merge trunk

32 files changed, 333 insertions, 251 deletions

diff --git a/generic/tclAssembly.c b/generic/tclAssembly.c
index 02144a1..83f4fe9 100644
--- a/generic/tclAssembly.c
+++ b/generic/tclAssembly.c
@@ -265,7 +265,7 @@ static int		CheckStrictlyPositive(Tcl_Interp*, int);
 static ByteCode *	CompileAssembleObj(Tcl_Interp *interp,
 			    Tcl_Obj *objPtr);
 static void		CompileEmbeddedScript(AssemblyEnv*, Tcl_Token*,
-			    TalInstDesc*);
+			    const TalInstDesc*);
 static int		DefineLabel(AssemblyEnv* envPtr, const char* label);
 static void		DeleteMirrorJumpTable(JumptableInfo* jtPtr);
 static void		DupAssembleCodeInternalRep(Tcl_Obj* src,
@@ -350,7 +350,7 @@ static const Tcl_ObjType assembleCodeType = {
  * Source instructions recognized in the Tcl Assembly Language (TAL)
  */
 
-TalInstDesc TalInstructionTable[] = {
+static const TalInstDesc TalInstructionTable[] = {
     /* PUSH must be first, see the code near the end of TclAssembleCode */
     {"push",		ASSEM_PUSH,	(INST_PUSH1<<8
 					 | INST_PUSH4),		0,	1},
@@ -1768,7 +1768,7 @@ static void
 CompileEmbeddedScript(
     AssemblyEnv* assemEnvPtr,	/* Assembly environment */
     Tcl_Token* tokenPtr,	/* Tcl_Token containing the script */
-    TalInstDesc* instPtr)	/* Instruction that determines whether
+    const TalInstDesc* instPtr)	/* Instruction that determines whether
 				 * the script is 'expr' or 'eval' */
 {
     CompileEnv* envPtr = assemEnvPtr->envPtr;
diff --git a/generic/tclBasic.c b/generic/tclBasic.c
index 0b02d0d..537750e 100644
--- a/generic/tclBasic.c
+++ b/generic/tclBasic.c
@@ -134,6 +134,8 @@ static void		MathFuncWrongNumArgs(Tcl_Interp *interp, int expected,
 static Tcl_NRPostProc	NRCoroutineActivateCallback;
 static Tcl_NRPostProc	NRCoroutineCallerCallback;
 static Tcl_NRPostProc	NRCoroutineExitCallback;
+static int NRCommand(ClientData data[], Tcl_Interp *interp, int result);
+
 static Tcl_NRPostProc	NRRunObjProc;
 static Tcl_NRPostProc	NRTailcallEval;
 static Tcl_ObjCmdProc	OldMathFuncProc;
@@ -2610,7 +2612,7 @@ TclRenameCommand(
     Tcl_DStringInit(&newFullName);
     Tcl_DStringAppend(&newFullName, newNsPtr->fullName, -1);
     if (newNsPtr != iPtr->globalNsPtr) {
-	Tcl_DStringAppend(&newFullName, "::", 2);
+	TclDStringAppendLiteral(&newFullName, "::");
     }
     Tcl_DStringAppend(&newFullName, newTail, -1);
     cmdPtr->refCount++;
@@ -3468,7 +3470,7 @@ Tcl_CreateMathFunc(
     data->clientData = clientData;
 
     Tcl_DStringInit(&bigName);
-    Tcl_DStringAppend(&bigName, "::tcl::mathfunc::", -1);
+    TclDStringAppendLiteral(&bigName, "::tcl::mathfunc::");
     Tcl_DStringAppend(&bigName, name, -1);
 
     Tcl_CreateObjCommand(interp, Tcl_DStringValue(&bigName),
@@ -4363,7 +4365,7 @@ TclNRRunCallbacks(
     return result;
 }
 
