Merge 8.7

21 files changed, 320 insertions, 344 deletions

diff --git a/doc/Encoding.3 b/doc/Encoding.3
index c3161e1..497683d 100644
--- a/doc/Encoding.3
+++ b/doc/Encoding.3
@@ -8,7 +8,7 @@
 .so man.macros
 .BS
 .SH NAME
-Tcl_GetEncoding, Tcl_FreeEncoding, Tcl_GetEncodingFromObj, Tcl_ExternalToUtfDString, Tcl_ExternalToUtf, Tcl_UtfToExternalDString, Tcl_UtfToExternal, Tcl_WinTCharToUtf, Tcl_WinUtfToTChar, Tcl_GetEncodingName, Tcl_SetSystemEncoding, Tcl_GetEncodingNameFromEnvironment, Tcl_GetEncodingNames, Tcl_CreateEncoding, Tcl_GetEncodingSearchPath, Tcl_SetEncodingSearchPath \- procedures for creating and using encodings
+Tcl_GetEncoding, Tcl_FreeEncoding, Tcl_GetEncodingFromObj, Tcl_ExternalToUtfDString, Tcl_ExternalToUtf, Tcl_UtfToExternalDString, Tcl_UtfToExternal, Tcl_GetEncodingName, Tcl_SetSystemEncoding, Tcl_GetEncodingNameFromEnvironment, Tcl_GetEncodingNames, Tcl_CreateEncoding, Tcl_GetEncodingSearchPath, Tcl_SetEncodingSearchPath \- procedures for creating and using encodings
 .SH SYNOPSIS
 .nf
 \fB#include <tcl.h>\fR
@@ -36,12 +36,6 @@ int
 \fBTcl_UtfToExternal\fR(\fIinterp, encoding, src, srcLen, flags, statePtr,
                   dst, dstLen, srcReadPtr, dstWrotePtr, dstCharsPtr\fR)
 .sp
-char *
-\fBTcl_WinTCharToUtf\fR(\fItsrc, srcLen, dstPtr\fR)
-.sp
-TCHAR *
-\fBTcl_WinUtfToTChar\fR(\fIsrc, srcLen, dstPtr\fR)
-.sp
 const char *
 \fBTcl_GetEncodingName\fR(\fIencoding\fR)
 .sp
@@ -79,7 +73,7 @@ Points to storage where encoding token is to be written.
 .AP "const char" *src in
 For the \fBTcl_ExternalToUtf\fR functions, an array of bytes in the
 specified encoding that are to be converted to UTF-8.  For the
-\fBTcl_UtfToExternal\fR and \fBTcl_WinUtfToTChar\fR functions, an array of
+\fBTcl_UtfToExternal\fR function, an array of
 UTF-8 characters to be converted to the specified encoding.
 .AP "const TCHAR" *tsrc in
 An array of Windows TCHAR characters to convert to UTF-8.
@@ -249,12 +243,6 @@ is filled with the corresponding number of bytes that were stored in
 \fIdst\fR.  The return values are the same as the return values for
 \fBTcl_ExternalToUtf\fR.
 .PP
-\fBTcl_WinUtfToTChar\fR and \fBTcl_WinTCharToUtf\fR are
-Windows-only convenience
-functions for converting between UTF-8 and Windows strings
-based on the TCHAR type which is by convention
-a Unicode character on Windows NT.
-.PP
 \fBTcl_GetEncodingName\fR is roughly the inverse of \fBTcl_GetEncoding\fR.
 Given an \fIencoding\fR, the return value is the \fIname\fR argument that
 was used to create the encoding.  The string returned by
diff --git a/doc/Utf.3 b/doc/Utf.3
index 94f6f4e..ba1a2a7 100644
--- a/doc/Utf.3
+++ b/doc/Utf.3
@@ -8,7 +8,7 @@
 .so man.macros
 .BS
 .SH NAME
-Tcl_UniChar, Tcl_UniCharToUtf, Tcl_UtfToUniChar, Tcl_UniCharToUtfDString, Tcl_UtfToUniCharDString, Tcl_UniCharLen, Tcl_UniCharNcmp, Tcl_UniCharNcasecmp, Tcl_UniCharCaseMatch, Tcl_UtfNcmp, Tcl_UtfNcasecmp, Tcl_UtfCharComplete, Tcl_NumUtfChars, Tcl_UtfFindFirst, Tcl_UtfFindLast, Tcl_UtfNext, Tcl_UtfPrev, Tcl_UniCharAtIndex, Tcl_UtfAtIndex, Tcl_UtfBackslash \- routines for manipulating UTF-8 strings
+Tcl_UniChar, Tcl_UniCharToUtf, Tcl_UtfToUniChar, Tcl_UtfToChar16, Tcl_UtfToWChar, Tcl_UniCharToUtfDString, Tcl_UtfToUniCharDString, Tcl_WCharToUtfDString, Tcl_UtfToWCharDString, Tcl_Char16ToUtfDString, Tcl_UtfToChar16DString, Tcl_UniCharLen, Tcl_UniCharNcmp, Tcl_UniCharNcasecmp, Tcl_UniCharCaseMatch, Tcl_UtfNcmp, Tcl_UtfNcasecmp, Tcl_UtfCharComplete, Tcl_NumUtfChars, Tcl_UtfFindFirst, Tcl_UtfFindLast, Tcl_UtfNext, Tcl_UtfPrev, Tcl_UniCharAtIndex, Tcl_UtfAtIndex, Tcl_UtfBackslash \- routines for manipulating UTF-8 strings
 .SH SYNOPSIS
 .nf
 \fB#include <tcl.h>\fR
@@ -21,12 +21,30 @@ int
 int
 \fBTcl_UtfToUniChar\fR(\fIsrc, chPtr\fR)
 .sp
+int
+\fBTcl_UtfToChar16\fR(\fIsrc, uPtr\fR)
+.sp
+int
+\fBTcl_UtfToWChar\fR(\fIsrc, wPtr\fR)
+.sp
 char *
 \fBTcl_UniCharToUtfDString\fR(\fIuniStr, uniLength, dsPtr\fR)
 .sp
+char *
+\fBTcl_Char16ToUtfDString\fR(\fIuStr, uniLength, dsPtr\fR)
+.sp
+char *
+\fBTcl_WCharToUtfDString\fR(\fIwStr, uniLength, dsPtr\fR)
+.sp
 Tcl_UniChar *
 \fBTcl_UtfToUniCharDString\fR(\fIsrc, length, dsPtr\fR)
 .sp
+unsigned short *
+\fBTcl_UtfToChar16DString\fR(\fIsrc, length, dsPtr\fR)
+.sp
+wchar_t *
+\fBTcl_UtfToWCharDString\fR(\fIsrc, length, dsPtr\fR)
+.sp
 int
 \fBTcl_UniCharLen\fR(\fIuniStr\fR)
 .sp
@@ -80,6 +98,10 @@ Buffer in which the UTF-8 representation of the Tcl_UniChar is stored.  At most
 The Unicode character to be converted or examined.
 .AP Tcl_UniChar *chPtr out
 Filled with the Tcl_UniChar represented by the head of the UTF-8 string.
+.AP unsigned short *uPtr out
+Filled with the utf-16 represented by the head of the UTF-8 string.
+.AP wchar_t *wPtr out
+Filled with the wchar_t represented by the head of the UTF-8 string.
 .AP "const char" *src in
 Pointer to a UTF-8 string.
 .AP "const char" *cs in
@@ -94,9 +116,13 @@ A null-terminated Unicode string.
 A null-terminated Unicode string.
 .AP "const Tcl_UniChar" *uniPattern in
 A null-terminated Unicode string.
+.AP "const unsigned short" *uStr in
+A null-terminated UTF-16 string.
+.AP "const wchar_t" *wStr in
+A null-terminated wchar_t string.
 .AP size_t length in
 The length of the UTF-8 string in bytes (not UTF-8 characters).  If
-TCL_AUTO_LENGTH, all bytes up to the first null byte are used.
+negative, all bytes up to the first null byte are used.
 .AP size_t uniLength in
 The length of the Unicode string in characters.
 .AP "Tcl_DString" *dsPtr in/out
@@ -118,11 +144,10 @@ case-insensitive (1).
 
 .SH DESCRIPTION
 .PP
-These routines convert between UTF-8 strings and Unicode characters.  An
-Unicode character represented as an unsigned, fixed-size
-quantity.  A UTF-8 character is a Unicode character represented as
-a varying-length sequence of up to \fBTCL_UTF_MAX\fR bytes.  A multibyte UTF-8
-sequence consists of a lead byte followed by some number of trail bytes.
+These routines convert between UTF-8 strings and Unicode/Utf-16 characters.
+A UTF-8 character is a Unicode character represented as a varying-length
+sequence of up to \fBTCL_UTF_MAX\fR bytes.  A multibyte UTF-8 sequence
+consists of a lead byte followed by some number of trail bytes.
 .PP
 \fBTCL_UTF_MAX\fR is the maximum number of bytes that it takes to
 represent one Unicode character in the UTF-8 representation.
@@ -150,7 +175,6 @@ byte of \fIsrc\fR in \fI*chPtr\fR as a Tcl_UniChar between 0x00A0 and
 .PP
 \fBTcl_UniCharToUtfDString\fR converts the given Unicode string
 to UTF-8, storing the result in a previously initialized \fBTcl_DString\fR.
-You must specify \fIuniLength\fR, the length of the given Unicode string.
 The return value is a pointer to the UTF-8 representation of the
 Unicode string.  Storage for the return value is appended to the
 end of the \fBTcl_DString\fR.
diff --git a/generic/tcl.decls b/generic/tcl.decls
index f72d57e..8b16a1b 100644
--- a/generic/tcl.decls
+++ b/generic/tcl.decls
@@ -1242,7 +1242,7 @@ declare 335 {
     int Tcl_UtfToTitle(char *src)
 }
 declare 336 {
-    int Tcl_UtfToUniChar(const char *src, Tcl_UniChar *chPtr)
+    int Tcl_UtfToChar16(const char *src, unsigned short *chPtr)
 }
 declare 337 {
     int Tcl_UtfToUpper(char *src)
@@ -1299,11 +1299,11 @@ declare 353 {
 	    size_t numChars)
 }
 declare 354 {
-    char *Tcl_UniCharToUtfDString(const Tcl_UniChar *uniStr,
+    char *Tcl_Char16ToUtfDString(const unsigned short *uniStr,
 	    size_t uniLength, Tcl_DString *dsPtr)
 }
 declare 355 {
-    Tcl_UniChar *Tcl_UtfToUniCharDString(const char *src,
+    unsigned short *Tcl_UtfToChar16DString(const char *src,
 	    size_t length, Tcl_DString *dsPtr)
 }
 declare 356 {
@@ -2444,6 +2444,19 @@ declare 645 {
 	    size_t endValue, size_t *indexPtr)
 }
 
