Merge trunk

23 files changed, 468 insertions, 381 deletions

diff --git a/.travis.yml b/.travis.yml
index 113f11c..75d4a9c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,7 +17,6 @@ matrix:
       env:
         - CFGOPT="--disable-shared"
         - BUILD_DIR=unix
-# Debug build. Running test-cases disabled, because it is currently failing.
     - name: "Linux/GCC/Debug"
       os: linux
       dist: xenial
@@ -81,6 +80,20 @@ matrix:
       compiler: clang
       env:
         - BUILD_DIR=unix
+    - name: "Linux/Clang/Shared: UTF_MAX=6"
+      os: linux
+      dist: xenial
+      compiler: clang
+      env:
+        - BUILD_DIR=unix
+        - CFGOPT=CFLAGS=-DTCL_UTF_MAX=6
+    - name: "Linux/Clang/Shared: UTF_MAX=3"
+      os: linux
+      dist: xenial
+      compiler: clang
+      env:
+        - BUILD_DIR=unix
+        - CFGOPT=CFLAGS=-DTCL_UTF_MAX=3
     - name: "Linux/Clang/Static"
       os: linux
       dist: xenial
diff --git a/generic/tclExecute.c b/generic/tclExecute.c
index a4b5d38..562779c 100644
--- a/generic/tclExecute.c
+++ b/generic/tclExecute.c
@@ -2022,7 +2022,7 @@ TEBCresume(
      */
 
     Tcl_Obj *objPtr, *valuePtr, *value2Ptr, *part1Ptr, *part2Ptr, *tmpPtr;
-    Tcl_Obj **objv;
+    Tcl_Obj **objv = NULL;
     int objc = 0;
     int opnd, length, pcAdjustment;
     Var *varPtr, *arrayPtr;
diff --git a/generic/tclPlatDecls.h b/generic/tclPlatDecls.h
index b1a874f..18e464c 100644
--- a/generic/tclPlatDecls.h
+++ b/generic/tclPlatDecls.h
@@ -99,16 +99,11 @@ extern const TclPlatStubs *tclPlatStubsPtr;
 #undef TCL_STORAGE_CLASS
 #define TCL_STORAGE_CLASS DLLIMPORT
 
-#if defined(USE_TCL_STUBS) && (defined(_WIN32) || defined(__CYGWIN__))\
-	&& (defined(TCL_NO_DEPRECATED) || TCL_MAJOR_VERSION > 8)
-#undef Tcl_WinUtfToTChar
-#undef Tcl_WinTCharToUtf
-#ifdef _WIN32
+#if defined(USE_TCL_STUBS) && defined(_WIN32) && !defined(TCL_NO_DEPRECATED)
 #define Tcl_WinUtfToTChar(string, len, dsPtr) (Tcl_DStringInit(dsPtr), \
 		(TCHAR *)Tcl_UtfToChar16DString((string), (len), (dsPtr)))
 #define Tcl_WinTCharToUtf(string, len, dsPtr) (Tcl_DStringInit(dsPtr), \
-		(char *)Tcl_Char16ToUtfDString((string), ((((len) + 2) >> 1) - 1), (dsPtr)))
-#endif
+		(char *)Tcl_Char16ToUtfDString((const unsigned short *)(string), ((((len) + 2) >> 1) - 1), (dsPtr)))
 #endif
 
 #endif /* _TCLPLATDECLS */
diff --git a/tests/all.tcl b/tests/all.tcl
index 287de1f..52c8763 100644
--- a/tests/all.tcl
+++ b/tests/all.tcl
@@ -25,4 +25,9 @@ if {[singleProcess]} {
 set ErrorOnFailures [info exists env(ERROR_ON_FAILURES)]
 unset -nocomplain env(ERROR_ON_FAILURES)
 if {[runAllTests] && $ErrorOnFailures} {exit 1}
-proc exit args {}
+# if calling direct only (avoid rewrite exit if inlined or interactive):
+if { [info exists ::argv0] && [file tail $::argv0] eq [file tail [info script]]
+  && !([info exists ::tcl_interactive] && $::tcl_interactive)
+} {
+    proc exit args {}
+}
\ No newline at end of file
diff --git a/tests/basic.test b/tests/basic.test
index 4561667..428fd93 100644
--- a/tests/basic.test
+++ b/tests/basic.test
@@ -964,7 +964,7 @@ test basic-48.24.$noComp {expansion: empty not canonical list, regression test,
     run {list [list {*}{ }] [list {*}[format %c 32]] [list {*}[set a { }]]}
 } -result [lrepeat 3 {}] -cleanup {unset -nocomplain a}
 
-test basic-48.25.$noComp {Bug cc191552c: expansion: empty non-canonical list} -setup {
+test basic-48.25.$noComp {Bug cc191552c: expansion: empty non-canonical list} -constraints $constraints -setup {
     unset -nocomplain ::CRLF
     set ::CRLF "\r\n"
 } -body {
diff --git a/tests/lrange.test b/tests/lrange.test
index dcc0eec..4f7c0d3 100644
--- a/tests/lrange.test
+++ b/tests/lrange.test
@@ -133,15 +133,19 @@ test lrange-3.7b.2 {not compiled on empty not list object, 2nd regression test,
     list [$cmd {} 0 1] [$cmd [lindex a -1] 0 1] [$cmd [set a {}] 0 1] \
 	 [$cmd {} 0-1 end+1] [$cmd [lindex a -1] 0-1 end+1] [$cmd $a 0-1 end+1]
 } [lrepeat 6 {}]
-test lrange-3.7c.2 {compiled on empty pure bytes object, 2nd regression test, bug [cc1e91552c]} {
+test lrange-3.7c.2 {compiled on empty pure bytes object, 2nd regression test, bug [cc1e91552c]} -constraints {
+    testpurebytesobj
+} -body {
     list [lrange [testpurebytesobj] 0 1] [lrange [testpurebytesobj { }] 0 1] [lrange [set a [testpurebytesobj {}]] 0 1] \
 	 [lrange [testpurebytesobj] 0-1 end+1] [lrange [testpurebytesobj { }] 0-1 end+1] [lrange $a 0-1 end+1]
-} [lrepeat 6 {}]
-test lrange-3.7d.2 {not compiled on empty pure bytes object, 2nd regression test, bug [cc1e91552c]} {
+} -result [lrepeat 6 {}]
+test lrange-3.7d.2 {not compiled on empty pure bytes object, 2nd regression test, bug [cc1e91552c]} -constraints {
+    testpurebytesobj
+} -body {
     set cmd lrange
     list [$cmd [testpurebytesobj] 0 1] [$cmd [testpurebytesobj { }] 0 1] [$cmd [set a [testpurebytesobj {}]] 0 1] \
 	 [$cmd [testpurebytesobj] 0-1 end+1] [$cmd [testpurebytesobj { }] 0-1 end+1] [$cmd $a 0-1 end+1]
-} [lrepeat 6 {}]
+} -result [lrepeat 6 {}]
 
 test lrange-4.1 {lrange pure promise} -body {
     set ll1 [list $tcl_version 2 3 4]
diff --git a/unix/tclSelectNotfy.c b/unix/tclSelectNotfy.c
index f77379b..f9e99aa 100644
--- a/unix/tclSelectNotfy.c
+++ b/unix/tclSelectNotfy.c
@@ -231,7 +231,7 @@ typedef struct {
     void *hbrBackground;
     void *lpszMenuName;
     const void *lpszClassName;
-} WNDCLASS;
+} WNDCLASSW;
 
 extern void __stdcall	CloseHandle(void *);
 extern void *__stdcall	CreateEventW(void *, unsigned char, unsigned char,
@@ -249,7 +249,7 @@ extern unsigned char __stdcall	PeekMessageW(MSG *, void *, int, int, int);
 extern unsigned char __stdcall	PostMessageW(void *, unsigned int, void *,
 				    void *);
 extern void __stdcall	PostQuitMessage(int);
-extern void *__stdcall	RegisterClassW(const WNDCLASS *);
+extern void *__stdcall	RegisterClassW(const WNDCLASSW *);
 extern unsigned char __stdcall	ResetEvent(void *);
 extern unsigned char __stdcall	TranslateMessage(const MSG *);
 
@@ -297,7 +297,7 @@ Tcl_InitNotifier(void)
 	 */
 	if (tsdPtr->waitCVinitialized == 0) {
 #ifdef __CYGWIN__
-	    WNDCLASS class;
+	    WNDCLASSW class;
 
 	    class.style = 0;
 	    class.cbClsExtra = 0;
diff --git a/win/tclWin32Dll.c b/win/tclWin32Dll.c
index a286254..8299eed 100644
--- a/win/tclWin32Dll.c
+++ b/win/tclWin32Dll.c
@@ -314,7 +314,7 @@ TclWinDriveLetterForVolMountPoint(
 	     * Try to read the volume mount point and see where it points.
 	     */
 
-	    if (GetVolumeNameForVolumeMountPoint(drive,
+	    if (GetVolumeNameForVolumeMountPointW(drive,
 		    Target, 55) != 0) {
 		if (wcscmp(dlIter->volumeName, Target) == 0) {
 		    /*
@@ -373,7 +373,7 @@ TclWinDriveLetterForVolMountPoint(
 	 * Try to read the volume mount point and see where it points.
 	 */
 