-int
+static int
 NRCommand(
     ClientData data[],
     Tcl_Interp *interp,
@@ -8593,7 +8595,7 @@ RewindCoroutine(
     corPtr->eePtr->rewind = 1;
     TclNRAddCallback(interp, RewindCoroutineCallback, state,
 	    NULL, NULL, NULL);
-    return NRInterpCoroutine(corPtr, interp, 0, NULL);
+    return TclNRInterpCoroutine(corPtr, interp, 0, NULL);
 }
 
 static void
@@ -8820,7 +8822,7 @@ NRCoroInjectObjCmd(
     }
 
     cmdPtr = (Command *) Tcl_GetCommandFromObj(interp, objv[1]);
-    if ((!cmdPtr) || (cmdPtr->nreProc != NRInterpCoroutine)) {
+    if ((!cmdPtr) || (cmdPtr->nreProc != TclNRInterpCoroutine)) {
         Tcl_AppendResult(interp, "can only inject a command into a coroutine",
                 NULL);
         Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "COROUTINE",
@@ -8849,7 +8851,7 @@ NRCoroInjectObjCmd(
 }
 
 int
-NRInterpCoroutine(
+TclNRInterpCoroutine(
     ClientData clientData,
     Tcl_Interp *interp,		/* Current interpreter. */
     int objc,			/* Number of arguments. */
@@ -8971,12 +8973,12 @@ TclNRCoroutineObjCmd(
     Tcl_DStringInit(&ds);
     if (nsPtr != iPtr->globalNsPtr) {
 	Tcl_DStringAppend(&ds, nsPtr->fullName, -1);
-	Tcl_DStringAppend(&ds, "::", 2);
+	TclDStringAppendLiteral(&ds, "::");
     }
     Tcl_DStringAppend(&ds, procName, -1);
 
     cmdPtr = (Command *) Tcl_NRCreateCommand(interp, Tcl_DStringValue(&ds),
-	    /*objProc*/ NULL, NRInterpCoroutine, corPtr, DeleteCoroutine);
+	    /*objProc*/ NULL, TclNRInterpCoroutine, corPtr, DeleteCoroutine);
     Tcl_DStringFree(&ds);
 
     corPtr->cmdPtr = cmdPtr;
diff --git a/generic/tclCmdAH.c b/generic/tclCmdAH.c
index 4292224..f09ee70 100644
--- a/generic/tclCmdAH.c
+++ b/generic/tclCmdAH.c
@@ -629,24 +629,26 @@ EncodingDirsObjCmd(
     int objc,			/* Number of arguments. */
     Tcl_Obj *const objv[])	/* Argument objects. */
 {
+    Tcl_Obj *dirListObj;
+
     if (objc > 3) {
-	Tcl_WrongNumArgs(interp, 1, objv, "?dirList?");
+	Tcl_WrongNumArgs(interp, 2, objv, "?dirList?");
 	return TCL_ERROR;
     }
-    objc -= 1;
-    objv += 1;
-    if (objc == 1) {
+    if (objc == 2) {
 	Tcl_SetObjResult(interp, Tcl_GetEncodingSearchPath());
 	return TCL_OK;
     }
-    if (Tcl_SetEncodingSearchPath(objv[1]) == TCL_ERROR) {
+
+    dirListObj = objv[2];
+    if (Tcl_SetEncodingSearchPath(dirListObj) == TCL_ERROR) {
 	Tcl_AppendResult(interp, "expected directory list but got \"",
-		TclGetString(objv[1]), "\"", NULL);
+		TclGetString(dirListObj), "\"", NULL);
 	Tcl_SetErrorCode(interp, "TCL", "OPERATION", "ENCODING", "BADPATH",
 		NULL);
 	return TCL_ERROR;
     }
-    Tcl_SetObjResult(interp, objv[1]);
+    Tcl_SetObjResult(interp, dirListObj);
     return TCL_OK;
 }
 
@@ -1043,9 +1045,9 @@ TclMakeFileCommandSafe(
     Tcl_DString oldBuf, newBuf;
 