+# TIP #548
+declare 646 {
+    int Tcl_UtfToUniChar(const char *src, int *chPtr)
+}
+declare 647 {
+    char *Tcl_UniCharToUtfDString(const int *uniStr,
+	    size_t uniLength, Tcl_DString *dsPtr)
+}
+declare 648 {
+    int *Tcl_UtfToUniCharDString(const char *src,
+	    size_t length, Tcl_DString *dsPtr)
+}
+
 # ----- BASELINE -- FOR -- 8.7.0 ----- #
 
 ##############################################################################
@@ -2460,14 +2473,14 @@ interface tclPlat
 ################################
 # Windows specific functions
 
-# Added in Tcl 8.1
+# Added in Tcl 8.1, Removed in Tcl 9.0 (converted to macro)
 
-declare 0 win {
-    TCHAR *Tcl_WinUtfToTChar(const char *str, size_t len, Tcl_DString *dsPtr)
-}
-declare 1 win {
-    char *Tcl_WinTCharToUtf(const TCHAR *str, size_t len, Tcl_DString *dsPtr)
-}
+#declare 0 win {
+#    TCHAR *Tcl_WinUtfToTChar(const char *str, size_t len, Tcl_DString *dsPtr)
+#}
+#declare 1 win {
+#    char *Tcl_WinTCharToUtf(const TCHAR *str, size_t len, Tcl_DString *dsPtr)
+#}
 
 ################################
 # Mac OS X specific functions
diff --git a/generic/tcl.h b/generic/tcl.h
index 8017dd0..37a11ff 100644
--- a/generic/tcl.h
+++ b/generic/tcl.h
@@ -1984,7 +1984,7 @@ typedef struct Tcl_EncodingType {
 
 #if TCL_UTF_MAX > 4
     /*
-     * unsigned int isn't 100% accurate as it should be a strict 4-byte value
+     * int isn't 100% accurate as it should be a strict 4-byte value
      * (perhaps wchar_t). 64-bit systems may have troubles. The size of this
      * value must be reflected correctly in regcustom.h and
      * in tclEncoding.c.
@@ -1992,7 +1992,7 @@ typedef struct Tcl_EncodingType {
      * XXX: string rep that Tcl_UniChar represents.  Changing the size
      * XXX: of Tcl_UniChar is /not/ supported.
      */
-typedef unsigned int Tcl_UniChar;
+typedef int Tcl_UniChar;
 #else
 typedef unsigned short Tcl_UniChar;
 #endif
diff --git a/generic/tclDecls.h b/generic/tclDecls.h
index 35ad3fa..5d8fdd6 100644
--- a/generic/tclDecls.h
+++ b/generic/tclDecls.h
@@ -910,7 +910,8 @@ EXTERN int		Tcl_UtfToLower(char *src);
 /* 335 */
 EXTERN int		Tcl_UtfToTitle(char *src);
 /* 336 */
-EXTERN int		Tcl_UtfToUniChar(const char *src, Tcl_UniChar *chPtr);
+EXTERN int		Tcl_UtfToChar16(const char *src,
+				unsigned short *chPtr);
 /* 337 */
 EXTERN int		Tcl_UtfToUpper(char *src);
 /* 338 */
@@ -946,10 +947,10 @@ EXTERN size_t		Tcl_UniCharLen(const Tcl_UniChar *uniStr);
 EXTERN int		Tcl_UniCharNcmp(const Tcl_UniChar *ucs,
 				const Tcl_UniChar *uct, size_t numChars);
 /* 354 */
-EXTERN char *		Tcl_UniCharToUtfDString(const Tcl_UniChar *uniStr,
+EXTERN char *		Tcl_Char16ToUtfDString(const unsigned short *uniStr,
 				size_t uniLength, Tcl_DString *dsPtr);
 /* 355 */
-EXTERN Tcl_UniChar *	Tcl_UtfToUniCharDString(const char *src,
+EXTERN unsigned short *	 Tcl_UtfToChar16DString(const char *src,
 				size_t length, Tcl_DString *dsPtr);
 /* 356 */
 EXTERN Tcl_RegExp	Tcl_GetRegExpFromObj(Tcl_Interp *interp,
@@ -1757,6 +1758,14 @@ EXTERN int		Tcl_LinkArray(Tcl_Interp *interp,
 EXTERN int		Tcl_GetIntForIndex(Tcl_Interp *interp,
 				Tcl_Obj *objPtr, size_t endValue,
 				size_t *indexPtr);
+/* 646 */
+EXTERN int		Tcl_UtfToUniChar(const char *src, int *chPtr);
+/* 647 */
+EXTERN char *		Tcl_UniCharToUtfDString(const int *uniStr,
+				size_t uniLength, Tcl_DString *dsPtr);
+/* 648 */
+EXTERN int *		Tcl_UtfToUniCharDString(const char *src,
+				size_t length, Tcl_DString *dsPtr);
 
 typedef struct {
     const struct TclPlatStubs *tclPlatStubs;
@@ -2128,7 +2137,7 @@ typedef struct TclStubs {
     char * (*tcl_UtfToExternalDString) (Tcl_Encoding encoding, const char *src, size_t srcLen, Tcl_DString *dsPtr); /* 333 */
     int (*tcl_UtfToLower) (char *src); /* 334 */
     int (*tcl_UtfToTitle) (char *src); /* 335 */
-    int (*tcl_UtfToUniChar) (const char *src, Tcl_UniChar *chPtr); /* 336 */
+    int (*tcl_UtfToChar16) (const char *src, unsigned short *chPtr); /* 336 */
     int (*tcl_UtfToUpper) (char *src); /* 337 */
     size_t (*tcl_WriteChars) (Tcl_Channel chan, const char *src, size_t srcLen); /* 338 */
     size_t (*tcl_WriteObj) (Tcl_Channel chan, Tcl_Obj *objPtr); /* 339 */
@@ -2146,8 +2155,8 @@ typedef struct TclStubs {
     int (*tcl_UniCharIsWordChar) (int ch); /* 351 */
     size_t (*tcl_UniCharLen) (const Tcl_UniChar *uniStr); /* 352 */
     int (*tcl_UniCharNcmp) (const Tcl_UniChar *ucs, const Tcl_UniChar *uct, size_t numChars); /* 353 */
-    char * (*tcl_UniCharToUtfDString) (const Tcl_UniChar *uniStr, size_t uniLength, Tcl_DString *dsPtr); /* 354 */
-    Tcl_UniChar * (*tcl_UtfToUniCharDString) (const char *src, size_t length, Tcl_DString *dsPtr); /* 355 */
+    char * (*tcl_Char16ToUtfDString) (const unsigned short *uniStr, size_t uniLength, Tcl_DString *dsPtr); /* 354 */
+    unsigned short * (*tcl_UtfToChar16DString) (const char *src, size_t length, Tcl_DString *dsPtr); /* 355 */
     Tcl_RegExp (*tcl_GetRegExpFromObj) (Tcl_Interp *interp, Tcl_Obj *patObj, int flags); /* 356 */
     void (*reserved357)(void);
     void (*tcl_FreeParse) (Tcl_Parse *parsePtr); /* 358 */
@@ -2438,6 +2447,9 @@ typedef struct TclStubs {
     int (*tcl_IsShared) (Tcl_Obj *objPtr); /* 643 */
     int (*tcl_LinkArray) (Tcl_Interp *interp, const char *varName, void *addr, int type, size_t size); /* 644 */
     int (*tcl_GetIntForIndex) (Tcl_Interp *interp, Tcl_Obj *objPtr, size_t endValue, size_t *indexPtr); /* 645 */
+    int (*tcl_UtfToUniChar) (const char *src, int *chPtr); /* 646 */
+    char * (*tcl_UniCharToUtfDString) (const int *uniStr, size_t uniLength, Tcl_DString *dsPtr); /* 647 */
+    int * (*tcl_UtfToUniCharDString) (const char *src, size_t length, Tcl_DString *dsPtr); /* 648 */
 } TclStubs;
 
 extern const TclStubs *tclStubsPtr;
@@ -3095,8 +3107,8 @@ extern const TclStubs *tclStubsPtr;
 	(tclStubsPtr->tcl_UtfToLower) /* 334 */
 #define Tcl_UtfToTitle \
 	(tclStubsPtr->tcl_UtfToTitle) /* 335 */
-#define Tcl_UtfToUniChar \
-	(tclStubsPtr->tcl_UtfToUniChar) /* 336 */
+#define Tcl_UtfToChar16 \
+	(tclStubsPtr->tcl_UtfToChar16) /* 336 */
 #define Tcl_UtfToUpper \
 	(tclStubsPtr->tcl_UtfToUpper) /* 337 */
 #define Tcl_WriteChars \
@@ -3129,10 +3141,10 @@ extern const TclStubs *tclStubsPtr;
 	(tclStubsPtr->tcl_UniCharLen) /* 352 */
 #define Tcl_UniCharNcmp \
 	(tclStubsPtr->tcl_UniCharNcmp) /* 353 */
-#define Tcl_UniCharToUtfDString \
-	(tclStubsPtr->tcl_UniCharToUtfDString) /* 354 */
-#define Tcl_UtfToUniCharDString \
-	(tclStubsPtr->tcl_UtfToUniCharDString) /* 355 */
+#define Tcl_Char16ToUtfDString \
+	(tclStubsPtr->tcl_Char16ToUtfDString) /* 354 */
+#define Tcl_UtfToChar16DString \
+	(tclStubsPtr->tcl_UtfToChar16DString) /* 355 */
 #define Tcl_GetRegExpFromObj \
 	(tclStubsPtr->tcl_GetRegExpFromObj) /* 356 */
 /* Slot 357 is reserved */
@@ -3706,6 +3718,12 @@ extern const TclStubs *tclStubsPtr;
 	(tclStubsPtr->tcl_LinkArray) /* 644 */
 #define Tcl_GetIntForIndex \
 	(tclStubsPtr->tcl_GetIntForIndex) /* 645 */
+#define Tcl_UtfToUniChar \
+	(tclStubsPtr->tcl_UtfToUniChar) /* 646 */
+#define Tcl_UniCharToUtfDString \
+	(tclStubsPtr->tcl_UniCharToUtfDString) /* 647 */
+#define Tcl_UtfToUniCharDString \
+	(tclStubsPtr->tcl_UtfToUniCharDString) /* 648 */
 