-	if (GetVolumeNameForVolumeMountPoint(drive,
+	if (GetVolumeNameForVolumeMountPointW(drive,
 		Target, 55) != 0) {
 	    int alreadyStored = 0;
 
diff --git a/win/tclWinChan.c b/win/tclWinChan.c
index 1f9c757..6989344 100644
--- a/win/tclWinChan.c
+++ b/win/tclWinChan.c
@@ -946,7 +946,7 @@ TclpOpenFileChannel(
 	    flags = FILE_ATTRIBUTE_READONLY;
 	}
     } else {
-	flags = GetFileAttributes(nativeName);
+	flags = GetFileAttributesW(nativeName);
 	if (flags == 0xFFFFFFFF) {
 	    flags = 0;
 	}
@@ -962,7 +962,7 @@ TclpOpenFileChannel(
      * Now we get to create the file.
      */
 
-    handle = CreateFile(nativeName, accessMode, shareMode,
+    handle = CreateFileW(nativeName, accessMode, shareMode,
 	    NULL, createMode, flags, (HANDLE) NULL);
 
     if (handle == INVALID_HANDLE_VALUE) {
diff --git a/win/tclWinConsole.c b/win/tclWinConsole.c
index 177837a..eb13150 100644
--- a/win/tclWinConsole.c
+++ b/win/tclWinConsole.c
@@ -1055,7 +1055,7 @@ WaitForRead(
 	    return 1;
 	}
 
-	if (PeekConsoleInput(handle, &input, 1, &count) == FALSE) {
+	if (PeekConsoleInputW(handle, &input, 1, &count) == FALSE) {
 	    /*
 	     * Check to see if the peek failed because of EOF.
 	     */
@@ -1357,7 +1357,7 @@ TclWinOpenConsoleChannel(
 	modes |= ENABLE_LINE_INPUT;
 	SetConsoleMode(infoPtr->handle, modes);
 
-	infoPtr->reader.readyEvent = CreateEvent(NULL, TRUE, TRUE, NULL);
+	infoPtr->reader.readyEvent = CreateEventW(NULL, TRUE, TRUE, NULL);
 	infoPtr->reader.thread = CreateThread(NULL, 256, ConsoleReaderThread,
 		TclPipeThreadCreateTI(&infoPtr->reader.TI, infoPtr,
 			infoPtr->reader.readyEvent), 0, NULL);
@@ -1366,7 +1366,7 @@ TclWinOpenConsoleChannel(
 
     if (permissions & TCL_WRITABLE) {
 
-	infoPtr->writer.readyEvent = CreateEvent(NULL, TRUE, TRUE, NULL);
+	infoPtr->writer.readyEvent = CreateEventW(NULL, TRUE, TRUE, NULL);
 	infoPtr->writer.thread = CreateThread(NULL, 256, ConsoleWriterThread,
 		TclPipeThreadCreateTI(&infoPtr->writer.TI, infoPtr,
 			infoPtr->writer.readyEvent), 0, NULL);
diff --git a/win/tclWinDde.c b/win/tclWinDde.c
index 27ddfc8..0d76088 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;
 }
@@ -1081,7 +1107,7 @@ 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);
 #endif
@@ -1090,7 +1116,7 @@ DdeClientWindowProc(
     case WM_DDE_ACK:
 	return DdeServicesOnAck(hwnd, wParam, lParam);
     default:
-	return DefWindowProc(hwnd, uMsg, wParam, lParam);
+	return DefWindowProcW(hwnd, uMsg, wParam, lParam);
     }
 }
 
@@ -1104,11 +1130,11 @@ 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);
 #endif
@@ -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/tclWinFCmd.c b/win/tclWinFCmd.c
index f080d9f..b796b29 100644
--- a/win/tclWinFCmd.c
+++ b/win/tclWinFCmd.c
@@ -214,12 +214,12 @@ DoRenameFile(
 	"movl	    %%edx,	    %%fs:0"	    "\n\t"
 
 	/*
-	 * Call MoveFile(nativeSrc, nativeDst)
+	 * Call MoveFileW(nativeSrc, nativeDst)
 	 */
 
 	"pushl	    %%ebx"			    "\n\t"
 	"pushl	    %%ecx"			    "\n\t"
-	"movl	    %[moveFile],    %%eax"	    "\n\t"
+	"movl	    %[moveFileW],    %%eax"	    "\n\t"
 	"call	    *%%eax"			    "\n\t"
 
 	/*
@@ -256,7 +256,7 @@ DoRenameFile(
 	[registration]	"m"	(registration),
 	[nativeDst]	"m"	(nativeDst),
 	[nativeSrc]	"m"	(nativeSrc),
-	[moveFile]	"r"	(MoveFile)
+	[moveFileW]	"r"	(MoveFileW)
 	:
 	"%eax", "%ebx", "%ecx", "%edx", "memory"
 	);
@@ -267,7 +267,7 @@ DoRenameFile(
 #ifndef HAVE_NO_SEH
     __try {
 #endif
-	if ((*MoveFile)(nativeSrc, nativeDst) != FALSE) {
+	if ((*MoveFileW)(nativeSrc, nativeDst) != FALSE) {
 	    retval = TCL_OK;
 	}
 #ifndef HAVE_NO_SEH
@@ -281,10 +281,10 @@ DoRenameFile(
 
     TclWinConvertError(GetLastError());
 
-    srcAttr = GetFileAttributes(nativeSrc);
-    dstAttr = GetFileAttributes(nativeDst);
+    srcAttr = GetFileAttributesW(nativeSrc);
+    dstAttr = GetFileAttributesW(nativeDst);
     if (srcAttr == 0xffffffff) {
-	if (GetFullPathName(nativeSrc, 0, NULL,
+	if (GetFullPathNameW(nativeSrc, 0, NULL,
 		NULL) >= MAX_PATH) {
 	    errno = ENAMETOOLONG;
 	    return TCL_ERROR;
@@ -292,7 +292,7 @@ DoRenameFile(
 	srcAttr = 0;
     }
     if (dstAttr == 0xffffffff) {
-	if (GetFullPathName(nativeDst, 0, NULL,
+	if (GetFullPathNameW(nativeDst, 0, NULL,
 		NULL) >= MAX_PATH) {
 	    errno = ENAMETOOLONG;
 	    return TCL_ERROR;
@@ -315,18 +315,18 @@ DoRenameFile(
 	    Tcl_DString srcString, dstString;
 	    const char *src, *dst;
 
-	    size = GetFullPathName(nativeSrc, MAX_PATH,
+	    size = GetFullPathNameW(nativeSrc, MAX_PATH,
 		    nativeSrcPath, &nativeSrcRest);
 	    if ((size == 0) || (size > MAX_PATH)) {
 		return TCL_ERROR;
 	    }
-	    size = GetFullPathName(nativeDst, MAX_PATH,
+	    size = GetFullPathNameW(nativeDst, MAX_PATH,
 		    nativeDstPath, &nativeDstRest);
 	    if ((size == 0) || (size > MAX_PATH)) {
 		return TCL_ERROR;
 	    }
-	    CharLower(nativeSrcPath);
-	    CharLower(nativeDstPath);
+	    CharLowerW(nativeSrcPath);
+	    CharLowerW(nativeDstPath);
 
 	    Tcl_DStringInit(&srcString);
 	    Tcl_DStringInit(&dstString);
@@ -410,7 +410,7 @@ DoRenameFile(
 		     * directory back, for completeness.
 		     */
 
-		    if (MoveFile(nativeSrc,
+		    if (MoveFileW(nativeSrc,
 			    nativeDst) != FALSE) {
 			return TCL_OK;
 		    }
@@ -421,8 +421,8 @@ DoRenameFile(
 		     */
 
 		    TclWinConvertError(GetLastError());
-		    CreateDirectory(nativeDst, NULL);
-		    SetFileAttributes(nativeDst, dstAttr);
+		    CreateDirectoryW(nativeDst, NULL);
+		    SetFileAttributesW(nativeDst, dstAttr);
 		    if (Tcl_GetErrno() == EACCES) {
 			/*
 			 * Decode the EACCES to a more meaningful error.
@@ -451,7 +451,7 @@ DoRenameFile(
 		int result, size;
 		WCHAR tempBuf[MAX_PATH];
 