     Tcl_DStringInit(&oldBuf);
-    Tcl_DStringAppend(&oldBuf, "::tcl::file::", -1);
+    TclDStringAppendLiteral(&oldBuf, "::tcl::file::");
     Tcl_DStringInit(&newBuf);
-    Tcl_DStringAppend(&newBuf, "tcl:file:", -1);
+    TclDStringAppendLiteral(&newBuf, "tcl:file:");
     for (i=0 ; unsafeInfo[i].cmdName != NULL ; i++) {
 	if (unsafeInfo[i].unsafe) {
 	    const char *oldName, *newName;
diff --git a/generic/tclCompCmds.c b/generic/tclCompCmds.c
index 5b7e0a5..3540716 100644
--- a/generic/tclCompCmds.c
+++ b/generic/tclCompCmds.c
@@ -820,7 +820,7 @@ TclCompileDictForCmd(
      */
 
     Tcl_DStringInit(&buffer);
-    Tcl_DStringAppend(&buffer, varsTokenPtr[1].start, varsTokenPtr[1].size);
+    TclDStringAppendToken(&buffer, &varsTokenPtr[1]);
     if (Tcl_SplitList(NULL, Tcl_DStringValue(&buffer), &numVars,
 	    &argv) != TCL_OK) {
 	Tcl_DStringFree(&buffer);
@@ -1961,7 +1961,7 @@ TclCompileForeachCmd(
 	 */
 
 	Tcl_DStringInit(&varList);
-	Tcl_DStringAppend(&varList, tokenPtr[1].start, tokenPtr[1].size);
+	TclDStringAppendToken(&varList, &tokenPtr[1]);
 	code = Tcl_SplitList(interp, Tcl_DStringValue(&varList),
 		&varcList[loopIndex], &varvList[loopIndex]);
 	Tcl_DStringFree(&varList);
diff --git a/generic/tclCompCmdsSZ.c b/generic/tclCompCmdsSZ.c
index b950e21..8ed3a95 100644
--- a/generic/tclCompCmdsSZ.c
+++ b/generic/tclCompCmdsSZ.c
@@ -1558,8 +1558,7 @@ IssueSwitchJumpTable(
 	     */
 
 	    Tcl_DStringInit(&buffer);
-	    Tcl_DStringAppend(&buffer, bodyToken[i]->start,
-		    bodyToken[i]->size);
+	    TclDStringAppendToken(&buffer, bodyToken[i]);
 	    hPtr = Tcl_CreateHashEntry(&jtPtr->hashTable,
 		    Tcl_DStringValue(&buffer), &isNew);
 	    if (isNew) {
diff --git a/generic/tclCompExpr.c b/generic/tclCompExpr.c
index 4212b6d..890d518 100644
--- a/generic/tclCompExpr.c
+++ b/generic/tclCompExpr.c
@@ -2296,7 +2296,7 @@ CompileExprTree(
 		int length;
 
 		Tcl_DStringInit(&cmdName);
-		Tcl_DStringAppend(&cmdName, "tcl::mathfunc::", -1);
+		TclDStringAppendLiteral(&cmdName, "tcl::mathfunc::");
 		p = TclGetStringFromObj(*funcObjv, &length);
 		funcObjv++;
 		Tcl_DStringAppend(&cmdName, p, length);
diff --git a/generic/tclCompile.c b/generic/tclCompile.c
index 1d88e11..d4ca284 100644
--- a/generic/tclCompile.c
+++ b/generic/tclCompile.c
@@ -1661,8 +1661,8 @@ TclCompileScript(
 		     * have side effects that rely on the unmodified string.
 		     */
 
-		    Tcl_DStringSetLength(&ds, 0);
-		    Tcl_DStringAppend(&ds, tokenPtr[1].start,tokenPtr[1].size);
+		    TclDStringClear(&ds);
+		    TclDStringAppendToken(&ds, &tokenPtr[1]);
 
 		    cmdPtr = (Command *) Tcl_FindCommand(interp,
 			    Tcl_DStringValue(&ds),
@@ -2044,7 +2044,7 @@ TclCompileTokens(
     for ( ;  count > 0;  count--, tokenPtr++) {
 	switch (tokenPtr->type) {
 	case TCL_TOKEN_TEXT:
-	    Tcl_DStringAppend(&textBuffer, tokenPtr->start, tokenPtr->size);
+	    TclDStringAppendToken(&textBuffer, tokenPtr);
 	    TclAdvanceLines(&envPtr->line, tokenPtr->start,
 		    tokenPtr->start + tokenPtr->size);
 	    break;
@@ -2091,9 +2091,7 @@ TclCompileTokens(
 	     */
 
 	    if (Tcl_DStringLength(&textBuffer) > 0) {
-		int literal = TclRegisterNewLiteral(envPtr,
-			Tcl_DStringValue(&textBuffer),
-			Tcl_DStringLength(&textBuffer));
+		int literal = TclRegisterDStringLiteral(envPtr, &textBuffer);
 