 #endif /* defined(USE_TCL_STUBS) */
 
@@ -3855,6 +3873,36 @@ extern const TclStubs *tclStubsPtr;
 #define Tcl_BackgroundError(interp)	Tcl_BackgroundException((interp), TCL_ERROR)
 #define Tcl_StringMatch(str, pattern) Tcl_StringCaseMatch((str), (pattern), 0)
 
+#if TCL_UTF_MAX <= 4
+#   undef Tcl_UniCharToUtfDString
+#   define Tcl_UniCharToUtfDString Tcl_Char16ToUtfDString
+#   undef Tcl_UtfToUniCharDString
+#   define Tcl_UtfToUniCharDString Tcl_UtfToChar16DString
+#   undef Tcl_UtfToUniChar
+#   define Tcl_UtfToUniChar Tcl_UtfToChar16
+#endif
+#if defined(USE_TCL_STUBS)
+#   define Tcl_WCharToUtfDString (sizeof(wchar_t) != sizeof(short) \
+		? (char *(*)(const wchar_t *, size_t, Tcl_DString *))tclStubsPtr->tcl_UniCharToUtfDString \
+		: (char *(*)(const wchar_t *, size_t, Tcl_DString *))Tcl_Char16ToUtfDString)
+#   define Tcl_UtfToWCharDString (sizeof(wchar_t) != sizeof(short) \
+		? (wchar_t *(*)(const char *, size_t, Tcl_DString *))tclStubsPtr->tcl_UtfToUniCharDString \
+		: (wchar_t *(*)(const char *, size_t, Tcl_DString *))Tcl_UtfToChar16DString)
+#   define Tcl_UtfToWChar (sizeof(wchar_t) != sizeof(short) \
+		? (int (*)(const char *, wchar_t *))tclStubsPtr->tcl_UtfToChar16 \
+		: (int (*)(const char *, wchar_t *))Tcl_UtfToUniChar)
+#else
+#   define Tcl_WCharToUtfDString (sizeof(wchar_t) != sizeof(short) \
+		? (char *(*)(const wchar_t *, size_t, Tcl_DString *))Tcl_UniCharToUtfDString \
+		: (char *(*)(const wchar_t *, size_t, Tcl_DString *))Tcl_Char16ToUtfDString)
+#   define Tcl_UtfToWCharDString (sizeof(wchar_t) != sizeof(short) \
+		? (wchar_t *(*)(const char *, size_t, Tcl_DString *))Tcl_UtfToUniCharDString \
+		: (wchar_t *(*)(const char *, size_t, Tcl_DString *))Tcl_UtfToChar16DString)
+#   define Tcl_UtfToWChar (sizeof(wchar_t) != sizeof(short) \
+		? (int (*)(const char *, wchar_t *))Tcl_UtfToChar16 \
+		: (int (*)(const char *, wchar_t *))Tcl_UtfToUniChar)
+#endif
+
 /*
  * Deprecated Tcl procedures:
  */
diff --git a/generic/tclIOSock.c b/generic/tclIOSock.c
index db124fb..531c38b 100644
--- a/generic/tclIOSock.c
+++ b/generic/tclIOSock.c
@@ -30,11 +30,12 @@ gai_strerror(
     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
 
     if (tsdPtr->initialized) {
-	Tcl_DStringFree(&tsdPtr->errorMsg);
+	Tcl_DStringSetLength(&tsdPtr->errorMsg, 0);
     } else {
+	Tcl_DStringInit(&tsdPtr->errorMsg);
 	tsdPtr->initialized = 1;
     }
-    Tcl_WinTCharToUtf(gai_strerrorW(code), -1, &tsdPtr->errorMsg);
+    Tcl_WCharToUtfDString(gai_strerrorW(code), -1, &tsdPtr->errorMsg);
     return Tcl_DStringValue(&tsdPtr->errorMsg);
 }
 #endif
diff --git a/generic/tclInt.h b/generic/tclInt.h
index 8afd63e..7bb6170 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -3172,17 +3172,6 @@ MODULE_SCOPE const char*TclGetCommandTypeName(Tcl_Command command);
 MODULE_SCOPE void	TclRegisterCommandTypeName(
 			    Tcl_ObjCmdProc *implementationProc,
 			    const char *nameStr);
-#if (TCL_UTF_MAX > 4) && (defined(__CYGWIN__) || defined(_WIN32))
-MODULE_SCOPE int TclUtfToWChar(const char *src, WCHAR *chPtr);
-MODULE_SCOPE char *	TclWCharToUtfDString(const WCHAR *uniStr,
-			    size_t uniLength, Tcl_DString *dsPtr);
-MODULE_SCOPE WCHAR * TclUtfToWCharDString(const char *src,
-			    size_t length, Tcl_DString *dsPtr);
-#else
-#   define TclUtfToWChar TclUtfToUniChar
-#   define TclWCharToUtfDString Tcl_UniCharToUtfDString
-#   define TclUtfToWCharDString Tcl_UtfToUniCharDString
-#endif
 MODULE_SCOPE int	TclUtfCmp(const char *cs, const char *ct);
 MODULE_SCOPE int	TclUtfCasecmp(const char *cs, const char *ct);
 MODULE_SCOPE size_t	TclUtfCount(int ch);
@@ -4576,10 +4565,17 @@ MODULE_SCOPE void	TclDbInitNewObj(Tcl_Obj *objPtr, const char *file,
  *----------------------------------------------------------------
  */
 
+#if TCL_UTF_MAX > 4
 #define TclUtfToUniChar(str, chPtr) \
 	((((unsigned char) *(str)) < 0x80) ?		\
 	    ((*(chPtr) = (unsigned char) *(str)), 1)	\
 	    : Tcl_UtfToUniChar(str, chPtr))
+#else
+#define TclUtfToUniChar(str, chPtr) \
+	((((unsigned char) *(str)) < 0x80) ?		\
+	    ((*(chPtr) = (unsigned char) *(str)), 1)	\
+	    : Tcl_UtfToChar16(str, chPtr))
+#endif
 
 /*
  *----------------------------------------------------------------
diff --git a/generic/tclMain.c b/generic/tclMain.c
index 31e6438..e5a4408 100644
--- a/generic/tclMain.c
+++ b/generic/tclMain.c
@@ -70,10 +70,8 @@ NewNativeObj(
     Tcl_DString ds;
 
 #ifdef UNICODE
-    if (length != TCL_AUTO_LENGTH) {
-	length *= sizeof(WCHAR);
-    }
-    Tcl_WinTCharToUtf(string, length, &ds);
+    Tcl_DStringInit(&ds);
+    Tcl_WCharToUtfDString(string, length, &ds);
 #else
     Tcl_ExternalToUtfDString(NULL, (char *) string, length, &ds);
 #endif
diff --git a/generic/tclPlatDecls.h b/generic/tclPlatDecls.h
index 7218490..b1a874f 100644
--- a/generic/tclPlatDecls.h
+++ b/generic/tclPlatDecls.h
@@ -50,14 +50,6 @@ extern "C" {
  * Exported function declarations:
  */
 
-#if defined(_WIN32) || defined(__CYGWIN__) /* WIN */
-/* 0 */
-EXTERN TCHAR *		Tcl_WinUtfToTChar(const char *str, size_t len,
-				Tcl_DString *dsPtr);
-/* 1 */
-EXTERN char *		Tcl_WinTCharToUtf(const TCHAR *str, size_t len,
-				Tcl_DString *dsPtr);
-#endif /* WIN */
 #ifdef MAC_OSX_TCL /* MACOSX */
 /* 0 */
 EXTERN int		Tcl_MacOSXOpenBundleResources(Tcl_Interp *interp,
@@ -75,10 +67,6 @@ typedef struct TclPlatStubs {
     int magic;
     void *hooks;
 
-#if defined(_WIN32) || defined(__CYGWIN__) /* WIN */
-    TCHAR * (*tcl_WinUtfToTChar) (const char *str, size_t len, Tcl_DString *dsPtr); /* 0 */
-    char * (*tcl_WinTCharToUtf) (const TCHAR *str, size_t len, Tcl_DString *dsPtr); /* 1 */
-#endif /* WIN */
 #ifdef MAC_OSX_TCL /* MACOSX */
     int (*tcl_MacOSXOpenBundleResources) (Tcl_Interp *interp, const char *bundleName, int hasResourceFile, size_t maxPathLen, char *libraryPath); /* 0 */
     int (*tcl_MacOSXOpenVersionedBundleResources) (Tcl_Interp *interp, const char *bundleName, const char *bundleVersion, int hasResourceFile, size_t maxPathLen, char *libraryPath); /* 1 */
@@ -97,12 +85,6 @@ extern const TclPlatStubs *tclPlatStubsPtr;
  * Inline function declarations:
  */
 