-		size = GetFullPathName(nativeDst, MAX_PATH,
+		size = GetFullPathNameW(nativeDst, MAX_PATH,
 			tempBuf, &nativeRest);
 		if ((size == 0) || (size > MAX_PATH) || (nativeRest == NULL)) {
 		    return TCL_ERROR;
@@ -460,8 +460,8 @@ DoRenameFile(
 		nativeRest[0] = '\0';
 
 		result = TCL_ERROR;
-		nativePrefix = (WCHAR *) L"tclr";
-		if (GetTempFileName(nativeTmp, nativePrefix,
+		nativePrefix = (WCHAR *)L"tclr";
+		if (GetTempFileNameW(nativeTmp, nativePrefix,
 			0, tempBuf) != 0) {
 		    /*
 		     * Strictly speaking, need the following DeleteFile and
@@ -471,15 +471,15 @@ DoRenameFile(
 		     */
 
 		    nativeTmp = tempBuf;
-		    DeleteFile(nativeTmp);
-		    if (MoveFile(nativeDst, nativeTmp) != FALSE) {
-			if (MoveFile(nativeSrc, nativeDst) != FALSE) {
-			    SetFileAttributes(nativeTmp, FILE_ATTRIBUTE_NORMAL);
-			    DeleteFile(nativeTmp);
+		    DeleteFileW(nativeTmp);
+		    if (MoveFileW(nativeDst, nativeTmp) != FALSE) {
+			if (MoveFileW(nativeSrc, nativeDst) != FALSE) {
+			    SetFileAttributesW(nativeTmp, FILE_ATTRIBUTE_NORMAL);
+			    DeleteFileW(nativeTmp);
 			    return TCL_OK;
 			} else {
-			    DeleteFile(nativeDst);
-			    MoveFile(nativeTmp, nativeDst);
+			    DeleteFileW(nativeDst);
+			    MoveFileW(nativeTmp, nativeDst);
 			}
 		    }
 
@@ -603,10 +603,10 @@ DoCopyFile(
 	"movl	    %%edx,	    %%fs:0"	    "\n\t"
 
 	/*
-	 * Call CopyFile(nativeSrc, nativeDst, 0)
+	 * Call CopyFileW(nativeSrc, nativeDst, 0)
 	 */
 
-	"movl	    %[copyFile],    %%eax"	    "\n\t"
+	"movl	    %[copyFileW],    %%eax"	    "\n\t"
 	"pushl	    $0"				    "\n\t"
 	"pushl	    %%ebx"			    "\n\t"
 	"pushl	    %%ecx"			    "\n\t"
@@ -646,7 +646,7 @@ DoCopyFile(
 	[registration]	"m"	(registration),
 	[nativeDst]	"m"	(nativeDst),
 	[nativeSrc]	"m"	(nativeSrc),
-	[copyFile]	"r"	(CopyFile)
+	[copyFileW]	"r"	(CopyFileW)
 	:
 	"%eax", "%ebx", "%ecx", "%edx", "memory"
 	);
@@ -657,7 +657,7 @@ DoCopyFile(
 #ifndef HAVE_NO_SEH
     __try {
 #endif
-	if (CopyFile(nativeSrc, nativeDst, 0) != FALSE) {
+	if (CopyFileW(nativeSrc, nativeDst, 0) != FALSE) {
 	    retval = TCL_OK;
 	}
 #ifndef HAVE_NO_SEH
@@ -677,8 +677,8 @@ DoCopyFile(
     if (Tcl_GetErrno() == EACCES) {
 	DWORD srcAttr, dstAttr;
 
-	srcAttr = GetFileAttributes(nativeSrc);
-	dstAttr = GetFileAttributes(nativeDst);
+	srcAttr = GetFileAttributesW(nativeSrc);
+	dstAttr = GetFileAttributesW(nativeDst);
 	if (srcAttr != 0xffffffff) {
 	    if (dstAttr == 0xffffffff) {
 		dstAttr = 0;
@@ -694,9 +694,9 @@ DoCopyFile(
 		Tcl_SetErrno(EISDIR);
 	    }
 	    if (dstAttr & FILE_ATTRIBUTE_READONLY) {
-		SetFileAttributes(nativeDst,
+		SetFileAttributesW(nativeDst,
 			dstAttr & ~((DWORD)FILE_ATTRIBUTE_READONLY));
-		if (CopyFile(nativeSrc, nativeDst,
+		if (CopyFileW(nativeSrc, nativeDst,
 			0) != FALSE) {
 		    return TCL_OK;
 		}
@@ -707,7 +707,7 @@ DoCopyFile(
 		 */
 
 		TclWinConvertError(GetLastError());
-		SetFileAttributes(nativeDst, dstAttr);
+		SetFileAttributesW(nativeDst, dstAttr);
 	    }
 	}
     }
@@ -763,13 +763,13 @@ TclpDeleteFile(
 	return TCL_ERROR;
     }
 
-    if (DeleteFile(path) != FALSE) {
+    if (DeleteFileW(path) != FALSE) {
 	return TCL_OK;
     }
     TclWinConvertError(GetLastError());
 
     if (Tcl_GetErrno() == EACCES) {
-	attr = GetFileAttributes(path);
+	attr = GetFileAttributesW(path);
 	if (attr != 0xffffffff) {
 	    if (attr & FILE_ATTRIBUTE_DIRECTORY) {
 		if (attr & FILE_ATTRIBUTE_REPARSE_POINT) {
@@ -790,21 +790,21 @@ TclpDeleteFile(
 
 		Tcl_SetErrno(EISDIR);
 	    } else if (attr & FILE_ATTRIBUTE_READONLY) {
-		int res = SetFileAttributes(path,
+		int res = SetFileAttributesW(path,
 			attr & ~((DWORD) FILE_ATTRIBUTE_READONLY));
 
 		if ((res != 0) &&
-			(DeleteFile(path) != FALSE)) {
+			(DeleteFileW(path) != FALSE)) {
 		    return TCL_OK;
 		}
 		TclWinConvertError(GetLastError());
 		if (res != 0) {
-		    SetFileAttributes(path, attr);
+		    SetFileAttributesW(path, attr);
 		}
 	    }
 	}
     } else if (Tcl_GetErrno() == ENOENT) {
-	attr = GetFileAttributes(path);
+	attr = GetFileAttributesW(path);
 	if (attr != 0xffffffff) {
 	    if (attr & FILE_ATTRIBUTE_DIRECTORY) {
 		/*
@@ -863,7 +863,7 @@ static int
 DoCreateDirectory(
     const WCHAR *nativePath)	/* Pathname of directory to create (native). */
 {
-    if (CreateDirectory(nativePath, NULL) == 0) {
+    if (CreateDirectoryW(nativePath, NULL) == 0) {
 	DWORD error = GetLastError();
 
 	TclWinConvertError(error);
@@ -1035,7 +1035,7 @@ DoRemoveJustDirectory(
 	return TCL_ERROR;
     }
 
-    attr = GetFileAttributes(nativePath);
+    attr = GetFileAttributesW(nativePath);
 
     if (attr & FILE_ATTRIBUTE_REPARSE_POINT) {
 	/*
@@ -1049,7 +1049,7 @@ DoRemoveJustDirectory(
 	 * Ordinary directory.
 	 */
 
-	if (RemoveDirectory(nativePath) != FALSE) {
+	if (RemoveDirectoryW(nativePath) != FALSE) {
 	    return TCL_OK;
 	}
     }
@@ -1057,7 +1057,7 @@ DoRemoveJustDirectory(
     TclWinConvertError(GetLastError());
 
     if (Tcl_GetErrno() == EACCES) {
-	attr = GetFileAttributes(nativePath);
+	attr = GetFileAttributesW(nativePath);
 	if (attr != 0xffffffff) {
 	    if ((attr & FILE_ATTRIBUTE_DIRECTORY) == 0) {
 		/*
@@ -1081,15 +1081,15 @@ DoRemoveJustDirectory(
 
 	    if (attr & FILE_ATTRIBUTE_READONLY) {
 		attr &= ~FILE_ATTRIBUTE_READONLY;
-		if (SetFileAttributes(nativePath,
+		if (SetFileAttributesW(nativePath,
 			attr) == FALSE) {
 		    goto end;
 		}
-		if (RemoveDirectory(nativePath) != FALSE) {
+		if (RemoveDirectoryW(nativePath) != FALSE) {
 		    return TCL_OK;
 		}
 		TclWinConvertError(GetLastError());
-		SetFileAttributes(nativePath,
+		SetFileAttributesW(nativePath,
 			attr | FILE_ATTRIBUTE_READONLY);
 	    }
 	}
@@ -1191,7 +1191,7 @@ TraverseWinTree(
     WCHAR *nativeSource, *nativeTarget, *nativeErrfile;
     int result, found, sourceLen, targetLen = 0, oldSourceLen, oldTargetLen;
     HANDLE handle;
-    WIN32_FIND_DATA data;
+    WIN32_FIND_DATAW data;
 
     nativeErrfile = NULL;
     result = TCL_OK;
@@ -1202,7 +1202,7 @@ TraverseWinTree(
 	    (targetPtr == NULL ? NULL : Tcl_DStringValue(targetPtr));
 
     oldSourceLen = Tcl_DStringLength(sourcePtr);
-    sourceAttr = GetFileAttributes(nativeSource);
+    sourceAttr = GetFileAttributesW(nativeSource);
     if (sourceAttr == 0xffffffff) {
 	nativeErrfile = nativeSource;
 	goto end;
@@ -1229,7 +1229,7 @@ TraverseWinTree(
     Tcl_DStringSetLength(sourcePtr, Tcl_DStringLength(sourcePtr) - 1);
 
     nativeSource = (WCHAR *) Tcl_DStringValue(sourcePtr);
-    handle = FindFirstFile(nativeSource, &data);
+    handle = FindFirstFileW(nativeSource, &data);
     if (handle == INVALID_HANDLE_VALUE) {
 	/*
 	 * Can't read directory.
@@ -1262,7 +1262,7 @@ TraverseWinTree(
     }
 
     found = 1;
-    for (; found; found = FindNextFile(handle, &data)) {
+    for (; found; found = FindNextFileW(handle, &data)) {
 	WCHAR *nativeName;
 	int len;
 