 		TclEmitPush(literal, envPtr);
 		numObjsToConcat++;
@@ -2120,9 +2118,7 @@ TclCompileTokens(
 	    if (Tcl_DStringLength(&textBuffer) > 0) {
 		int literal;
 
-		literal = TclRegisterNewLiteral(envPtr,
-			Tcl_DStringValue(&textBuffer),
-			Tcl_DStringLength(&textBuffer));
+		literal = TclRegisterDStringLiteral(envPtr, &textBuffer);
 		TclEmitPush(literal, envPtr);
 		numObjsToConcat++;
 		Tcl_DStringFree(&textBuffer);
@@ -2145,13 +2141,10 @@ TclCompileTokens(
      */
 
     if (Tcl_DStringLength(&textBuffer) > 0) {
-	int literal;
+	int literal = TclRegisterDStringLiteral(envPtr, &textBuffer);
 
-	literal = TclRegisterNewLiteral(envPtr, Tcl_DStringValue(&textBuffer),
-		Tcl_DStringLength(&textBuffer));
 	TclEmitPush(literal, envPtr);
 	numObjsToConcat++;
-
 	if (numCL) {
 	    TclContinuationsEnter(envPtr->literalArrayPtr[literal].objPtr,
 		    numCL, clPosition);
diff --git a/generic/tclCompile.h b/generic/tclCompile.h
index 58663fd..ba78c36 100644
--- a/generic/tclCompile.h
+++ b/generic/tclCompile.h
@@ -866,8 +866,7 @@ typedef struct {
  *----------------------------------------------------------------
  */
 
-MODULE_SCOPE Tcl_NRPostProc	NRCommand;
-MODULE_SCOPE Tcl_ObjCmdProc	NRInterpCoroutine;
+MODULE_SCOPE Tcl_ObjCmdProc	TclNRInterpCoroutine;
 
 /*
  *----------------------------------------------------------------
@@ -1365,6 +1364,16 @@ MODULE_SCOPE Tcl_Obj	*TclNewInstNameObj(unsigned char inst);
     (envPtr->procPtr || envPtr->iPtr->varFramePtr->localCachePtr)
 
 /*
+ * Macros for making it easier to deal with tokens and DStrings.
+ */
+
+#define TclDStringAppendToken(dsPtr, tokenPtr) \
+    Tcl_DStringAppend((dsPtr), (tokenPtr)->start, (tokenPtr)->size)
+#define TclRegisterDStringLiteral(envPtr, dsPtr) \
+    TclRegisterLiteral(envPtr, Tcl_DStringValue(dsPtr), \
+	    Tcl_DStringLength(dsPtr), /*flags*/ 0)
+
+/*
  * DTrace probe macros (NOPs if DTrace support is not enabled).
  */
 
diff --git a/generic/tclConfig.c b/generic/tclConfig.c
index b4735e8..dea487a 100644
--- a/generic/tclConfig.c
+++ b/generic/tclConfig.c
@@ -155,7 +155,7 @@ Tcl_RegisterConfig(
      */
 
     Tcl_DStringInit(&cmdName);
-    Tcl_DStringAppend(&cmdName, "::", -1);
+    TclDStringAppendLiteral(&cmdName, "::");
     Tcl_DStringAppend(&cmdName, pkgName, -1);
 