-#if defined(_WIN32) || defined(__CYGWIN__) /* WIN */
-#define Tcl_WinUtfToTChar \
-	(tclPlatStubsPtr->tcl_WinUtfToTChar) /* 0 */
-#define Tcl_WinTCharToUtf \
-	(tclPlatStubsPtr->tcl_WinTCharToUtf) /* 1 */
-#endif /* WIN */
 #ifdef MAC_OSX_TCL /* MACOSX */
 #define Tcl_MacOSXOpenBundleResources \
 	(tclPlatStubsPtr->tcl_MacOSXOpenBundleResources) /* 0 */
@@ -117,6 +99,16 @@ extern const TclPlatStubs *tclPlatStubsPtr;
 #undef TCL_STORAGE_CLASS
 #define TCL_STORAGE_CLASS DLLIMPORT
 
-#endif /* _TCLPLATDECLS */
-
+#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
+#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
+#endif
 
+#endif /* _TCLPLATDECLS */
diff --git a/generic/tclStubInit.c b/generic/tclStubInit.c
index 493d56f..1320b36 100644
--- a/generic/tclStubInit.c
+++ b/generic/tclStubInit.c
@@ -44,6 +44,9 @@
 #undef TclpGetPid
 #undef TclStaticPackage
 #undef Tcl_BackgroundError
+#undef Tcl_UtfToUniChar
+#undef Tcl_UtfToUniCharDString
+#undef Tcl_UniCharToUtfDString
 #define TclStaticPackage Tcl_StaticPackage
 
 #ifdef TCL_MEM_DEBUG
@@ -104,37 +107,6 @@ TclpGetPid(Tcl_Pid pid)
     return (size_t) pid;
 }
 
-char *
-Tcl_WinUtfToTChar(
-    const char *string,
-    size_t len,
-    Tcl_DString *dsPtr)
-{
-    Tcl_DStringInit(dsPtr);
-    if (!string) {
-	return NULL;
-    }
-    return (char *)TclUtfToWCharDString(string, len, dsPtr);
-}
-
-char *
-Tcl_WinTCharToUtf(
-    const char *string,
-    size_t len,
-    Tcl_DString *dsPtr)
-{
-    Tcl_DStringInit(dsPtr);
-    if (!string) {
-	return NULL;
-    }
-    if (len == TCL_AUTO_LENGTH) {
-	len = wcslen((wchar_t *)string);
-    } else {
-	len /= 2;
-    }
-    return TclWCharToUtfDString((const WCHAR *)string, len, dsPtr);
-}
-
 #if defined(TCL_WIDE_INT_IS_LONG)
 /* On Cygwin64, long is 64-bit while on Win64 long is 32-bit. Therefore
  * we have to make sure that all stub entries on Cygwin64 follow the Win64
@@ -568,10 +540,6 @@ static const TclIntPlatStubs tclIntPlatStubs = {
 static const TclPlatStubs tclPlatStubs = {
     TCL_STUB_MAGIC,
     0,
-#if defined(_WIN32) || defined(__CYGWIN__) /* WIN */
-    Tcl_WinUtfToTChar, /* 0 */
-    Tcl_WinTCharToUtf, /* 1 */
-#endif /* WIN */
 #ifdef MAC_OSX_TCL /* MACOSX */
     Tcl_MacOSXOpenBundleResources, /* 0 */
     Tcl_MacOSXOpenVersionedBundleResources, /* 1 */
@@ -1030,7 +998,7 @@ const TclStubs tclStubs = {
     Tcl_UtfToExternalDString, /* 333 */
     Tcl_UtfToLower, /* 334 */
     Tcl_UtfToTitle, /* 335 */
-    Tcl_UtfToUniChar, /* 336 */
+    Tcl_UtfToChar16, /* 336 */
     Tcl_UtfToUpper, /* 337 */
     Tcl_WriteChars, /* 338 */
     Tcl_WriteObj, /* 339 */
@@ -1048,8 +1016,8 @@ const TclStubs tclStubs = {
     Tcl_UniCharIsWordChar, /* 351 */
     Tcl_UniCharLen, /* 352 */
     Tcl_UniCharNcmp, /* 353 */
-    Tcl_UniCharToUtfDString, /* 354 */
-    Tcl_UtfToUniCharDString, /* 355 */
+    Tcl_Char16ToUtfDString, /* 354 */
+    Tcl_UtfToChar16DString, /* 355 */
     Tcl_GetRegExpFromObj, /* 356 */
     0, /* 357 */
     Tcl_FreeParse, /* 358 */
@@ -1340,6 +1308,9 @@ const TclStubs tclStubs = {
     Tcl_IsShared, /* 643 */
     Tcl_LinkArray, /* 644 */
     Tcl_GetIntForIndex, /* 645 */
+    Tcl_UtfToUniChar, /* 646 */
+    Tcl_UniCharToUtfDString, /* 647 */
+    Tcl_UtfToUniCharDString, /* 648 */
 };
 
 /* !END!: Do not edit above this line. */
diff --git a/generic/tclUtf.c b/generic/tclUtf.c
index b5167a4..644939b 100644
--- a/generic/tclUtf.c
+++ b/generic/tclUtf.c
@@ -221,23 +221,33 @@ three:
  *---------------------------------------------------------------------------
  */
 
+#undef Tcl_UniCharToUtfDString
 char *
 Tcl_UniCharToUtfDString(
-    const Tcl_UniChar *uniStr,	/* Unicode string to convert to UTF-8. */
-    size_t uniLength,		/* Length of Unicode string in Tcl_UniChars
-				 * (must be >= 0). */
+    const int *uniStr,	/* Unicode string to convert to UTF-8. */
+    size_t uniLength,		/* Length of Unicode string. */
     Tcl_DString *dsPtr)		/* UTF-8 representation of string is appended
 				 * to this previously initialized DString. */
 {
-    const Tcl_UniChar *w, *wEnd;
+    const int *w, *wEnd;
     char *p, *string;
     size_t oldLength;
-    int len = 1;
 
     /*
      * UTF-8 string length in bytes will be <= Unicode string length * 4.
      */
 
+    if (uniStr == NULL) {
+	return NULL;
+    }
+    if (uniLength < 0) {
+	uniLength = 0;
+	w = uniStr;
+	while (*w != '\0') {
+	    uniLength++;
+	    w++;
+	}
+    }
     oldLength = Tcl_DStringLength(dsPtr);
     Tcl_DStringSetLength(dsPtr, oldLength + (uniLength + 1) * 4);
     string = Tcl_DStringValue(dsPtr) + oldLength;
@@ -245,46 +255,44 @@ Tcl_UniCharToUtfDString(
     p = string;
     wEnd = uniStr + uniLength;
     for (w = uniStr; w < wEnd; ) {
-	if (!len && ((*w & 0xFC00) != 0xDC00)) {
-	    /* Special case for handling high surrogates. */
-	    p += Tcl_UniCharToUtf(-1, p);
-	}
-	len = Tcl_UniCharToUtf(*w, p);
-	p += len;
-	if ((*w >= 0xD800) && (len < 3)) {
-	    len = 0; /* Indication that high surrogate was found */
-	}
+	p += Tcl_UniCharToUtf(*w, p);
 	w++;
     }
-    if (!len) {
-	/* Special case for handling high surrogates. */
-	p += Tcl_UniCharToUtf(-1, p);
-    }
     Tcl_DStringSetLength(dsPtr, oldLength + (p - string));
 
     return string;
 }
 
-#if (TCL_UTF_MAX > 4) && (defined(__CYGWIN__) || defined(_WIN32))
 char *
-TclWCharToUtfDString(
-    const WCHAR *uniStr,	/* WCHAR string to convert to UTF-8. */
-    size_t uniLength,		/* Length of WCHAR string in Tcl_UniChars
-				 * (must be >= 0). */
+Tcl_Char16ToUtfDString(
+    const unsigned short *uniStr,/* Utf-16 string to convert to UTF-8. */
+    size_t uniLength,		/* Length of Utf-16 string. */
     Tcl_DString *dsPtr)		/* UTF-8 representation of string is appended
 				 * to this previously initialized DString. */
 {
-    const WCHAR *w, *wEnd;
+    const unsigned short *w, *wEnd;
     char *p, *string;
     size_t oldLength;
     int len = 1;
 
     /*
-     * UTF-8 string length in bytes will be <= Unicode string length * 4.
+     * UTF-8 string length in bytes will be <= Utf16 string length * 3.
      */
 
+    if (uniStr == NULL) {
+	return NULL;
+    }
+    if (uniLength < 0) {
+
+	uniLength = 0;
+	w = uniStr;
+	while (*w != '\0') {
+	    uniLength++;
+	    w++;
+	}
+    }
     oldLength = Tcl_DStringLength(dsPtr);
-    Tcl_DStringSetLength(dsPtr, oldLength + (uniLength + 1) * 4);
+    Tcl_DStringSetLength(dsPtr, oldLength + (uniLength + 1) * 3);
     string = Tcl_DStringValue(dsPtr) + oldLength;
 
     p = string;
@@ -309,7 +317,6 @@ TclWCharToUtfDString(
 
     return string;
 }
-#endif
 /*
  *---------------------------------------------------------------------------
  *
@@ -352,13 +359,14 @@ static const unsigned short cp1252[32] = {
    0x2DC, 0x2122, 0x0161, 0x203A, 0x0153,   0x9D, 0x017E, 0x0178
 };
 
+#undef Tcl_UtfToUniChar
 int
 Tcl_UtfToUniChar(
     const char *src,	/* The UTF-8 string. */
-    Tcl_UniChar *chPtr)/* Filled with the Tcl_UniChar represented by
+    int *chPtr)/* Filled with the unsigned int represented by
 				 * the UTF-8 string. */
 {
-    Tcl_UniChar byte;
+    int byte;
 
