcl_DStringInit(&ds);
+	name = Tcl_WCharToUtfDString(buffer, bufSize, &ds);
 	if (pattern && !Tcl_StringMatch(name, pattern)) {
 	    Tcl_DStringFree(&ds);
 	    continue;
@@ -663,7 +684,7 @@ GetType(
     DWORD result, type;
     Tcl_DString ds;
     const char *valueName;
-    const TCHAR *nativeValue;
+    const WCHAR *nativeValue;
 
     /*
      * Attempt to open the key for reading.
@@ -679,8 +700,9 @@ GetType(
      */
 
     valueName = Tcl_GetString(valueNameObj);
-    nativeValue = Tcl_WinUtfToTChar(valueName, valueNameObj->length, &ds);
-    result = RegQueryValueEx(key, nativeValue, NULL, &type,
+    Tcl_DStringInit(&ds);
+    nativeValue = Tcl_UtfToWCharDString(valueName, valueNameObj->length, &ds);
+    result = RegQueryValueExW(key, nativeValue, NULL, &type,
 	    NULL, NULL);
     Tcl_DStringFree(&ds);
     RegCloseKey(key);
@@ -732,7 +754,7 @@ GetValue(
 {
     HKEY key;
     const char *valueName;
-    const TCHAR *nativeValue;
+    const WCHAR *nativeValue;
     DWORD result, length, type;
     Tcl_DString data, buf;
 
@@ -757,12 +779,13 @@ GetValue(
 
     Tcl_DStringInit(&data);
     Tcl_DStringSetLength(&data, TCL_DSTRING_STATIC_SIZE - 1);
-    length = TCL_DSTRING_STATIC_SIZE/sizeof(TCHAR) - 1;
+    length = TCL_DSTRING_STATIC_SIZE/sizeof(WCHAR) - 1;
 
     valueName = Tcl_GetString(valueNameObj);
-    nativeValue = Tcl_WinUtfToTChar(valueName, valueNameObj->length, &buf);
+    Tcl_DStringInit(&buf);
+    nativeValue = Tcl_UtfToWCharDString(valueName, valueNameObj->length, &buf);
 
-    result = RegQueryValueEx(key, nativeValue, NULL, &type,
+    result = RegQueryValueExW(key, nativeValue, NULL, &type,
 	    (BYTE *) Tcl_DStringValue(&data), &length);
     while (result == ERROR_MORE_DATA) {
 	/*
@@ -771,9 +794,9 @@ GetValue(
 	 * HKEY_PERFORMANCE_DATA
 	 */
 
-	length = Tcl_DStringLength(&data) * (2 / sizeof(TCHAR));
-	Tcl_DStringSetLength(&data, (int) length * sizeof(TCHAR));
-	result = RegQueryValueEx(key, nativeValue,
+	length = Tcl_DStringLength(&data) * (2 / sizeof(WCHAR));
+	Tcl_DStringSetLength(&data, (int) length * sizeof(WCHAR));
+	result = RegQueryValueExW(key, nativeValue,
 		NULL, &type, (BYTE *) Tcl_DStringValue(&data), &length);
     }
     Tcl_DStringFree(&buf);
@@ -809,13 +832,13 @@ GetValue(
 	 */
 
 	while ((p < end) && *((WCHAR *) p) != 0) {
-	    WCHAR *wp;
+	    WCHAR *wp = (WCHAR *) p;
 
-	    Tcl_WinTCharToUtf((TCHAR *) p, -1, &buf);
+	    Tcl_DStringInit(&buf);
+	    Tcl_WCharToUtfDString(wp, wcslen(wp), &buf);
 	    Tcl_ListObjAppendElement(interp, resultPtr,
 		    Tcl_NewStringObj(Tcl_DStringValue(&buf),
 			    Tcl_DStringLength(&buf)));
-	    wp = (WCHAR *) p;
 