@@ -1378,9 +1378,9 @@ TraversalCopy(
 	break;
     case DOTREE_PRED:
 	if (DoCreateDirectory(nativeDst) == TCL_OK) {
-	    DWORD attr = GetFileAttributes(nativeSrc);
+	    DWORD attr = GetFileAttributesW(nativeSrc);
 
-	    if (SetFileAttributes(nativeDst,
+	    if (SetFileAttributesW(nativeDst,
 		    attr) != FALSE) {
 		return TCL_OK;
 	    }
@@ -1518,7 +1518,7 @@ GetWinFileAttributes(
     int attr;
 
     nativeName = Tcl_FSGetNativePath(fileName);
-    result = GetFileAttributes(nativeName);
+    result = GetFileAttributesW(nativeName);
 
     if (result == 0xffffffff) {
 	StatError(interp, fileName);
@@ -1649,7 +1649,7 @@ ConvertFileNameFormat(
 	    Tcl_DString dsTemp;
 	    const WCHAR *nativeName;
 	    const char *tempString;
-	    WIN32_FIND_DATA data;
+	    WIN32_FIND_DATAW data;
 	    HANDLE handle;
 	    DWORD attr;
 
@@ -1665,16 +1665,16 @@ ConvertFileNameFormat(
 	    Tcl_DStringInit(&ds);
 	    nativeName = Tcl_UtfToWCharDString(tempString, length, &ds);
 	    Tcl_DecrRefCount(tempPath);
-	    handle = FindFirstFile(nativeName, &data);
+	    handle = FindFirstFileW(nativeName, &data);
 	    if (handle == INVALID_HANDLE_VALUE) {
 		/*
-		 * FindFirstFile() doesn't like root directories. We would
+		 * FindFirstFileW() doesn't like root directories. We would
 		 * only get a root directory here if the caller specified "c:"
 		 * or "c:." and the current directory on the drive was the
 		 * root directory
 		 */
 
-		attr = GetFileAttributes(nativeName);
+		attr = GetFileAttributesW(nativeName);
 		if ((attr!=0xFFFFFFFF) && (attr & FILE_ATTRIBUTE_DIRECTORY)) {
 		    Tcl_DStringFree(&ds);
 		    goto simple;
@@ -1844,7 +1844,7 @@ SetWinFileAttributes(
     const WCHAR *nativeName;
 
     nativeName = Tcl_FSGetNativePath(fileName);
-    fileAttributes = old = GetFileAttributes(nativeName);
+    fileAttributes = old = GetFileAttributesW(nativeName);
 
     if (fileAttributes == 0xffffffff) {
 	StatError(interp, fileName);
@@ -1863,7 +1863,7 @@ SetWinFileAttributes(
     }
 
     if ((fileAttributes != old)
-	    && !SetFileAttributes(nativeName, fileAttributes)) {
+	    && !SetFileAttributesW(nativeName, fileAttributes)) {
 	StatError(interp, fileName);
 	return TCL_ERROR;
     }
@@ -1936,10 +1936,10 @@ TclpObjListVolumes(void)
 
     if (GetLogicalDriveStringsA(sizeof(buf), buf) == 0) {
 	/*
-	 * GetVolumeInformation() will detects all drives, but causes
+	 * GetVolumeInformationW() will detects all drives, but causes
 	 * chattering on empty floppy drives. We only do this if
 	 * GetLogicalDriveStrings() didn't work. It has also been reported
-	 * that on some laptops it takes a while for GetVolumeInformation() to
+	 * that on some laptops it takes a while for GetVolumeInformationW() to
 	 * return when pinging an empty floppy drive, another reason to try to
 	 * avoid calling it.
 	 */
diff --git a/win/tclWinFile.c b/win/tclWinFile.c
index 4073f9a..2c7cfd4 100644
--- a/win/tclWinFile.c
+++ b/win/tclWinFile.c
@@ -203,7 +203,7 @@ WinLink(
      * Get the full path referenced by the target.
      */
 
-    if (!GetFullPathName(linkTargetPath, MAX_PATH, tempFileName,
+    if (!GetFullPathNameW(linkTargetPath, MAX_PATH, tempFileName,
 	    &tempFilePart)) {
 	/*
 	 * Invalid file.
@@ -217,7 +217,7 @@ WinLink(
      * Make sure source file doesn't exist.
      */
 
-    attr = GetFileAttributes(linkSourcePath);
+    attr = GetFileAttributesW(linkSourcePath);
     if (attr != INVALID_FILE_ATTRIBUTES) {
 	Tcl_SetErrno(EEXIST);
 	return -1;
@@ -227,7 +227,7 @@ WinLink(
      * Get the full path referenced by the source file/directory.
      */
 
-    if (!GetFullPathName(linkSourcePath, MAX_PATH, tempFileName,
+    if (!GetFullPathNameW(linkSourcePath, MAX_PATH, tempFileName,
 	    &tempFilePart)) {
 	/*
 	 * Invalid file.
@@ -241,7 +241,7 @@ WinLink(
      * Check the target.
      */
 
-    attr = GetFileAttributes(linkTargetPath);
+    attr = GetFileAttributesW(linkTargetPath);
     if (attr == INVALID_FILE_ATTRIBUTES) {
 	/*
 	 * The target doesn't exist.
@@ -254,7 +254,7 @@ WinLink(
 	 */
 
 	if (linkAction & TCL_CREATE_HARD_LINK) {
-	    if (CreateHardLink(linkSourcePath, linkTargetPath, NULL)) {
+	    if (CreateHardLinkW(linkSourcePath, linkTargetPath, NULL)) {
 		/*
 		 * Success!
 		 */
@@ -316,7 +316,7 @@ WinReadLink(
      * Get the full path referenced by the target.
      */
 
-    if (!GetFullPathName(linkSourcePath, MAX_PATH, tempFileName,
+    if (!GetFullPathNameW(linkSourcePath, MAX_PATH, tempFileName,
 	    &tempFilePart)) {
 	/*
 	 * Invalid file.
@@ -330,7 +330,7 @@ WinReadLink(
      * Make sure source file does exist.
      */
 
-    attr = GetFileAttributes(linkSourcePath);
+    attr = GetFileAttributesW(linkSourcePath);
     if (attr == INVALID_FILE_ATTRIBUTES) {
 	/*
 	 * The source doesn't exist.
@@ -487,7 +487,7 @@ TclWinSymLinkDelete(
 
     memset(reparseBuffer, 0, sizeof(DUMMY_REPARSE_BUFFER));
     reparseBuffer->ReparseTag = IO_REPARSE_TAG_MOUNT_POINT;
-    hFile = CreateFile(linkOrigPath, GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
+    hFile = CreateFileW(linkOrigPath, GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
 	    FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_BACKUP_SEMANTICS, NULL);
 
     if (hFile != INVALID_HANDLE_VALUE) {
@@ -502,7 +502,7 @@ TclWinSymLinkDelete(
 	} else {
 	    CloseHandle(hFile);
 	    if (!linkOnly) {
-		RemoveDirectory(linkOrigPath);
+		RemoveDirectoryW(linkOrigPath);
 	    }
 	    return 0;
 	}
@@ -547,7 +547,7 @@ WinReadLinkDirectory(
     Tcl_DString ds;
     const char *copy;
 
-    attr = GetFileAttributes(linkDirPath);
+    attr = GetFileAttributesW(linkDirPath);
     if (!(attr & FILE_ATTRIBUTE_REPARSE_POINT)) {
 	goto invalidError;
     }
@@ -681,7 +681,7 @@ NativeReadReparse(
     HANDLE hFile;
     DWORD returnedLength;
 
-    hFile = CreateFile(linkDirPath, desiredAccess, FILE_SHARE_READ, NULL,
+    hFile = CreateFileW(linkDirPath, desiredAccess, FILE_SHARE_READ, NULL,
 	    OPEN_EXISTING,
 	    FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_BACKUP_SEMANTICS, NULL);
 
@@ -741,7 +741,7 @@ NativeWriteReparse(
      * Create the directory - it must not already exist.
      */
 
-    if (CreateDirectory(linkDirPath, NULL) == 0) {
+    if (CreateDirectoryW(linkDirPath, NULL) == 0) {
 	/*
 	 * Error creating directory.
 	 */
@@ -749,7 +749,7 @@ NativeWriteReparse(
 	TclWinConvertError(GetLastError());
 	return -1;
     }
-    hFile = CreateFile(linkDirPath, GENERIC_WRITE, 0, NULL,
+    hFile = CreateFileW(linkDirPath, GENERIC_WRITE, 0, NULL,
 	    OPEN_EXISTING, FILE_FLAG_OPEN_REPARSE_POINT
 	    | FILE_FLAG_BACKUP_SEMANTICS, NULL);
     if (hFile == INVALID_HANDLE_VALUE) {
@@ -774,7 +774,7 @@ NativeWriteReparse(
 