     /*
      * Unroll 1 to 4 byte UTF-8 sequences.
@@ -374,20 +382,6 @@ Tcl_UtfToUniChar(
 	 * characters representing themselves.
 	 */
 
-#if TCL_UTF_MAX <= 4
-	/* If *chPtr contains a high surrogate (produced by a previous
-	 * Tcl_UtfToUniChar() call) and the next 3 bytes are UTF-8 continuation
-	 * bytes, then we must produce a follow-up low surrogate. We only
-	 * do that if the high surrogate matches the bits we encounter.
-	 */
-	if ((byte >= 0x80)
-		&& (((((byte - 0x10) << 2) & 0xFC) | 0xD800) == (*chPtr & 0xFCFC))
-		&& ((src[1] & 0xF0) == (((*chPtr << 4) & 0x30) | 0x80))
-		&& ((src[2] & 0xC0) == 0x80)) {
-	    *chPtr = ((src[1] & 0x0F) << 6) + (src[2] & 0x3F) + 0xDC00;
-	    return 3;
-	}
-#endif
 	if ((unsigned)(byte-0x80) < (unsigned)0x20) {
 	    *chPtr = cp1252[byte-0x80];
 	} else {
@@ -433,23 +427,11 @@ Tcl_UtfToUniChar(
 	    /*
 	     * Four-byte-character lead byte followed by three trail bytes.
 	     */
-#if TCL_UTF_MAX <= 4
-	    Tcl_UniChar high = (((byte & 0x07) << 8) | ((src[1] & 0x3F) << 2)
-		    | ((src[2] & 0x3F) >> 4)) - 0x40;
-	    if (high >= 0x400) {
-		/* out of range, < 0x10000 or > 0x10ffff */
-	    } else {
-		/* produce high surrogate, advance source pointer */
-		*chPtr = 0xD800 + high;
-		return 1;
-	    }
-#else
 	    *chPtr = (((byte & 0x07) << 18) | ((src[1] & 0x3F) << 12)
 		    | ((src[2] & 0x3F) << 6) | (src[3] & 0x3F));
 	    if ((unsigned)(*chPtr - 0x10000) <= 0xFFFFF) {
 		return 4;
 	    }
-#endif
 	}
 
 	/*
@@ -462,14 +444,13 @@ Tcl_UtfToUniChar(
     return 1;
 }
 
-#if (TCL_UTF_MAX > 4) && (defined(__CYGWIN__) || defined(_WIN32))
 int
-TclUtfToWChar(
+Tcl_UtfToChar16(
     const char *src,	/* The UTF-8 string. */
-    WCHAR *chPtr)/* Filled with the WCHAR represented by
+    unsigned short *chPtr)/* Filled with the unsigned short represented by
 				 * the UTF-8 string. */
 {
-    WCHAR byte;
+    unsigned short byte;
 
     /*
      * Unroll 1 to 4 byte UTF-8 sequences.
@@ -542,7 +523,7 @@ TclUtfToWChar(
 	    /*
 	     * Four-byte-character lead byte followed by three trail bytes.
 	     */
-	    WCHAR high = (((byte & 0x07) << 8) | ((src[1] & 0x3F) << 2)
+	    unsigned short high = (((byte & 0x07) << 8) | ((src[1] & 0x3F) << 2)
 		    | ((src[2] & 0x3F) >> 4)) - 0x40;
 	    if (high >= 0x400) {
 		/* out of range, < 0x10000 or > 0x10ffff */
@@ -562,7 +543,6 @@ TclUtfToWChar(
     *chPtr = byte;
     return 1;
 }
-#endif
 
 /*
  *---------------------------------------------------------------------------
@@ -582,7 +562,8 @@ TclUtfToWChar(
  *---------------------------------------------------------------------------
  */
 
-Tcl_UniChar *
+#undef Tcl_UtfToUniCharDString
+int *
 Tcl_UtfToUniCharDString(
     const char *src,		/* UTF-8 string to convert to Unicode. */
     size_t length,			/* Length of UTF-8 string in bytes, or -1 for
@@ -591,10 +572,13 @@ Tcl_UtfToUniCharDString(
 				 * appended to this previously initialized
 				 * DString. */
 {
-    Tcl_UniChar ch = 0, *w, *wString;
+    int ch = 0, *w, *wString;
     const char *p, *end;
     size_t oldLength;
 
+    if (src == NULL) {
+	return NULL;
+    }
     if (length == TCL_AUTO_LENGTH) {
 	length = strlen(src);
     }
@@ -607,20 +591,20 @@ Tcl_UtfToUniCharDString(
     oldLength = Tcl_DStringLength(dsPtr);
 
     Tcl_DStringSetLength(dsPtr,
-	    oldLength + (int) ((length + 1) * sizeof(Tcl_UniChar)));
-    wString = (Tcl_UniChar *) (Tcl_DStringValue(dsPtr) + oldLength);
+	    oldLength + ((length + 1) * sizeof(int)));
+    wString = (int *) (Tcl_DStringValue(dsPtr) + oldLength);
 
     w = wString;
     p = src;
     end = src + length - 4;
     while (p < end) {
-	p += TclUtfToUniChar(p, &ch);
+	p += Tcl_UtfToUniChar(p, &ch);
 	*w++ = ch;
     }
     end += 4;
     while (p < end) {
 	if (Tcl_UtfCharComplete(p, end-p)) {
-	    p += TclUtfToUniChar(p, &ch);
+	    p += Tcl_UtfToUniChar(p, &ch);
 	} else {
 	    ch = UCHAR(*p++);
 	}
@@ -633,9 +617,8 @@ Tcl_UtfToUniCharDString(
     return wString;
 }
 
-#if (TCL_UTF_MAX > 4) && (defined(__CYGWIN__) || defined(_WIN32))
-WCHAR *
-TclUtfToWCharDString(
+unsigned short *
+Tcl_UtfToChar16DString(
     const char *src,		/* UTF-8 string to convert to Unicode. */
     size_t length,			/* Length of UTF-8 string in bytes, or -1 for
 				 * strlen(). */
@@ -643,10 +626,14 @@ TclUtfToWCharDString(
 				 * appended to this previously initialized
 				 * DString. */
 {
-    WCHAR ch = 0, *w, *wString;
+    unsigned short ch = 0;
+    unsigned short *w, *wString;
     const char *p, *end;
     size_t oldLength;
 
+    if (src == NULL) {
+	return NULL;
+    }
     if (length == TCL_AUTO_LENGTH) {
 	length = strlen(src);
     }
@@ -659,20 +646,20 @@ TclUtfToWCharDString(
     oldLength = Tcl_DStringLength(dsPtr);
 
     Tcl_DStringSetLength(dsPtr,
-	    oldLength + (int) ((length + 1) * sizeof(WCHAR)));
-    wString = (WCHAR *) (Tcl_DStringValue(dsPtr) + oldLength);
+	    oldLength + ((length + 1) * sizeof(unsigned short)));
+    wString = (unsigned short *) (Tcl_DStringValue(dsPtr) + oldLength);
 
     w = wString;
     p = src;
     end = src + length - 4;
     while (p < end) {
-	p += TclUtfToWChar(p, &ch);
+	p += Tcl_UtfToChar16(p, &ch);
 	*w++ = ch;
     }
     end += 4;
     while (p < end) {
 	if (Tcl_UtfCharComplete(p, end-p)) {
-	    p += TclUtfToWChar(p, &ch);
+	    p += Tcl_UtfToChar16(p, &ch);
 	} else {
 	    ch = UCHAR(*p++);
 	}
@@ -684,7 +671,6 @@ TclUtfToWCharDString(
 
     return wString;
 }
-#endif
 /*
  *---------------------------------------------------------------------------
  *
@@ -2161,7 +2147,7 @@ Tcl_UniCharCaseMatch(
 		if ((p != '[') && (p != '?') && (p != '\\')) {
 		    if (nocase) {
 			while (*uniStr && (p != *uniStr)
-				&& (p != (Tcl_UniChar)Tcl_UniCharToLower(*uniStr))) {
+				&& (p != Tcl_UniCharToLower(*uniStr))) {
 			    uniStr++;
 			}
 		    } else {
@@ -2201,13 +2187,13 @@ Tcl_UniCharCaseMatch(
 	    Tcl_UniChar startChar, endChar;
 
 	    uniPattern++;
-	    ch1 = (nocase ? (Tcl_UniChar)Tcl_UniCharToLower(*uniStr) : *uniStr);
+	    ch1 = (nocase ? Tcl_UniCharToLower(*uniStr) : *uniStr);
 	    uniStr++;
 	    while (1) {
 		if ((*uniPattern == ']') || (*uniPattern == 0)) {
 		    return 0;
 		}
-		startChar = (nocase ? (Tcl_UniChar)Tcl_UniCharToLower(*uniPattern)
+		startChar = (nocase ? Tcl_UniCharToLower(*uniPattern)
 			: *uniPattern);
 		uniPattern++;
 		if (*uniPattern == '-') {
@@ -2215,7 +2201,7 @@ Tcl_UniCharCaseMatch(
 		    if (*uniPattern == 0) {
 			return 0;
 		    }
-		    endChar = (nocase ? (Tcl_UniChar)Tcl_UniCharToLower(*uniPattern)
+		    endChar = (nocase ? Tcl_UniCharToLower(*uniPattern)
 			    : *uniPattern);
 		    uniPattern++;
 		    if (((startChar <= ch1) && (ch1 <= endChar))
@@ -2353,7 +2339,7 @@ TclUniCharMatch(
 		if ((p != '[') && (p != '?') && (p != '\\')) {
 		    if (nocase) {
 			while ((string < stringEnd) && (p != *string)
-				&& (p != (Tcl_UniChar)Tcl_UniCharToLower(*string))) {
+				&& (p != Tcl_UniCharToLower(*string))) {
 			    string++;
 			}
 		    } else {
@@ -2394,20 +2380,20 @@ TclUniCharMatch(
 	    Tcl_UniChar ch1, startChar, endChar;
 