 	    while (*wp++ != 0) {/* empty body */}
 	    p = (char *) wp;
@@ -823,7 +846,9 @@ GetValue(
 	}
 	Tcl_SetObjResult(interp, resultPtr);
     } else if ((type == REG_SZ) || (type == REG_EXPAND_SZ)) {
-	Tcl_WinTCharToUtf((TCHAR *) Tcl_DStringValue(&data), -1, &buf);
+	WCHAR *wp = (WCHAR *) Tcl_DStringValue(&data);
+	Tcl_DStringInit(&buf);
+	Tcl_WCharToUtfDString((const WCHAR *)Tcl_DStringValue(&data), wcslen(wp), &buf);
 	Tcl_DStringResult(interp, &buf);
     } else {
 	/*
@@ -880,7 +905,7 @@ GetValueNames(
 
     resultPtr = Tcl_NewObj();
     Tcl_DStringInit(&buffer);
-    Tcl_DStringSetLength(&buffer, (int) (MAX_KEY_LENGTH * sizeof(TCHAR)));
+    Tcl_DStringSetLength(&buffer, (int) (MAX_KEY_LENGTH * sizeof(WCHAR)));
     index = 0;
     result = TCL_OK;
 
@@ -897,12 +922,11 @@ GetValueNames(
      */
 
     size = MAX_KEY_LENGTH;
-    while (RegEnumValue(key,index, (TCHAR *)Tcl_DStringValue(&buffer),
+    while (RegEnumValueW(key,index, (WCHAR *)Tcl_DStringValue(&buffer),
 	    &size, NULL, NULL, NULL, NULL) == ERROR_SUCCESS) {
-	size *= sizeof(TCHAR);
 
-	Tcl_WinTCharToUtf((TCHAR *) Tcl_DStringValue(&buffer), (int) size,
-		&ds);
+	Tcl_DStringInit(&ds);
+	Tcl_WCharToUtfDString((const WCHAR *)Tcl_DStringValue(&buffer), size, &ds);
 	name = Tcl_DStringValue(&ds);
 	if (!pattern || Tcl_StringMatch(name, pattern)) {
 	    result = Tcl_ListObjAppendElement(interp, resultPtr,
@@ -1008,8 +1032,9 @@ OpenSubKey(
      */
 
     if (hostName) {
-	hostName = (char *) Tcl_WinUtfToTChar(hostName, -1, &buf);
-	result = RegConnectRegistry((TCHAR *)hostName, rootKey,
+	Tcl_DStringInit(&buf);
+	hostName = (char *) Tcl_UtfToWCharDString(hostName, -1, &buf);
+	result = RegConnectRegistryW((WCHAR *)hostName, rootKey,
 		&rootKey);
 	Tcl_DStringFree(&buf);
 	if (result != ERROR_SUCCESS) {
@@ -1023,12 +1048,13 @@ OpenSubKey(
      */
 
     if (keyName) {
-	keyName = (char *) Tcl_WinUtfToTChar(keyName, -1, &buf);
+	Tcl_DStringInit(&buf);
+	keyName = (char *) Tcl_UtfToWCharDString(keyName, -1, &buf);
     }
     if (flags & REG_CREATE) {
 	DWORD create;
 
-	result = RegCreateKeyEx(rootKey, (TCHAR *)keyName, 0, NULL,
+	result = RegCreateKeyExW(rootKey, (WCHAR *)keyName, 0, NULL,
 		REG_OPTION_NON_VOLATILE, mode, NULL, keyPtr, &create);
     } else if (rootKey == HKEY_PERFORMANCE_DATA) {
 	/*
@@ -1039,7 +1065,7 @@ OpenSubKey(
 	*keyPtr = HKEY_PERFORMANCE_DATA;
 	result = ERROR_SUCCESS;
     } else {
-	result = RegOpenKeyEx(rootKey, (TCHAR *)keyName, 0, mode,
+	result = RegOpenKeyExW(rootKey, (WCHAR *)keyName, 0, mode,
 		keyPtr);
     }
     if (keyName) {
@@ -1159,7 +1185,7 @@ ParseKeyName(
 static DWORD
 RecursiveDeleteKey(
     HKEY startKey,		/* Parent of key to be deleted. */
-    const TCHAR *keyName,	/* Name of key to be deleted in external
+    const WCHAR *keyName,	/* Name of key to be deleted in external
 				 * encoding, not UTF. */
     REGSAM mode)		/* Mode flags to pass. */
 {
@@ -1168,7 +1194,7 @@ RecursiveDeleteKey(
     HKEY hKey;
     REGSAM saveMode = mode;
     static int checkExProc = 0;
-    static FARPROC regDeleteKeyExProc = NULL;
+    static LSTATUS (* regDeleteKeyExProc) (HKEY, LPCWSTR, REGSAM, DWORD) = (LSTATUS (*) (HKEY, LPCWSTR, REGSAM, DWORD)) NULL;
 