     /*
@@ -173,7 +173,7 @@ Tcl_RegisterConfig(
 	}
     }
 
-    Tcl_DStringAppend(&cmdName, "::pkgconfig", -1);
+    TclDStringAppendLiteral(&cmdName, "::pkgconfig");
 
     if (Tcl_CreateObjCommand(interp, Tcl_DStringValue(&cmdName),
 	    QueryConfigObjCmd, cdPtr, QueryConfigDelete) == NULL) {
diff --git a/generic/tclEncoding.c b/generic/tclEncoding.c
index 49418c9..0fa6661 100644
--- a/generic/tclEncoding.c
+++ b/generic/tclEncoding.c
@@ -1872,9 +1872,9 @@ LoadTableEncoding(
      * Read lines from the encoding until EOF.
      */
 
-    for (Tcl_DStringSetLength(&lineString, 0);
+    for (TclDStringClear(&lineString);
 	    (len = Tcl_Gets(chan, &lineString)) >= 0;
-	    Tcl_DStringSetLength(&lineString, 0)) {
+	    TclDStringClear(&lineString)) {
 	const unsigned char *p;
 	int to, from;
 
diff --git a/generic/tclEnsemble.c b/generic/tclEnsemble.c
index 1e1a901..754e480 100644
--- a/generic/tclEnsemble.c
+++ b/generic/tclEnsemble.c
@@ -1425,9 +1425,9 @@ TclMakeEnsemble(
 
     Tcl_DStringInit(&buf);
     Tcl_DStringInit(&hiddenBuf);
-    Tcl_DStringAppend(&hiddenBuf, "tcl:", -1);
+    TclDStringAppendLiteral(&hiddenBuf, "tcl:");
     Tcl_DStringAppend(&hiddenBuf, name, -1);
-    Tcl_DStringAppend(&hiddenBuf, ":", -1);
+    TclDStringAppendLiteral(&hiddenBuf, ":");
     hiddenLen = Tcl_DStringLength(&hiddenBuf);
     if (name[0] == ':' && name[1] == ':') {
 	/*
@@ -1443,14 +1443,14 @@ TclMakeEnsemble(
 	 * multi-word list differently to a single word.
 	 */
 
-	Tcl_DStringAppend(&buf, "::tcl", -1);
+	TclDStringAppendLiteral(&buf, "::tcl");
 
 	if (Tcl_SplitList(NULL, name, &nameCount, &nameParts) != TCL_OK) {
 	    Tcl_Panic("invalid ensemble name '%s'", name);
 	}
 
 	for (i = 0; i < nameCount; ++i) {
-	    Tcl_DStringAppend(&buf, "::", 2);
+	    TclDStringAppendLiteral(&buf, "::");
 	    Tcl_DStringAppend(&buf, nameParts[i], -1);
 	}
     }
@@ -1485,7 +1485,7 @@ TclMakeEnsemble(
 	Tcl_Obj *mapDict, *fromObj, *toObj;
 	Command *cmdPtr;
 
-	Tcl_DStringAppend(&buf, "::", 2);
+	TclDStringAppendLiteral(&buf, "::");
 	TclNewObj(mapDict);
 	for (i=0 ; map[i].name != NULL ; i++) {
 	    fromObj = Tcl_NewStringObj(map[i].name, -1);
@@ -1615,10 +1615,10 @@ NsEnsembleImplementationCmdNR(
 	    Tcl_Panic("List of ensemble parameters is not a list");
 	}
 	for (; len>0; len--,elemPtrs++) {
-	    Tcl_DStringAppend(&buf, Tcl_GetString(*elemPtrs), -1);
-	    Tcl_DStringAppend(&buf, " ", -1);
+	    TclDStringAppendObj(&buf, *elemPtrs);
+	    TclDStringAppendLiteral(&buf, " ");
 	}
-	Tcl_DStringAppend(&buf, "subcommand ?arg ...?", -1);
+	TclDStringAppendLiteral(&buf, "subcommand ?arg ...?");
 	Tcl_WrongNumArgs(interp, 1, objv, Tcl_DStringValue(&buf));
 	Tcl_DStringFree(&buf);
 
diff --git a/generic/tclEnv.c b/generic/tclEnv.c
index e45ae6a..b5ae6ea 100644
--- a/generic/tclEnv.c
+++ b/generic/tclEnv.c
@@ -772,9 +772,9 @@ TclCygwinPutenv(
 	} else {
 	    int size;
 