 	    pattern++;
-	    ch1 = (nocase ? (Tcl_UniChar)Tcl_UniCharToLower(*string) : *string);
+	    ch1 = (nocase ? Tcl_UniCharToLower(*string) : *string);
 	    string++;
 	    while (1) {
 		if ((*pattern == ']') || (pattern == patternEnd)) {
 		    return 0;
 		}
-		startChar = (nocase ? (Tcl_UniChar)Tcl_UniCharToLower(*pattern) : *pattern);
+		startChar = (nocase ? Tcl_UniCharToLower(*pattern) : *pattern);
 		pattern++;
 		if (*pattern == '-') {
 		    pattern++;
 		    if (pattern == patternEnd) {
 			return 0;
 		    }
-		    endChar = (nocase ? (Tcl_UniChar)Tcl_UniCharToLower(*pattern)
+		    endChar = (nocase ? Tcl_UniCharToLower(*pattern)
 			    : *pattern);
 		    pattern++;
 		    if (((startChar <= ch1) && (ch1 <= endChar))
diff --git a/generic/tclUtil.c b/generic/tclUtil.c
index 2ffd4ea..c9d7003 100644
--- a/generic/tclUtil.c
+++ b/generic/tclUtil.c
@@ -2211,7 +2211,7 @@ Tcl_StringCaseMatch(
 		    if (nocase) {
 			while (*str) {
 			    charLen = TclUtfToUniChar(str, &ch1);
-			    if (ch2==ch1 || ch2==(Tcl_UniChar)Tcl_UniCharToLower(ch1)) {
+			    if (ch2==ch1 || ch2==Tcl_UniCharToLower(ch1)) {
 				break;
 			    }
 			    str += charLen;
diff --git a/generic/tclZipfs.c b/generic/tclZipfs.c
index 914c6bb..4e7cb1f 100644
--- a/generic/tclZipfs.c
+++ b/generic/tclZipfs.c
@@ -4913,7 +4913,8 @@ TclZipfs_AppHook(
 #ifdef _WIN32
 	Tcl_DString ds;
 
-	archive = Tcl_WinTCharToUtf((*argvPtr)[1], -1, &ds);
+	Tcl_DStringInit(&ds);
+	archive = Tcl_WCharToUtfDString((*argvPtr)[1], -1, &ds);
 #else /* !_WIN32 */
 	archive = (*argvPtr)[1];
 #endif /* _WIN32 */
diff --git a/win/tclWin32Dll.c b/win/tclWin32Dll.c
index 4fc97db..a286254 100644
--- a/win/tclWin32Dll.c
+++ b/win/tclWin32Dll.c
@@ -421,84 +421,6 @@ TclWinDriveLetterForVolMountPoint(
 }
 
 /*
- *---------------------------------------------------------------------------
- *
- * Tcl_WinUtfToTChar, Tcl_WinTCharToUtf --
- *
- *	Convert between UTF-8 and Unicode when running Windows.
- *
- *	On Mac and Unix, all strings exchanged between Tcl and the OS are
- *	"char" oriented. We need only one Tcl_Encoding to convert between
- *	UTF-8 and the system's native encoding. We use NULL to represent
- *	that encoding.
- *
- *	On Windows, some strings exchanged between Tcl and the OS are "char"
- *	oriented, while others are in Unicode. We need two Tcl_Encoding APIs
- *	depending on whether we are targeting a "char" or Unicode interface.
- *
- *	Calling Tcl_UtfToExternal() or Tcl_ExternalToUtf() with an encoding
- *	of NULL should always used to convert between UTF-8 and the system's
- *	"char" oriented encoding. The following two functions are used in
- *	Windows-specific code to convert between UTF-8 and Unicode strings.
- *	This saves you the trouble of writing the
- *	following type of fragment over and over:
- *
- *		encoding <- Tcl_GetEncoding("unicode");
- *		nativeBuffer <- UtfToExternal(encoding, utfBuffer);
- *		Tcl_FreeEncoding(encoding);
- *
- *	By convention, in Windows a WCHAR is a Unicode character. If you plan
- *	on targeting a Unicode interface when running on Windows, these
- *	functions should be used. If you plan on targetting a "char" oriented
- *	function on Windows, use Tcl_UtfToExternal() with an encoding of NULL.
- *
- * Results:
- *	The result is a pointer to the string in the desired target encoding.
- *	Storage for the result string is allocated in dsPtr; the caller must
- *	call Tcl_DStringFree() when the result is no longer needed.
- *
- * Side effects:
- *	None.
- *
- *---------------------------------------------------------------------------
- */
-
-WCHAR *
-Tcl_WinUtfToTChar(
-    const char *string,		/* Source string in UTF-8. */
-    size_t len,			/* Source string length in bytes, or -1
-				 * for strlen(). */
-    Tcl_DString *dsPtr)		/* Uninitialized or free DString in which the
-				 * converted string is stored. */
-{
-    Tcl_DStringInit(dsPtr);
-    if (!string) {
-	return NULL;
-    }
-    return TclUtfToWCharDString(string, len, dsPtr);
-}
-
-char *
-Tcl_WinTCharToUtf(
-    const WCHAR *string,	/* Source string in Unicode. */
-    size_t len,			/* Source string length in bytes, or -1
-				 * for platform-specific string length. */
-    Tcl_DString *dsPtr)		/* Uninitialized or free DString in which the
-				 * converted string is stored. */
-{
-    Tcl_DStringInit(dsPtr);
-    if (!string) {
-	return NULL;
-    }
-    if (len == TCL_AUTO_LENGTH) {
-	len = wcslen((WCHAR *)string);
-    } else {
-	len /= 2;
-    }
-    return TclWCharToUtfDString((unsigned short *)string, len, dsPtr);
-}
-
-/*
  *------------------------------------------------------------------------
  *
  * TclWinCPUID --
diff --git a/win/tclWinFCmd.c b/win/tclWinFCmd.c
index 6780328..f080d9f 100644
--- a/win/tclWinFCmd.c
+++ b/win/tclWinFCmd.c
@@ -328,8 +328,10 @@ DoRenameFile(
 	    CharLower(nativeSrcPath);
 	    CharLower(nativeDstPath);
 
-	    src = Tcl_WinTCharToUtf(nativeSrcPath, -1, &srcString);
-	    dst = Tcl_WinTCharToUtf(nativeDstPath, -1, &dstString);
+	    Tcl_DStringInit(&srcString);
+	    Tcl_DStringInit(&dstString);
+	    src = Tcl_WCharToUtfDString(nativeSrcPath, -1, &srcString);
+	    dst = Tcl_WCharToUtfDString(nativeDstPath, -1, &dstString);
 
 	    /*
 	     * Check whether the destination path is actually inside the
@@ -911,8 +913,10 @@ TclpObjCopyDirectory(
 	return TCL_ERROR;
     }
 
-    Tcl_WinUtfToTChar(TclGetString(normSrcPtr), -1, &srcString);
-    Tcl_WinUtfToTChar(TclGetString(normDestPtr), -1, &dstString);
+    Tcl_DStringInit(&srcString);
+    Tcl_DStringInit(&dstString);
+    Tcl_UtfToWCharDString(TclGetString(normSrcPtr), -1, &srcString);
+    Tcl_UtfToWCharDString(TclGetString(normDestPtr), -1, &dstString);
 
     ret = TraverseWinTree(TraversalCopy, &srcString, &dstString, &ds);
 
@@ -984,7 +988,8 @@ TclpObjRemoveDirectory(
 	if (normPtr == NULL) {
 	    return TCL_ERROR;
 	}
-	Tcl_WinUtfToTChar(TclGetString(normPtr), -1, &native);
+	Tcl_DStringInit(&native);
+	Tcl_UtfToWCharDString(TclGetString(normPtr), -1, &native);
 	ret = DoRemoveDirectory(&native, recursive, &ds);
 	Tcl_DStringFree(&native);
     } else {
@@ -1109,7 +1114,10 @@ DoRemoveJustDirectory(
 
   end:
     if (errorPtr != NULL) {
-	char *p = Tcl_WinTCharToUtf(nativePath, -1, errorPtr);
+	char *p;
+
+	Tcl_DStringInit(errorPtr);
+	p = Tcl_WCharToUtfDString(nativePath, -1, errorPtr);
 	for (; *p; ++p) {
 	    if (*p == '\\') *p = '/';
 	}
@@ -1323,7 +1331,8 @@ TraverseWinTree(
     if (nativeErrfile != NULL) {
 	TclWinConvertError(GetLastError());
 	if (errorPtr != NULL) {
-	    Tcl_WinTCharToUtf(nativeErrfile, -1, errorPtr);
+	    Tcl_DStringInit(errorPtr);
+	    Tcl_WCharToUtfDString(nativeErrfile, -1, errorPtr);
 	}
 	result = TCL_ERROR;
     }
@@ -1388,7 +1397,8 @@ TraversalCopy(
      */
 
     if (errorPtr != NULL) {
-	Tcl_WinTCharToUtf(nativeDst, -1, errorPtr);
+	Tcl_DStringInit(errorPtr);
+	Tcl_WCharToUtfDString(nativeDst, -1, errorPtr);
     }
     return TCL_ERROR;
 }
@@ -1443,7 +1453,8 @@ TraversalDelete(
     }
 
     if (errorPtr != NULL) {
-	Tcl_WinTCharToUtf(nativeSrc, -1, errorPtr);
+	Tcl_DStringInit(errorPtr);
+	Tcl_WCharToUtfDString(nativeSrc, -1, errorPtr);
     }
     return TCL_ERROR;
 }
@@ -1651,7 +1662,8 @@ ConvertFileNameFormat(
 	     */
 
 	    tempString = TclGetStringFromObj(tempPath, &length);
-	    nativeName = Tcl_WinUtfToTChar(tempString, length, &ds);
+	    Tcl_DStringInit(&ds);
+	    nativeName = Tcl_UtfToWCharDString(tempString, length, &ds);
 	    Tcl_DecrRefCount(tempPath);
 	    handle = FindFirstFile(nativeName, &data);
 	    if (handle == INVALID_HANDLE_VALUE) {
@@ -1688,7 +1700,7 @@ ConvertFileNameFormat(
 	    }
 