     /*
      * Do not allow NULL or empty key name.
@@ -1179,13 +1205,13 @@ RecursiveDeleteKey(
     }
 
     mode |= KEY_ENUMERATE_SUB_KEYS | DELETE | KEY_QUERY_VALUE;
-    result = RegOpenKeyEx(startKey, keyName, 0, mode, &hKey);
+    result = RegOpenKeyExW(startKey, keyName, 0, mode, &hKey);
     if (result != ERROR_SUCCESS) {
 	return result;
     }
 
     Tcl_DStringInit(&subkey);
-    Tcl_DStringSetLength(&subkey, (int) (MAX_KEY_LENGTH * sizeof(TCHAR)));
+    Tcl_DStringSetLength(&subkey, (int) (MAX_KEY_LENGTH * sizeof(WCHAR)));
 
     mode = saveMode;
     while (result == ERROR_SUCCESS) {
@@ -1194,7 +1220,7 @@ RecursiveDeleteKey(
 	 */
 
 	size = MAX_KEY_LENGTH;
-	result = RegEnumKeyEx(hKey, 0, (TCHAR *)Tcl_DStringValue(&subkey),
+	result = RegEnumKeyExW(hKey, 0, (WCHAR *)Tcl_DStringValue(&subkey),
 		&size, NULL, NULL, NULL, NULL);
 	if (result == ERROR_NO_MORE_ITEMS) {
 	    /*
@@ -1207,19 +1233,19 @@ RecursiveDeleteKey(
 		HMODULE handle;
 
 		checkExProc = 1;
-		handle = GetModuleHandle(TEXT("ADVAPI32"));
-		regDeleteKeyExProc = (FARPROC)
+		handle = GetModuleHandleW(L"ADVAPI32");
+		regDeleteKeyExProc = (LSTATUS (*) (HKEY, LPCWSTR, REGSAM, DWORD))
 			GetProcAddress(handle, "RegDeleteKeyExW");
 	    }
 	    if (mode && regDeleteKeyExProc) {
 		result = regDeleteKeyExProc(startKey, keyName, mode, 0);
 	    } else {
-		result = RegDeleteKey(startKey, keyName);
+		result = RegDeleteKeyW(startKey, keyName);
 	    }
 	    break;
 	} else if (result == ERROR_SUCCESS) {
 	    result = RecursiveDeleteKey(hKey,
-		    (const TCHAR *) Tcl_DStringValue(&subkey), mode);
+		    (const WCHAR *) Tcl_DStringValue(&subkey), mode);
 	}
     }
     Tcl_DStringFree(&subkey);
@@ -1275,7 +1301,8 @@ SetValue(
     }
 
     valueName = Tcl_GetString(valueNameObj);
-    valueName = (char *) Tcl_WinUtfToTChar(valueName, valueNameObj->length, &nameBuf);
+    Tcl_DStringInit(&nameBuf);
+    valueName = (char *) Tcl_UtfToWCharDString(valueName, valueNameObj->length, &nameBuf);
 
     if (type == REG_DWORD || type == REG_DWORD_BIG_ENDIAN) {
 	int value;
@@ -1287,7 +1314,7 @@ SetValue(
 	}
 
 	value = ConvertDWORD((DWORD) type, (DWORD) value);
-	result = RegSetValueEx(key, (TCHAR *) valueName, 0,
+	result = RegSetValueExW(key, (WCHAR *) valueName, 0,
 		(DWORD) type, (BYTE *) &value, sizeof(DWORD));
     } else if (type == REG_MULTI_SZ) {
 	Tcl_DString data, buf;
@@ -1319,9 +1346,10 @@ SetValue(
 	    Tcl_DStringAppend(&data, "", 1);	/* NUL-terminated string */
 	}
 