-	    size = cygwin_posix_to_win32_path_list_buf_size(value);
+	    size = cygwin_conv_path_list(0, value, NULL, 0);
 	    buf = alloca(size + 1);
-	    cygwin_posix_to_win32_path_list(value, buf);
+	    cygwin_conv_path_list(0, value, buf, size);
 	}
 
 	SetEnvironmentVariableA(name, buf);
diff --git a/generic/tclFileName.c b/generic/tclFileName.c
index 48c5454..edb6581 100644
--- a/generic/tclFileName.c
+++ b/generic/tclFileName.c
@@ -72,9 +72,9 @@ SetResultLength(
 {
     Tcl_DStringSetLength(resultPtr, offset);
     if (extended == 2) {
-	Tcl_DStringAppend(resultPtr, "//?/UNC/", 8);
+	TclDStringAppendLiteral(resultPtr, "//?/UNC/");
     } else if (extended == 1) {
-	Tcl_DStringAppend(resultPtr, "//?/", 4);
+	TclDStringAppendLiteral(resultPtr, "//?/");
     }
 }
 
@@ -131,7 +131,7 @@ ExtractWinRoot(
 	if (path[1] != '/' && path[1] != '\\') {
 	    SetResultLength(resultPtr, offset, extended);
 	    *typePtr = TCL_PATH_VOLUME_RELATIVE;
-	    Tcl_DStringAppend(resultPtr, "/", 1);
+	    TclDStringAppendLiteral(resultPtr, "/");
 	    return &path[1];
 	}
 	host = &path[2];
@@ -161,7 +161,7 @@ ExtractWinRoot(
 	     */
 
 	    *typePtr = TCL_PATH_VOLUME_RELATIVE;
-	    Tcl_DStringAppend(resultPtr, "/", 1);
+	    TclDStringAppendLiteral(resultPtr, "/");
 	    return &path[2];
 	}
 	SetResultLength(resultPtr, offset, extended);
@@ -180,9 +180,9 @@ ExtractWinRoot(
 		break;
 	    }
 	}
-	Tcl_DStringAppend(resultPtr, "//", 2);
+	TclDStringAppendLiteral(resultPtr, "//");
 	Tcl_DStringAppend(resultPtr, host, hlen);
-	Tcl_DStringAppend(resultPtr, "/", 1);
+	TclDStringAppendLiteral(resultPtr, "/");
 	Tcl_DStringAppend(resultPtr, share, slen);
 
 	tail = &share[slen];
@@ -221,7 +221,7 @@ ExtractWinRoot(
 
 	    *typePtr = TCL_PATH_ABSOLUTE;
 	    Tcl_DStringAppend(resultPtr, path, 2);
-	    Tcl_DStringAppend(resultPtr, "/", 1);
+	    TclDStringAppendLiteral(resultPtr, "/");
 
 	    return tail;
 	}
@@ -1057,7 +1057,7 @@ Tcl_TranslateFileName(
     }
 
     Tcl_DStringInit(bufferPtr);
-    Tcl_DStringAppend(bufferPtr, Tcl_GetString(transPtr), -1);
+    TclDStringAppendObj(bufferPtr, transPtr);
     Tcl_DecrRefCount(path);
     Tcl_DecrRefCount(transPtr);
 