 	TclWinConvertError(GetLastError());
 	CloseHandle(hFile);
-	RemoveDirectory(linkDirPath);
+	RemoveDirectoryW(linkDirPath);
 	return -1;
     }
     CloseHandle(hFile);
@@ -920,7 +920,7 @@ TclpMatchInDirectory(
 
 	    native = Tcl_FSGetNativePath(pathPtr);
 
-	    if (GetFileAttributesEx(native,
+	    if (GetFileAttributesExW(native,
 		    GetFileExInfoStandard, &data) != TRUE) {
 		return TCL_OK;
 	    }
@@ -934,7 +934,7 @@ TclpMatchInDirectory(
     } else {
 	DWORD attr;
 	HANDLE handle;
-	WIN32_FIND_DATA data;
+	WIN32_FIND_DATAW data;
 	const char *dirName;	/* UTF-8 dir name, later with pattern
 				 * appended. */
 	size_t dirLength;
@@ -963,7 +963,7 @@ TclpMatchInDirectory(
 	if (native == NULL) {
 	    return TCL_OK;
 	}
-	attr = GetFileAttributes(native);
+	attr = GetFileAttributesW(native);
 
 	if ((attr == INVALID_FILE_ATTRIBUTES)
 	    || ((attr & FILE_ATTRIBUTE_DIRECTORY) == 0)) {
@@ -1007,13 +1007,13 @@ TclpMatchInDirectory(
 	Tcl_DStringInit(&ds);
 	native = Tcl_UtfToWCharDString(dirName, -1, &ds);
 	if ((types == NULL) || (types->type != TCL_GLOB_TYPE_DIR)) {
-	    handle = FindFirstFile(native, &data);
+	    handle = FindFirstFileW(native, &data);
 	} else {
 	    /*
 	     * We can be more efficient, for pure directory requests.
 	     */
 
-	    handle = FindFirstFileEx(native,
+	    handle = FindFirstFileExW(native,
 		    FindExInfoStandard, &data,
 		    FindExSearchLimitToDirectories, NULL, 0);
 	}
@@ -1139,7 +1139,7 @@ TclpMatchInDirectory(
 	     */
 
 	    Tcl_DStringFree(&ds);
-	} while (FindNextFile(handle, &data) == TRUE);
+	} while (FindNextFileW(handle, &data) == TRUE);
 
 	FindClose(handle);
 	Tcl_DStringFree(&dsOrig);
@@ -1573,7 +1573,7 @@ NativeAccess(
 {
     DWORD attr;
 
-    attr = GetFileAttributes(nativePath);
+    attr = GetFileAttributesW(nativePath);
 
     if (attr == INVALID_FILE_ATTRIBUTES) {
 	/*
@@ -1642,7 +1642,7 @@ NativeAccess(
 		mask |= GENERIC_EXECUTE;
 	    }
 
-	    hFile = CreateFile(nativePath, mask,
+	    hFile = CreateFileW(nativePath, mask,
 		    FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
 		    NULL, OPEN_EXISTING, FILE_FLAG_NO_BUFFERING, NULL);
 	    if (hFile != INVALID_HANDLE_VALUE) {
@@ -1692,7 +1692,7 @@ NativeAccess(
 	 */
 
 	size = 0;
-	GetFileSecurity(nativePath,
+	GetFileSecurityW(nativePath,
 		OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION
 		| DACL_SECURITY_INFORMATION | LABEL_SECURITY_INFORMATION,
 		0, 0, &size);
@@ -1723,10 +1723,10 @@ NativeAccess(
 	}
 
 	/*
-	 * Call GetFileSecurity() for real.
+	 * Call GetFileSecurityW() for real.
 	 */
 
-	if (!GetFileSecurity(nativePath,
+	if (!GetFileSecurityW(nativePath,
 		OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION
 		| DACL_SECURITY_INFORMATION | LABEL_SECURITY_INFORMATION,
 		sdPtr, size, &size)) {
@@ -1905,7 +1905,7 @@ TclpObjChdir(
     if (!nativePath) {
 	return -1;
     }
-    result = SetCurrentDirectory(nativePath);
+    result = SetCurrentDirectoryW(nativePath);
 
     if (result == 0) {
 	TclWinConvertError(GetLastError());
@@ -1946,7 +1946,7 @@ TclpGetCwd(
     char *p;
     WCHAR *native;
 
-    if (GetCurrentDirectory(MAX_PATH, buffer) == 0) {
+    if (GetCurrentDirectoryW(MAX_PATH, buffer) == 0) {
 	TclWinConvertError(GetLastError());
 	if (interp != NULL) {
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
@@ -2047,7 +2047,7 @@ NativeStat(
      * and if successful, mock up a BY_HANDLE_FILE_INFORMATION structure.
      */
 
-    fileHandle = CreateFile(nativePath, GENERIC_READ,
+    fileHandle = CreateFileW(nativePath, GENERIC_READ,
 	    FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
 	    NULL, OPEN_EXISTING,
 	    FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OPEN_REPARSE_POINT, NULL);
@@ -2105,17 +2105,17 @@ NativeStat(
 
 	WIN32_FILE_ATTRIBUTE_DATA data;
 
-	if (GetFileAttributesEx(nativePath,
+	if (GetFileAttributesExW(nativePath,
 		GetFileExInfoStandard, &data) != TRUE) {
 	    HANDLE hFind;
-	    WIN32_FIND_DATA ffd;
+	    WIN32_FIND_DATAW ffd;
 	    DWORD lasterror = GetLastError();
 
 	    if (lasterror != ERROR_SHARING_VIOLATION) {
 		TclWinConvertError(lasterror);
 		return -1;
 		}
-	    hFind = FindFirstFile(nativePath, &ffd);
+	    hFind = FindFirstFileW(nativePath, &ffd);
 	    if (hFind == INVALID_HANDLE_VALUE) {
 		TclWinConvertError(GetLastError());
 		return -1;
@@ -2173,7 +2173,7 @@ NativeDev(
     WCHAR *nativePart;
     const char *fullPath;
 
-    GetFullPathName(nativePath, MAX_PATH, nativeFullPath, &nativePart);
+    GetFullPathNameW(nativePath, MAX_PATH, nativeFullPath, &nativePart);
     Tcl_DStringInit(&ds);
     fullPath = Tcl_WCharToUtfDString(nativeFullPath, -1, &ds);
 
@@ -2199,11 +2199,11 @@ NativeDev(
 	Tcl_DStringInit(&volString);
 	nativeVol = Tcl_UtfToWCharDString(fullPath, p - fullPath, &volString);
 	dw = (DWORD) -1;
-	GetVolumeInformation(nativeVol, NULL, 0, &dw, NULL, NULL, NULL, 0);
+	GetVolumeInformationW(nativeVol, NULL, 0, &dw, NULL, NULL, NULL, 0);
 
 	/*
-	 * GetFullPathName() turns special devices like "NUL" into "\\.\NUL",
-	 * but GetVolumeInformation() returns failure for "\\.\NUL". This will
+	 * GetFullPathNameW() turns special devices like "NUL" into "\\.\NUL",
+	 * but GetVolumeInformationW() returns failure for "\\.\NUL". This will
 	 * cause "NUL" to get a drive number of -1, which makes about as much
 	 * sense as anything since the special devices don't live on any
 	 * drive.
@@ -2345,7 +2345,7 @@ TclpGetNativeCwd(
 {
     WCHAR buffer[MAX_PATH];
 
-    if (GetCurrentDirectory(MAX_PATH, buffer) == 0) {
+    if (GetCurrentDirectoryW(MAX_PATH, buffer) == 0) {
 	TclWinConvertError(GetLastError());
 	return NULL;
     }
@@ -2461,13 +2461,13 @@ TclpFilesystemPathType(
 
     firstSeparator = strchr(path, '/');
     if (firstSeparator == NULL) {
-	found = GetVolumeInformation(Tcl_FSGetNativePath(pathPtr),
+	found = GetVolumeInformationW(Tcl_FSGetNativePath(pathPtr),
 		NULL, 0, NULL, NULL, NULL, volType, VOL_BUF_SIZE);
     } else {
 	Tcl_Obj *driveName = Tcl_NewStringObj(path, firstSeparator - path+1);
 
 	Tcl_IncrRefCount(driveName);
-	found = GetVolumeInformation(Tcl_FSGetNativePath(driveName),
+	found = GetVolumeInformationW(Tcl_FSGetNativePath(driveName),
 		NULL, 0, NULL, NULL, NULL, volType, VOL_BUF_SIZE);
 	Tcl_DecrRefCount(driveName);
     }
@@ -2554,7 +2554,7 @@ TclpObjNormalizePath(
 	    nativePath = Tcl_UtfToWCharDString(path,
 		    currentPathEndPosition - path, &ds);
 
-	    if (GetFileAttributesEx(nativePath,
+	    if (GetFileAttributesExW(nativePath,
 		    GetFileExInfoStandard, &data) != TRUE) {
 		/*
 		 * File doesn't exist.
@@ -3229,7 +3229,7 @@ TclpUtime(
 
     native = Tcl_FSGetNativePath(pathPtr);
 