-	Tcl_WinUtfToTChar(Tcl_DStringValue(&data), Tcl_DStringLength(&data)+1,
+	Tcl_DStringInit(&buf);
+	Tcl_UtfToWCharDString(Tcl_DStringValue(&data), Tcl_DStringLength(&data)+1,
 		&buf);
-	result = RegSetValueEx(key, (TCHAR *) valueName, 0,
+	result = RegSetValueExW(key, (WCHAR *) valueName, 0,
 		(DWORD) type, (BYTE *) Tcl_DStringValue(&buf),
 		(DWORD) Tcl_DStringLength(&buf));
 	Tcl_DStringFree(&data);
@@ -1330,7 +1358,8 @@ SetValue(
 	Tcl_DString buf;
 	const char *data = Tcl_GetString(dataObj);
 
-	data = (char *) Tcl_WinUtfToTChar(data, dataObj->length, &buf);
+	Tcl_DStringInit(&buf);
+	data = (char *) Tcl_UtfToWCharDString(data, dataObj->length, &buf);
 
 	/*
 	 * Include the null in the length, padding if needed for WCHAR.
@@ -1338,7 +1367,7 @@ SetValue(
 
 	Tcl_DStringSetLength(&buf, Tcl_DStringLength(&buf)+1);
 
-	result = RegSetValueEx(key, (TCHAR *) valueName, 0,
+	result = RegSetValueExW(key, (WCHAR *) valueName, 0,
 		(DWORD) type, (BYTE *) data, (DWORD) Tcl_DStringLength(&buf) + 1);
 	Tcl_DStringFree(&buf);
     } else {
@@ -1350,7 +1379,7 @@ SetValue(
 	 */
 
 	data = (BYTE *) getByteArrayFromObj(dataObj, &bytelength);
-	result = RegSetValueEx(key, (TCHAR *) valueName, 0,
+	result = RegSetValueExW(key, (WCHAR *) valueName, 0,
 		(DWORD) type, data, (DWORD) bytelength);
     }
 
@@ -1410,7 +1439,8 @@ BroadcastValue(
     }
 
     str = Tcl_GetString(objv[0]);
-    wstr = (WCHAR *) Tcl_WinUtfToTChar(str, objv[0]->length, &ds);
+    Tcl_DStringInit(&ds);
+    wstr = Tcl_UtfToWCharDString(str, objv[0]->length, &ds);
     if (Tcl_DStringLength(&ds) == 0) {
 	wstr = NULL;
     }
@@ -1419,7 +1449,7 @@ BroadcastValue(
      * Use the ignore the result.
      */
 
-    result = SendMessageTimeout(HWND_BROADCAST, WM_SETTINGCHANGE,
+    result = SendMessageTimeoutW(HWND_BROADCAST, WM_SETTINGCHANGE,
 	    (WPARAM) 0, (LPARAM) wstr, SMTO_ABORTIFHUNG, (UINT) timeout, &sendResult);
     Tcl_DStringFree(&ds);
 
@@ -1454,7 +1484,7 @@ AppendSystemError(
     DWORD error)		/* Result code from error. */
 {
     int length;
-    TCHAR *tMsgPtr, **tMsgPtrPtr = &tMsgPtr;
+    WCHAR *tMsgPtr, **tMsgPtrPtr = &tMsgPtr;
     const char *msg;
     char id[TCL_INTEGER_SPACE], msgBuf[24 + TCL_INTEGER_SPACE];
     Tcl_DString ds;
@@ -1463,9 +1493,9 @@ AppendSystemError(
     if (Tcl_IsShared(resultPtr)) {
 	resultPtr = Tcl_DuplicateObj(resultPtr);
     }
-    length = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM
+    length = FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM
 	    | FORMAT_MESSAGE_ALLOCATE_BUFFER, NULL, error,
-	    MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (TCHAR *) tMsgPtrPtr,
+	    MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (WCHAR *) tMsgPtrPtr,
 	    0, NULL);
     if (length == 0) {
 	sprintf(msgBuf, "unknown error: %ld", error);
@@ -1473,7 +1503,8 @@ AppendSystemError(
     } else {
 	char *msgPtr;
 
-	Tcl_WinTCharToUtf(tMsgPtr, -1, &ds);
+	Tcl_DStringInit(&ds);
+	Tcl_WCharToUtfDString(tMsgPtr, wcslen(tMsgPtr), &ds);
 	LocalFree(tMsgPtr);
 
 	msgPtr = Tcl_DStringValue(&ds);