 	    /*
-	     * Purify reports a extraneous UMR in Tcl_WinTCharToUtf() trying
+	     * Purify reports a extraneous UMR in Tcl_WCharToUtfDString() trying
 	     * to dereference nativeName as a Unicode string. I have proven to
 	     * myself that purify is wrong by running the following example
 	     * when nativeName == data.w.cAlternateFileName and noting that
@@ -1700,7 +1712,7 @@ ConvertFileNameFormat(
 	     */
 
 	    Tcl_DStringInit(&dsTemp);
-	    Tcl_WinTCharToUtf(nativeName, -1, &dsTemp);
+	    Tcl_WCharToUtfDString(nativeName, -1, &dsTemp);
 	    Tcl_DStringFree(&ds);
 
 	    /*
@@ -1995,9 +2007,10 @@ TclpCreateTemporaryDirectory(
 	if (dirObj->length < 1) {
 	    goto useSystemTemp;
 	}
-	Tcl_WinUtfToTChar(Tcl_GetString(dirObj), -1, &base);
+	Tcl_DStringInit(&base);
+	Tcl_UtfToWCharDString(Tcl_GetString(dirObj), -1, &base);
 	if (dirObj->bytes[dirObj->length - 1] != '\\') {
-	    TclUtfToWCharDString("\\", -1, &base);
+	    Tcl_UtfToWCharDString("\\", -1, &base);
 	}
     } else {
     useSystemTemp:
@@ -2013,13 +2026,11 @@ TclpCreateTemporaryDirectory(
 #define SUFFIX_LENGTH	8
 
     if (basenameObj) {
-	Tcl_WinUtfToTChar(Tcl_GetString(basenameObj), -1, &name);
-	TclDStringAppendDString(&base, &name);
-	Tcl_DStringFree(&name);
+	Tcl_UtfToWCharDString(Tcl_GetString(basenameObj), -1, &base);
     } else {
-	TclUtfToWCharDString(DEFAULT_TEMP_DIR_PREFIX, -1, &base);
+	Tcl_UtfToWCharDString(DEFAULT_TEMP_DIR_PREFIX, -1, &base);
     }
-    TclUtfToWCharDString("_", -1, &base);
+    Tcl_UtfToWCharDString("_", -1, &base);
 
     /*
      * Now we keep on trying random suffixes until we get one that works
@@ -2046,7 +2057,7 @@ TclpCreateTemporaryDirectory(
 	    tempbuf[i] = randChars[(int) (rand() % numRandChars)];
 	}
 	Tcl_DStringSetLength(&base, baseLen);
-	TclUtfToWCharDString(tempbuf, -1, &base);
+	Tcl_UtfToWCharDString(tempbuf, -1, &base);
     } while (!CreateDirectoryW((LPCWSTR) Tcl_DStringValue(&base), NULL)
 	    && (error = GetLastError()) == ERROR_ALREADY_EXISTS);
 
@@ -2066,7 +2077,8 @@ TclpCreateTemporaryDirectory(
      * as a (clean) Tcl_Obj.
      */
 
-    Tcl_WinTCharToUtf((LPCWSTR) Tcl_DStringValue(&base), -1, &name);
+    Tcl_DStringInit(&name);
+    Tcl_WCharToUtfDString((LPCWSTR) Tcl_DStringValue(&base), -1, &name);
     Tcl_DStringFree(&base);
     return TclDStringToObj(&name);
 }
diff --git a/win/tclWinFile.c b/win/tclWinFile.c
index 14c4378..4073f9a 100644
--- a/win/tclWinFile.c
+++ b/win/tclWinFile.c
@@ -634,10 +634,11 @@ WinReadLinkDirectory(
 	    }
 	}
 
-	Tcl_WinTCharToUtf(
+	Tcl_DStringInit(&ds);
+	Tcl_WCharToUtfDString(
 		reparseBuffer->MountPointReparseBuffer.PathBuffer,
 		reparseBuffer->MountPointReparseBuffer
-		.SubstituteNameLength, &ds);
+		.SubstituteNameLength>>1, &ds);
 
 	copy = Tcl_DStringValue(&ds)+offset;
 	len = Tcl_DStringLength(&ds)-offset;
@@ -1003,7 +1004,8 @@ TclpMatchInDirectory(
 	    dirName = TclDStringAppendLiteral(&dsOrig, "*.*");
 	}
 
-	native = Tcl_WinUtfToTChar(dirName, -1, &ds);
+	Tcl_DStringInit(&ds);
+	native = Tcl_UtfToWCharDString(dirName, -1, &ds);
 	if ((types == NULL) || (types->type != TCL_GLOB_TYPE_DIR)) {
 	    handle = FindFirstFile(native, &data);
 	} else {
@@ -1076,7 +1078,8 @@ TclpMatchInDirectory(
 
 	    native = data.cFileName;
 	    attr = data.dwFileAttributes;
-	    utfname = Tcl_WinTCharToUtf(native, -1, &ds);
+	    Tcl_DStringInit(&ds);
+	    utfname = Tcl_WCharToUtfDString(native, -1, &ds);
 
 	    if (!matchSpecialDots) {
 		/*
@@ -1451,14 +1454,14 @@ TclpGetUserHome(
 	Tcl_DStringFree(&ds);
     } else {
 	Tcl_DStringInit(&ds);
-	wName = TclUtfToWCharDString(domain + 1, -1, &ds);
+	wName = Tcl_UtfToWCharDString(domain + 1, -1, &ds);
 	rc = NetGetDCName(NULL, wName, (LPBYTE *) &wDomain);
 	Tcl_DStringFree(&ds);
 	nameLen = domain - name;
     }
     if (rc == 0) {
 	Tcl_DStringInit(&ds);
-	wName = TclUtfToWCharDString(name, nameLen, &ds);
+	wName = Tcl_UtfToWCharDString(name, nameLen, &ds);
 	while (NetUserGetInfo(wDomain, wName, 1, (LPBYTE *) &uiPtr) != 0) {
 	    /*
 	     * User does not exist; if domain was not specified, try again
@@ -1486,7 +1489,7 @@ TclpGetUserHome(
 	    wHomeDir = uiPtr->usri1_home_dir;
 	    if ((wHomeDir != NULL) && (wHomeDir[0] != '\0')) {
 		size = lstrlenW(wHomeDir);
-		TclWCharToUtfDString(wHomeDir, size, bufferPtr);
+		Tcl_WCharToUtfDString(wHomeDir, size, bufferPtr);
 	    } else {
 		/*
 		 * User exists but has no home dir. Return
@@ -1494,7 +1497,7 @@ TclpGetUserHome(
 		 */
 
 		GetProfilesDirectoryW(buf, &size);
-		TclWCharToUtfDString(buf, size-1, bufferPtr);
+		Tcl_WCharToUtfDString(buf, size-1, bufferPtr);
 		Tcl_DStringAppend(bufferPtr, "/", 1);
 		Tcl_DStringAppend(bufferPtr, name, nameLen);
 	    }
@@ -1864,11 +1867,11 @@ NativeIsExec(
     }
 
     path += len-3;
-    if ((wcsicmp(path, L"exe") == 0)
-	    || (wcsicmp(path, L"com") == 0)
-	    || (wcsicmp(path, L"cmd") == 0)
-	    || (wcsicmp(path, L"cmd") == 0)
-	    || (wcsicmp(path, L"bat") == 0)) {
+    if ((_wcsicmp(path, L"exe") == 0)
+	    || (_wcsicmp(path, L"com") == 0)
+	    || (_wcsicmp(path, L"cmd") == 0)
+	    || (_wcsicmp(path, L"cmd") == 0)
+	    || (_wcsicmp(path, L"bat") == 0)) {
 	return 1;
     }
     return 0;
@@ -1962,7 +1965,8 @@ TclpGetCwd(
 	    && (native[2] == '\\') && (native[3] == '\\')) {
 	native += 2;
     }
-    Tcl_WinTCharToUtf(native, -1, bufferPtr);
+    Tcl_DStringInit(bufferPtr);
+    Tcl_WCharToUtfDString(native, -1, bufferPtr);
 
     /*
      * Convert to forward slashes for easier use in scripts.
@@ -2170,7 +2174,8 @@ NativeDev(
     const char *fullPath;
 
     GetFullPathName(nativePath, MAX_PATH, nativeFullPath, &nativePart);
-    fullPath = Tcl_WinTCharToUtf(nativeFullPath, -1, &ds);
+    Tcl_DStringInit(&ds);
+    fullPath = Tcl_WCharToUtfDString(nativeFullPath, -1, &ds);
 
     if ((fullPath[0] == '\\') && (fullPath[1] == '\\')) {
 	const char *p;
@@ -2191,7 +2196,8 @@ NativeDev(
 	} else {
 	    p++;
 	}
-	nativeVol = Tcl_WinUtfToTChar(fullPath, p - fullPath, &volString);
+	Tcl_DStringInit(&volString);
+	nativeVol = Tcl_UtfToWCharDString(fullPath, p - fullPath, &volString);
 	dw = (DWORD) -1;
 	GetVolumeInformation(nativeVol, NULL, 0, &dw, NULL, NULL, NULL, 0);
 
@@ -2471,7 +2477,8 @@ TclpFilesystemPathType(
     } else {
 	Tcl_DString ds;
 