-    attr = GetFileAttributes(native);
+    attr = GetFileAttributesW(native);
 
     if (attr != INVALID_FILE_ATTRIBUTES && attr & FILE_ATTRIBUTE_DIRECTORY) {
 	flags = FILE_FLAG_BACKUP_SEMANTICS;
@@ -3240,7 +3240,7 @@ TclpUtime(
      * savings complications that utime gets wrong.
      */
 
-    fileHandle = CreateFile(native, FILE_WRITE_ATTRIBUTES, 0, NULL,
+    fileHandle = CreateFileW(native, FILE_WRITE_ATTRIBUTES, 0, NULL,
 	    OPEN_EXISTING, flags, NULL);
 
     if (fileHandle == INVALID_HANDLE_VALUE ||
@@ -3280,7 +3280,7 @@ TclWinFileOwned(
 
     native = Tcl_FSGetNativePath(pathPtr);
 
-    if (GetNamedSecurityInfo((LPTSTR) native, SE_FILE_OBJECT,
+    if (GetNamedSecurityInfoW((LPWSTR) native, SE_FILE_OBJECT,
 	    OWNER_SECURITY_INFORMATION, &ownerSid, NULL, NULL, NULL,
 	    &secd) != ERROR_SUCCESS) {
         /*
diff --git a/win/tclWinInit.c b/win/tclWinInit.c
index c6d5c1d..1f03b1d 100644
--- a/win/tclWinInit.c
+++ b/win/tclWinInit.c
@@ -17,7 +17,7 @@
 #include <lmcons.h>
 
 /*
- * GetUserName() is found in advapi32.dll
+ * GetUserNameW() is found in advapi32.dll
  */
 #ifdef _MSC_VER
 #   pragma comment(lib, "advapi32.lib")
@@ -149,13 +149,13 @@ TclpInitPlatform(void)
      * invoked.
      */
 
-    TclWinInit(GetModuleHandle(NULL));
+    TclWinInit(GetModuleHandleW(NULL));
 #endif
 
     /*
      * Fill available functions depending on windows version
      */
-    handle = GetModuleHandle(L"KERNEL32");
+    handle = GetModuleHandleW(L"KERNEL32");
     tclWinProcs.cancelSynchronousIo =
 	    (BOOL (WINAPI *)(HANDLE)) GetProcAddress(handle,
 	    "CancelSynchronousIo");
@@ -297,7 +297,7 @@ AppendEnvironment(
 	Tcl_SplitPath(buf, &pathc, &pathv);
 
 	/*
-	 * The lstrcmpi() will work even if pathv[pathc-1] is random UTF-8
+	 * The lstrcmpiA() will work even if pathv[pathc-1] is random UTF-8
 	 * chars because I know shortlib is ascii.
 	 */
 
@@ -472,7 +472,7 @@ TclpGetUserName(
 	WCHAR szUserName[UNLEN+1];
 	DWORD cchUserNameLen = UNLEN;
 
-	if (!GetUserName(szUserName, &cchUserNameLen)) {
+	if (!GetUserNameW(szUserName, &cchUserNameLen)) {
 	    return NULL;
 	}
 	cchUserNameLen--;
@@ -517,7 +517,7 @@ TclpSetVariables(
 	    TclGetProcessGlobalValue(&defaultLibraryDir), TCL_GLOBAL_ONLY);
 
     if (!osInfoInitialized) {
-	HMODULE handle = GetModuleHandle(L"NTDLL");
+	HMODULE handle = GetModuleHandleW(L"NTDLL");
 	int(__stdcall *getversion)(void *) =
 		(int(__stdcall *)(void *)) GetProcAddress(handle, "RtlGetVersion");
 	osInfo.dwOSVersionInfoSize = sizeof(OSVERSIONINFOW);
diff --git a/win/tclWinLoad.c b/win/tclWinLoad.c
index 254f59a..aac48af 100644
--- a/win/tclWinLoad.c
+++ b/win/tclWinLoad.c
@@ -76,7 +76,7 @@ TclpDlopen(
 
     nativeName = Tcl_FSGetNativePath(pathPtr);
     if (nativeName != NULL) {
-	hInstance = LoadLibraryEx(nativeName, NULL,
+	hInstance = LoadLibraryExW(nativeName, NULL,
 		LOAD_WITH_ALTERED_SEARCH_PATH);
     }
     if (hInstance == NULL) {
@@ -97,7 +97,7 @@ TclpDlopen(
 
 	Tcl_DStringInit(&ds);
 	nativeName = Tcl_UtfToWCharDString(TclGetString(pathPtr), -1, &ds);
-	hInstance = LoadLibraryEx(nativeName, NULL,
+	hInstance = LoadLibraryExW(nativeName, NULL,
 		LOAD_WITH_ALTERED_SEARCH_PATH);
 	Tcl_DStringFree(&ds);
     }
diff --git a/win/tclWinNotify.c b/win/tclWinNotify.c
index dba7a31..2ab4efa 100644
--- a/win/tclWinNotify.c
+++ b/win/tclWinNotify.c
@@ -98,7 +98,7 @@ Tcl_InitNotifier(void)
 
 	EnterCriticalSection(&notifierMutex);
 	if (notifierCount == 0) {
-	    WNDCLASS clazz;
+	    WNDCLASSW clazz;
 
 	    clazz.style = 0;
 	    clazz.cbClsExtra = 0;
@@ -111,7 +111,7 @@ Tcl_InitNotifier(void)
 	    clazz.hIcon = NULL;
 	    clazz.hCursor = NULL;
 
-	    if (!RegisterClass(&clazz)) {
+	    if (!RegisterClassW(&clazz)) {
 		Tcl_Panic("Unable to register TclNotifier window class");
 	    }
 	}
@@ -125,7 +125,7 @@ Tcl_InitNotifier(void)
 
 	tsdPtr->hwnd = NULL;
 	tsdPtr->thread = GetCurrentThreadId();
-	tsdPtr->event = CreateEvent(NULL, TRUE /* manual */,
+	tsdPtr->event = CreateEventW(NULL, TRUE /* manual */,
 		FALSE /* !signaled */, NULL);
 
 	return tsdPtr;
@@ -195,7 +195,7 @@ Tcl_FinalizeNotifier(
 	if (notifierCount) {
 	    notifierCount--;
 	    if (notifierCount == 0) {
-		UnregisterClass(className, TclWinGetTclInstance());
+		UnregisterClassW(className, TclWinGetTclInstance());
 	    }
 	}
 	LeaveCriticalSection(&notifierMutex);
@@ -247,7 +247,7 @@ Tcl_AlertNotifier(
 
 	    EnterCriticalSection(&tsdPtr->crit);
 	    if (!tsdPtr->pending) {
-		PostMessage(tsdPtr->hwnd, WM_WAKEUP, 0, 0);
+		PostMessageW(tsdPtr->hwnd, WM_WAKEUP, 0, 0);
 	    }
 	    tsdPtr->pending = 1;
 	    LeaveCriticalSection(&tsdPtr->crit);
@@ -359,7 +359,7 @@ Tcl_ServiceModeHook(
 	 */
 
 	if (mode == TCL_SERVICE_ALL && !tsdPtr->hwnd) {
-	    tsdPtr->hwnd = CreateWindow(className, className,
+	    tsdPtr->hwnd = CreateWindowW(className, className,
 		    WS_TILED, 0, 0, 0, 0, NULL, NULL, TclWinGetTclInstance(),
 		    NULL);
 
@@ -407,7 +407,7 @@ NotifierProc(
 	tsdPtr->pending = 0;
 	LeaveCriticalSection(&tsdPtr->crit);
     } else if (message != WM_TIMER) {
-	return DefWindowProc(hwnd, message, wParam, lParam);
+	return DefWindowProcW(hwnd, message, wParam, lParam);
     }
 
     /*
@@ -479,7 +479,7 @@ Tcl_WaitForEvent(
 	 * events currently sitting in the queue.
 	 */
 
-	if (!PeekMessage(&msg, NULL, 0, 0, PM_NOREMOVE)) {
+	if (!PeekMessageW(&msg, NULL, 0, 0, PM_NOREMOVE)) {
 	    /*
 	     * Wait for something to happen (a signal from another thread, a
 	     * message, or timeout) or loop servicing asynchronous procedure
@@ -501,12 +501,12 @@ Tcl_WaitForEvent(
 	 * Check to see if there are any messages to process.
 	 */
 
-	if (PeekMessage(&msg, NULL, 0, 0, PM_NOREMOVE)) {
+	if (PeekMessageW(&msg, NULL, 0, 0, PM_NOREMOVE)) {
 	    /*
 	     * Retrieve and dispatch the first message.
 	     */
 
-	    result = GetMessage(&msg, NULL, 0, 0);
+	    result = GetMessageW(&msg, NULL, 0, 0);
 	    if (result == 0) {
 		/*
 		 * We received a request to exit this thread (WM_QUIT), so
@@ -524,7 +524,7 @@ Tcl_WaitForEvent(
 		status = -1;
 	    } else {
 		TranslateMessage(&msg);
-		DispatchMessage(&msg);
+		DispatchMessageW(&msg);
 		status = 1;
 	    }
 	} else {
diff --git a/win/tclWinPipe.c b/win/tclWinPipe.c
index fae5ed3..82a340c 100644
--- a/win/tclWinPipe.c
+++ b/win/tclWinPipe.c
@@ -466,14 +466,14 @@ TempFileName(
 				 * gets stored. */
 {
     const WCHAR *prefix = L"TCL";
-    if (GetTempPath(MAX_PATH, name) != 0) {
-	if (GetTempFileName(name, prefix, 0, name) != 0) {
+    if (GetTempPathW(MAX_PATH, name) != 0) {
+	if (GetTempFileNameW(name, prefix, 0, name) != 0) {
 	    return 1;
 	}
     }
     name[0] = '.';
     name[1] = '\0';
-    return GetTempFileName(name, prefix, 0, name);
+    return GetTempFileNameW(name, prefix, 0, name);
 }
 
 /*
@@ -586,7 +586,7 @@ TclpOpenFile(
 
     flags = 0;
     if (!(mode & O_CREAT)) {
-	flags = GetFileAttributes(nativePath);
+	flags = GetFileAttributesW(nativePath);
 	if (flags == 0xFFFFFFFF) {
 	    flags = 0;
 	}
@@ -602,7 +602,7 @@ TclpOpenFile(
      * Now we get to create the file.
      */
 
-    handle = CreateFile(nativePath, accessMode, shareMode,
+    handle = CreateFileW(nativePath, accessMode, shareMode,
 	    NULL, createMode, flags, NULL);
     Tcl_DStringFree(&ds);
 
@@ -659,7 +659,7 @@ TclpCreateTempFile(
 	return NULL;
     }
 
-    handle = CreateFile(name,
+    handle = CreateFileW(name,
 	    GENERIC_READ | GENERIC_WRITE, 0, NULL, CREATE_ALWAYS,
 	    FILE_ATTRIBUTE_TEMPORARY|FILE_FLAG_DELETE_ON_CLOSE, NULL);
     if (handle == INVALID_HANDLE_VALUE) {
@@ -721,7 +721,7 @@ TclpCreateTempFile(
 
     TclWinConvertError(GetLastError());
     CloseHandle(handle);
-    DeleteFile(name);
+    DeleteFileW(name);
     return NULL;
 }
 
@@ -937,7 +937,7 @@ TclpCreateProcess(
 {
     int result, applType, createFlags;
     Tcl_DString cmdLine;	/* Complete command line (WCHAR). */
-    STARTUPINFO startInfo;
+    STARTUPINFOW startInfo;
     PROCESS_INFORMATION procInfo;
     SECURITY_ATTRIBUTES secAtts;
     HANDLE hProcess, h, inputHandle, outputHandle, errorHandle;
@@ -1048,7 +1048,7 @@ TclpCreateProcess(
 	 * sink.
 	 */
 
-	startInfo.hStdOutput = CreateFile(L"NUL:", GENERIC_WRITE, 0,
+	startInfo.hStdOutput = CreateFileW(L"NUL:", GENERIC_WRITE, 0,
 		&secAtts, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
     } else {
 	DuplicateHandle(hProcess, outputHandle, hProcess,
@@ -1068,7 +1068,7 @@ TclpCreateProcess(
 	 * sink.
 	 */
 
-	startInfo.hStdError = CreateFile(L"NUL:", GENERIC_WRITE, 0,
+	startInfo.hStdError = CreateFileW(L"NUL:", GENERIC_WRITE, 0,
 		&secAtts, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
     } else {
 	DuplicateHandle(hProcess, errorHandle, hProcess, &startInfo.hStdError,
@@ -1134,7 +1134,7 @@ TclpCreateProcess(
 
     BuildCommandLine(execPath, argc, argv, &cmdLine);
 
-    if (CreateProcess(NULL, (WCHAR *) Tcl_DStringValue(&cmdLine),
+    if (CreateProcessW(NULL, (WCHAR *) Tcl_DStringValue(&cmdLine),
 	    NULL, NULL, TRUE, (DWORD) createFlags, NULL, NULL, &startInfo,
 	    &procInfo) == 0) {
 	TclWinConvertError(GetLastError());
@@ -1156,7 +1156,7 @@ TclpCreateProcess(
      * will be created for each process but the previous instances may not be
      * cleaned up. This results in a significant virtual memory loss each time
      * the process is spawned. If there is a WaitForInputIdle() call between
-     * CreateProcess() and CloseHandle(), the problem does not occur." PSS ID
+     * CreateProcessW() and CloseHandle(), the problem does not occur." PSS ID
      * Number: Q124121
      */
 
@@ -1275,7 +1275,7 @@ ApplicationType(
      * is, then try adding .com, .exe, .bat and .cmd, in that order, to the name,
      * looking for an executable.
      *
-     * Using the raw SearchPath() function doesn't do quite what is necessary.
+     * Using the raw SearchPathW() function doesn't do quite what is necessary.
      * If the name of the executable already contains a '.' character, it will
      * not try appending the specified extension when searching (in other
      * words, SearchPath will not find the program "a.b.exe" if the arguments
@@ -1294,7 +1294,7 @@ ApplicationType(
 	Tcl_DStringInit(&ds);
 	nativeName = Tcl_UtfToWCharDString(Tcl_DStringValue(&nameBuf),
 		Tcl_DStringLength(&nameBuf), &ds);
-	found = SearchPath(NULL, nativeName, NULL, MAX_PATH,
+	found = SearchPathW(NULL, nativeName, NULL, MAX_PATH,
 		nativeFullPath, &rest);
 	Tcl_DStringFree(&ds);
 	if (found == 0) {
@@ -1306,7 +1306,7 @@ ApplicationType(
 	 * known type.
 	 */
 
-	attr = GetFileAttributes(nativeFullPath);
+	attr = GetFileAttributesW(nativeFullPath);
 	if ((attr == 0xffffffff) || (attr & FILE_ATTRIBUTE_DIRECTORY)) {
 	    continue;
 	}
@@ -1321,7 +1321,7 @@ ApplicationType(
 	    break;
 	}
 
-	hFile = CreateFile(nativeFullPath,
+	hFile = CreateFileW(nativeFullPath,
 		GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING,
 		FILE_ATTRIBUTE_NORMAL, NULL);
 	if (hFile == INVALID_HANDLE_VALUE) {
@@ -1401,7 +1401,7 @@ ApplicationType(
 	 * application name from the arguments.
 	 */
 
-	GetShortPathName(nativeFullPath, nativeFullPath, MAX_PATH);
+	GetShortPathNameW(nativeFullPath, nativeFullPath, MAX_PATH);
 	Tcl_DStringInit(&ds);
 	strcpy(fullName, Tcl_WCharToUtfDString(nativeFullPath, -1, &ds));
 	Tcl_DStringFree(&ds);
@@ -1415,7 +1415,7 @@ ApplicationType(
  * BuildCommandLine --
  *
  *	The command line arguments are stored in linePtr separated by spaces,
- *	in a form that CreateProcess() understands. Special characters in
+ *	in a form that CreateProcessW() understands. Special characters in
  *	individual arguments from argv[] must be quoted when being stored in
  *	cmdLine.
  *
@@ -1789,7 +1789,7 @@ TclpCreateCommandChannel(
 	 * Start the background reader thread.
 	 */
 
-	infoPtr->readable = CreateEvent(NULL, TRUE, TRUE, NULL);
+	infoPtr->readable = CreateEventW(NULL, TRUE, TRUE, NULL);
 	infoPtr->readThread = CreateThread(NULL, 256, PipeReaderThread,
 	    TclPipeThreadCreateTI(&infoPtr->readTI, infoPtr, infoPtr->readable),
 	    0, NULL);
@@ -1804,7 +1804,7 @@ TclpCreateCommandChannel(
 	 * Start the background writer thread.
 	 */
 
-	infoPtr->writable = CreateEvent(NULL, TRUE, TRUE, NULL);
+	infoPtr->writable = CreateEventW(NULL, TRUE, TRUE, NULL);
 	infoPtr->writeThread = CreateThread(NULL, 256, PipeWriterThread,
 	    TclPipeThreadCreateTI(&infoPtr->writeTI, infoPtr, infoPtr->writable),
 	    0, NULL);
@@ -3207,7 +3207,7 @@ TclpOpenTemporaryFile(
     }
 
     namePtr = (char *) name;
-    length = GetTempPath(MAX_PATH, name);
+    length = GetTempPathW(MAX_PATH, name);
     if (length == 0) {
 	goto gotError;
     }
@@ -3242,7 +3242,7 @@ TclpOpenTemporaryFile(
 	memcpy(namePtr, Tcl_DStringValue(&buf), Tcl_DStringLength(&buf) + 1);
 	Tcl_DStringFree(&buf);
 