-	Tcl_WinTCharToUtf(volType, -1, &ds);
+	Tcl_DStringInit(&ds);
+	Tcl_WCharToUtfDString(volType, -1, &ds);
 	return TclDStringToObj(&ds);
     }
 #undef VOL_BUF_SIZE
@@ -2541,7 +2548,10 @@ TclpObjNormalizePath(
 	     */
 
 	    WIN32_FILE_ATTRIBUTE_DATA data;
-	    const WCHAR *nativePath = Tcl_WinUtfToTChar(path,
+	    const WCHAR *nativePath;
+
+	    Tcl_DStringInit(&ds);
+	    nativePath = Tcl_UtfToWCharDString(path,
 		    currentPathEndPosition - path, &ds);
 
 	    if (GetFileAttributesEx(nativePath,
@@ -2743,11 +2753,14 @@ TclpObjNormalizePath(
 
 	if (1) {
 	    WCHAR wpath[MAX_PATH];
-	    const WCHAR *nativePath =
-		    Tcl_WinUtfToTChar(path, lastValidPathEnd - path, &ds);
-	    DWORD wpathlen = GetLongPathNameProc(nativePath,
-		    (WCHAR *) wpath, MAX_PATH);
+	    const WCHAR *nativePath;
+	    DWORD wpathlen;
 
+	    Tcl_DStringInit(&ds);
+	    nativePath =
+		    Tcl_UtfToWCharDString(path, lastValidPathEnd - path, &ds);
+	    wpathlen = GetLongPathNameProc(nativePath,
+		    (WCHAR *) wpath, MAX_PATH);
 	    /*
 	     * We have to make the drive letter uppercase.
 	     */
@@ -2774,8 +2787,9 @@ TclpObjNormalizePath(
 	 * native encoding, so we have to convert it to Utf.
 	 */
 
-	Tcl_WinTCharToUtf((const WCHAR *) Tcl_DStringValue(&dsNorm),
-		Tcl_DStringLength(&dsNorm), &ds);
+	Tcl_DStringInit(&ds);
+	Tcl_WCharToUtfDString((const WCHAR *) Tcl_DStringValue(&dsNorm),
+		Tcl_DStringLength(&dsNorm)>>1, &ds);
 	nextCheckpoint = Tcl_DStringLength(&ds);
 	if (*lastValidPathEnd != 0) {
 	    /*
@@ -2950,7 +2964,8 @@ TclpNativeToNormalized(
     size_t len;
     char *copy, *p;
 
-    Tcl_WinTCharToUtf((const WCHAR *) clientData, -1, &ds);
+    Tcl_DStringInit(&ds);
+    Tcl_WCharToUtfDString((const WCHAR *) clientData, -1, &ds);
     copy = Tcl_DStringValue(&ds);
     len = Tcl_DStringLength(&ds);
 
diff --git a/win/tclWinInit.c b/win/tclWinInit.c
index 1bd1548..c6d5c1d 100644
--- a/win/tclWinInit.c
+++ b/win/tclWinInit.c
@@ -476,8 +476,8 @@ TclpGetUserName(
 	    return NULL;
 	}
 	cchUserNameLen--;
-	cchUserNameLen *= sizeof(WCHAR);
-	Tcl_WinTCharToUtf(szUserName, cchUserNameLen, bufferPtr);
+	Tcl_DStringInit(bufferPtr);
+	Tcl_WCharToUtfDString(szUserName, cchUserNameLen, bufferPtr);
     }
     return Tcl_DStringValue(bufferPtr);
 }
diff --git a/win/tclWinLoad.c b/win/tclWinLoad.c
index be6299c..254f59a 100644
--- a/win/tclWinLoad.c
+++ b/win/tclWinLoad.c
@@ -95,7 +95,8 @@ TclpDlopen(
         firstError = (nativeName == NULL) ?
 		ERROR_MOD_NOT_FOUND : GetLastError();
 
-	nativeName = Tcl_WinUtfToTChar(TclGetString(pathPtr), -1, &ds);
+	Tcl_DStringInit(&ds);
+	nativeName = Tcl_UtfToWCharDString(TclGetString(pathPtr), -1, &ds);
 	hInstance = LoadLibraryEx(nativeName, NULL,
 		LOAD_WITH_ALTERED_SEARCH_PATH);
 	Tcl_DStringFree(&ds);
diff --git a/win/tclWinPipe.c b/win/tclWinPipe.c
index 1aa28bc..fae5ed3 100644
--- a/win/tclWinPipe.c
+++ b/win/tclWinPipe.c
@@ -577,7 +577,8 @@ TclpOpenFile(
 	break;
     }
 
-    nativePath = Tcl_WinUtfToTChar(path, -1, &ds);
+    Tcl_DStringInit(&ds);
+    nativePath = Tcl_UtfToWCharDString(path, -1, &ds);
 
     /*
      * If the file is not being created, use the existing file attributes.
@@ -1290,7 +1291,8 @@ ApplicationType(
     for (i = 0; i < (int) (sizeof(extensions) / sizeof(extensions[0])); i++) {
 	Tcl_DStringSetLength(&nameBuf, nameLen);
 	Tcl_DStringAppend(&nameBuf, extensions[i], -1);
-	nativeName = Tcl_WinUtfToTChar(Tcl_DStringValue(&nameBuf),
+	Tcl_DStringInit(&ds);
+	nativeName = Tcl_UtfToWCharDString(Tcl_DStringValue(&nameBuf),
 		Tcl_DStringLength(&nameBuf), &ds);
 	found = SearchPath(NULL, nativeName, NULL, MAX_PATH,
 		nativeFullPath, &rest);
@@ -1308,7 +1310,8 @@ ApplicationType(
 	if ((attr == 0xffffffff) || (attr & FILE_ATTRIBUTE_DIRECTORY)) {
 	    continue;
 	}
-	strcpy(fullName, Tcl_WinTCharToUtf(nativeFullPath, -1, &ds));
+	Tcl_DStringInit(&ds);
+	strcpy(fullName, Tcl_WCharToUtfDString(nativeFullPath, -1, &ds));
 	Tcl_DStringFree(&ds);
 
 	ext = strrchr(fullName, '.');
@@ -1399,7 +1402,8 @@ ApplicationType(
 	 */
 
 	GetShortPathName(nativeFullPath, nativeFullPath, MAX_PATH);
-	strcpy(fullName, Tcl_WinTCharToUtf(nativeFullPath, -1, &ds));
+	Tcl_DStringInit(&ds);
+	strcpy(fullName, Tcl_WCharToUtfDString(nativeFullPath, -1, &ds));
 	Tcl_DStringFree(&ds);
     }
     return applType;
@@ -1727,7 +1731,8 @@ BuildCommandLine(
 	}
     }
     Tcl_DStringFree(linePtr);
-    Tcl_WinUtfToTChar(Tcl_DStringValue(&ds), Tcl_DStringLength(&ds), linePtr);
+    Tcl_DStringInit(linePtr);
+    Tcl_UtfToWCharDString(Tcl_DStringValue(&ds), Tcl_DStringLength(&ds), linePtr);
     Tcl_DStringFree(&ds);
 }
 
@@ -3210,7 +3215,8 @@ TclpOpenTemporaryFile(
     if (basenameObj) {
 	const char *string = TclGetStringFromObj(basenameObj, &length);
 
-	Tcl_WinUtfToTChar(string, length, &buf);
+	Tcl_DStringInit(&buf);
+	Tcl_UtfToWCharDString(string, length, &buf);
 	memcpy(namePtr, Tcl_DStringValue(&buf), Tcl_DStringLength(&buf));
 	namePtr += Tcl_DStringLength(&buf);
 	Tcl_DStringFree(&buf);
@@ -3230,7 +3236,8 @@ TclpOpenTemporaryFile(
 
 	sprintf(number, "%d.TMP", counter);
 	counter = (unsigned short) (counter + 1);
-	Tcl_WinUtfToTChar(number, strlen(number), &buf);
+	Tcl_DStringInit(&buf);
+	Tcl_UtfToWCharDString(number, strlen(number), &buf);
 	Tcl_DStringSetLength(&buf, Tcl_DStringLength(&buf) + 1);
 	memcpy(namePtr, Tcl_DStringValue(&buf), Tcl_DStringLength(&buf) + 1);
 	Tcl_DStringFree(&buf);
diff --git a/win/tclWinSerial.c b/win/tclWinSerial.c
index 9f559e6..fed1c5e 100644
--- a/win/tclWinSerial.c
+++ b/win/tclWinSerial.c
@@ -1669,7 +1669,8 @@ SerialSetOptionProc(
 	if (!GetCommState(infoPtr->handle, &dcb)) {
 	    goto getStateFailed;
 	}
-	native = Tcl_WinUtfToTChar(value, -1, &ds);
+	Tcl_DStringInit(&ds);
+	native = Tcl_UtfToWCharDString(value, -1, &ds);
 	result = BuildCommDCB(native, &dcb);
 	Tcl_DStringFree(&ds);
 
diff --git a/win/tclWinSock.c b/win/tclWinSock.c
index 5cb19e9..1679bbe 100644
--- a/win/tclWinSock.c
+++ b/win/tclWinSock.c
@@ -367,15 +367,15 @@ InitializeHostName(
     DWORD length = MAX_COMPUTERNAME_LENGTH + 1;
     Tcl_DString ds;
 
+    Tcl_DStringInit(&ds);
     if (GetComputerName(tbuf, &length) != 0) {
 	/*
 	 * Convert string from native to UTF then change to lowercase.
 	 */
 
-	Tcl_UtfToLower(Tcl_WinTCharToUtf(tbuf, -1, &ds));
+	Tcl_UtfToLower(Tcl_WCharToUtfDString(tbuf, -1, &ds));
 
     } else {
-	Tcl_DStringInit(&ds);
 	if (TclpHasSockets(NULL) == TCL_OK) {
 	    /*
 	     * The buffer size of 256 is recommended by the MSDN page that