-	handle = CreateFile(name,
+	handle = CreateFileW(name,
 		GENERIC_READ|GENERIC_WRITE, 0, NULL, CREATE_NEW, flags, NULL);
     } while (handle == INVALID_HANDLE_VALUE
 	    && --counter2 > 0
@@ -3291,7 +3291,7 @@ TclPipeThreadCreateTI(
 #else
     pipeTI = Tcl_Alloc(sizeof(TclPipeThreadInfo));
 #endif /* !_PTI_USE_CKALLOC */
-    pipeTI->evControl = CreateEvent(NULL, FALSE, FALSE, NULL);
+    pipeTI->evControl = CreateEventW(NULL, FALSE, FALSE, NULL);
     pipeTI->state = PTI_STATE_IDLE;
     pipeTI->clientData = clientData;
     pipeTI->evWakeUp = wakeEvent;
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);
diff --git a/win/tclWinSerial.c b/win/tclWinSerial.c
index fed1c5e..cc35f07 100644
--- a/win/tclWinSerial.c
+++ b/win/tclWinSerial.c
@@ -1291,7 +1291,7 @@ SerialWriterThread(
 	buf = infoPtr->writeBuf;
 	toWrite = infoPtr->toWrite;
 
-	myWrite.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
+	myWrite.hEvent = CreateEventW(NULL, TRUE, FALSE, NULL);
 
 	/*
 	 * Loop until all of the bytes are written or an error occurs.
@@ -1403,7 +1403,7 @@ TclWinSerialOpen(
      * If an open channel is specified, close it
      */
 
-    if ( handle != INVALID_HANDLE_VALUE && CloseHandle(handle) == FALSE) {
+    if (handle != INVALID_HANDLE_VALUE && CloseHandle(handle) == FALSE) {
 	return INVALID_HANDLE_VALUE;
     }
 
@@ -1413,7 +1413,7 @@ TclWinSerialOpen(
      * finished
      */
 
-    handle = CreateFile(name, access, 0, 0, OPEN_EXISTING,
+    handle = CreateFileW(name, access, 0, 0, OPEN_EXISTING,
 	    FILE_FLAG_OVERLAPPED, 0);
 
     return handle;
@@ -1486,15 +1486,15 @@ TclWinOpenSerialChannel(
 
     InitializeCriticalSection(&infoPtr->csWrite);
     if (permissions & TCL_READABLE) {
-	infoPtr->osRead.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
+	infoPtr->osRead.hEvent = CreateEventW(NULL, TRUE, FALSE, NULL);
     }
     if (permissions & TCL_WRITABLE) {
 	/*
 	 * Initially the channel is writable and the writeThread is idle.
 	 */
 
-	infoPtr->osWrite.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
-	infoPtr->evWritable = CreateEvent(NULL, TRUE, TRUE, NULL);
+	infoPtr->osWrite.hEvent = CreateEventW(NULL, TRUE, FALSE, NULL);
+	infoPtr->evWritable = CreateEventW(NULL, TRUE, TRUE, NULL);
 	infoPtr->writeThread = CreateThread(NULL, 256, SerialWriterThread,
 		TclPipeThreadCreateTI(&infoPtr->writeTI, infoPtr,
 			infoPtr->evWritable), 0, NULL);
@@ -1671,7 +1671,7 @@ SerialSetOptionProc(
 	}
 	Tcl_DStringInit(&ds);
 	native = Tcl_UtfToWCharDString(value, -1, &ds);
-	result = BuildCommDCB(native, &dcb);
+	result = BuildCommDCBW(native, &dcb);
 	Tcl_DStringFree(&ds);
 
 	if (result == FALSE) {
diff --git a/win/tclWinSock.c b/win/tclWinSock.c
index 1679bbe..77929f0 100644
--- a/win/tclWinSock.c
+++ b/win/tclWinSock.c
@@ -235,7 +235,7 @@ typedef struct {
 } ThreadSpecificData;
 
 static Tcl_ThreadDataKey dataKey;
-static WNDCLASS windowClass;
+static WNDCLASSW windowClass;
 
 /*
  * Static routines for this file:
@@ -363,17 +363,17 @@ InitializeHostName(
     size_t *lengthPtr,
     Tcl_Encoding *encodingPtr)
 {
-    WCHAR tbuf[MAX_COMPUTERNAME_LENGTH + 1];
+    WCHAR wbuf[MAX_COMPUTERNAME_LENGTH + 1];
     DWORD length = MAX_COMPUTERNAME_LENGTH + 1;
     Tcl_DString ds;
 
     Tcl_DStringInit(&ds);
-    if (GetComputerName(tbuf, &length) != 0) {
+    if (GetComputerNameW(wbuf, &length) != 0) {
 	/*
 	 * Convert string from native to UTF then change to lowercase.
 	 */
 
-	Tcl_UtfToLower(Tcl_WCharToUtfDString(tbuf, -1, &ds));
+	Tcl_UtfToLower(Tcl_WCharToUtfDString(wbuf, -1, &ds));
 
     } else {
 	if (TclpHasSockets(NULL) == TCL_OK) {
@@ -2504,7 +2504,7 @@ InitSockets(void)
 	windowClass.hIcon = NULL;
 	windowClass.hCursor = NULL;
 
-	if (!RegisterClass(&windowClass)) {
+	if (!RegisterClassW(&windowClass)) {
 	    TclWinConvertError(GetLastError());
 	    goto initFailure;
 	}
@@ -2629,7 +2629,7 @@ SocketExitHandler(
      */
 
     TclpFinalizeSockets();
-    UnregisterClass(className, TclWinGetTclInstance());
+    UnregisterClassW(className, TclWinGetTclInstance());
     initialized = 0;
     Tcl_MutexUnlock(&socketMutex);
 }
@@ -3176,7 +3176,7 @@ SocketThread(
      * Create a dummy window receiving socket events.
      */
 
-    tsdPtr->hwnd = CreateWindow(className, className, WS_TILED, 0, 0, 0, 0,
+    tsdPtr->hwnd = CreateWindowW(className, className, WS_TILED, 0, 0, 0, 0,
 	    NULL, NULL, windowClass.hInstance, arg);
 
     /*
@@ -3199,8 +3199,8 @@ SocketThread(
      * PostMessage(SOCKET_TERMINATE) in TclpFinalizeSockets().
      */
 
-    while (GetMessage(&msg, NULL, 0, 0) > 0) {
-	DispatchMessage(&msg);
+    while (GetMessageW(&msg, NULL, 0, 0) > 0) {
+	DispatchMessageW(&msg);
     }
 
     /*
@@ -3245,14 +3245,14 @@ SocketProc(
     TcpFdList *fds = NULL;
     ThreadSpecificData *tsdPtr = (ThreadSpecificData *)
 #ifdef _WIN64
-	    GetWindowLongPtr(hwnd, GWLP_USERDATA);
+	    GetWindowLongPtrW(hwnd, GWLP_USERDATA);
 #else
 	    GetWindowLong(hwnd, GWL_USERDATA);
 #endif
 
     switch (message) {
     default:
-	return DefWindowProc(hwnd, message, wParam, lParam);
+	return DefWindowProcW(hwnd, message, wParam, lParam);
 	break;
 
     case WM_CREATE:
diff --git a/win/tclWinTest.c b/win/tclWinTest.c
index 56aedbc..d43ba74 100644
--- a/win/tclWinTest.c
+++ b/win/tclWinTest.c
@@ -136,7 +136,7 @@ TesteventloopCmd(
 	while (!done) {
 	    MSG msg;
 
-	    if (!GetMessage(&msg, NULL, 0, 0)) {
+	    if (!GetMessageW(&msg, NULL, 0, 0)) {
 		/*
 		 * The application is exiting, so repost the quit message and
 		 * start unwinding.
@@ -146,7 +146,7 @@ TesteventloopCmd(
 		break;
 	    }
 	    TranslateMessage(&msg);
-	    DispatchMessage(&msg);
+	    DispatchMessageW(&msg);
 	}
 	(void) Tcl_SetServiceMode(oldMode);
 	framePtr = oldFramePtr;
diff --git a/win/tclWinThrd.c b/win/tclWinThrd.c
index 199d685..3e8b7d5 100644
--- a/win/tclWinThrd.c
+++ b/win/tclWinThrd.c
@@ -682,7 +682,7 @@ Tcl_ConditionWait(
 	 */
 
 	if (tsdPtr->flags == WIN_THREAD_UNINIT) {
-	    tsdPtr->condEvent = CreateEvent(NULL, TRUE /* manual reset */,
+	    tsdPtr->condEvent = CreateEventW(NULL, TRUE /* manual reset */,
 		    FALSE /* non signaled */, NULL);
 	    tsdPtr->nextPtr = NULL;
 	    tsdPtr->prevPtr = NULL;
diff --git a/win/tclWinTime.c b/win/tclWinTime.c
index 454956d..cce2776 100644
--- a/win/tclWinTime.c
+++ b/win/tclWinTime.c
@@ -520,8 +520,8 @@ NativeGetMicroseconds(void)
 		DWORD id;
 
 		InitializeCriticalSection(&timeInfo.cs);
-		timeInfo.readyEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
-		timeInfo.exitEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
+		timeInfo.readyEvent = CreateEventW(NULL, FALSE, FALSE, NULL);
+		timeInfo.exitEvent = CreateEventW(NULL, FALSE, FALSE, NULL);
 		timeInfo.calibrationThread = CreateThread(NULL, 256,
 			CalibrationThread, (LPVOID) NULL, 0, &id);
 		SetThreadPriority(timeInfo.calibrationThread,