@@ -1413,7 +1413,7 @@ Tcl_GlobObjCmd(
 	    search = Tcl_DStringValue(&pref);
 	    while ((find = (strpbrk(search, "\\[]*?{}"))) != NULL) {
 		Tcl_DStringAppend(&prefix, search, find-search);
-		Tcl_DStringAppend(&prefix, "\\", 1);
+		TclDStringAppendLiteral(&prefix, "\\");
 		Tcl_DStringAppend(&prefix, find, 1);
 		search = find+1;
 		if (*search == '\0') {
@@ -1575,8 +1575,7 @@ Tcl_GlobObjCmd(
 	    Tcl_DStringInit(&prefix);
 	}
 	for (i = 0; i < objc; i++) {
-	    string = Tcl_GetStringFromObj(objv[i], &length);
-	    Tcl_DStringAppend(&prefix, string, length);
+	    TclDStringAppendObj(&prefix, objv[i]);
 	    if (i != objc -1) {
 		Tcl_DStringAppend(&prefix, separators, 1);
 	    }
@@ -1592,11 +1591,9 @@ Tcl_GlobObjCmd(
 	for (i = 0; i < objc; i++) {
 	    Tcl_DStringInit(&str);
 	    if (dir == PATH_GENERAL) {
-		Tcl_DStringAppend(&str, Tcl_DStringValue(&prefix),
-			Tcl_DStringLength(&prefix));
+		TclDStringAppendDString(&str, &prefix);
 	    }
-	    string = Tcl_GetStringFromObj(objv[i], &length);
-	    Tcl_DStringAppend(&str, string, length);
+	    TclDStringAppendObj(&str, objv[i]);
 	    if (TclGlob(interp, Tcl_DStringValue(&str), pathOrDir, globFlags,
 		    globTypes) != TCL_OK) {
 		result = TCL_ERROR;
@@ -2401,9 +2398,9 @@ DoGlob(
 	    if (length == 0 && (Tcl_DStringLength(&append) == 0)) {
 		if (((*name == '\\') && (name[1] == '/' ||
 			name[1] == '\\')) || (*name == '/')) {
-		    Tcl_DStringAppend(&append, "/", 1);
+		    TclDStringAppendLiteral(&append, "/");
 		} else {
-		    Tcl_DStringAppend(&append, ".", 1);
+		    TclDStringAppendLiteral(&append, ".");
 		}
 	    }
 
@@ -2412,9 +2409,9 @@ DoGlob(
 	case TCL_PLATFORM_UNIX:
 	    if (length == 0 && (Tcl_DStringLength(&append) == 0)) {
 		if ((*name == '\\' && name[1] == '/') || (*name == '/')) {
-		    Tcl_DStringAppend(&append, "/", 1);
+		    TclDStringAppendLiteral(&append, "/");
 		} else {
-		    Tcl_DStringAppend(&append, ".", 1);
+		    TclDStringAppendLiteral(&append, ".");
 		}
 	    }
 	    break;
diff --git a/generic/tclFileSystem.h b/generic/tclFileSystem.h
index 088bf85..6be3e03 100644
--- a/generic/tclFileSystem.h
+++ b/generic/tclFileSystem.h
@@ -16,44 +16,6 @@
 #include "tcl.h"
 
 /*
- * struct FilesystemRecord --
- *
- * A filesystem record is used to keep track of each filesystem currently
- * registered with the core, in a linked list. Pointers to these structures
- * are also kept by each "path" Tcl_Obj, and we must retain a refCount on the
- * number of such references.
- */
-
-typedef struct FilesystemRecord {
-    ClientData clientData;	/* Client specific data for the new filesystem
-				 * (can be NULL) */
-    const Tcl_Filesystem *fsPtr;	/* Pointer to filesystem dispatch table. */
-    struct FilesystemRecord *nextPtr;
-				/* The next filesystem registered to Tcl, or
-				 * NULL if no more. */
-    struct FilesystemRecord *prevPtr;
-				/* The previous filesystem registered to Tcl,
-				 * or NULL if no more. */
-} FilesystemRecord;
-
-/*
- * This structure holds per-thread private copy of the current directory
- * maintained by the global cwdPathPtr. This structure holds per-thread
- * private copies of some global data. This way we avoid most of the
- * synchronization calls which boosts performance, at cost of having to update
- * this information each time the corresponding epoch counter changes.
- */
-
-typedef struct ThreadSpecificData {
-    int initialized;
-    int cwdPathEpoch;
-    int filesystemEpoch;
-    Tcl_Obj *cwdPathPtr;
-    ClientData cwdClientData;
-    FilesystemRecord *filesystemList;
-} ThreadSpecificData;
-
-/*
  * The internal TclFS API provides routines for handling and manipulating
  * paths efficiently, taking direct advantage of the "path" Tcl_Obj type.
  *
@@ -61,8 +23,6 @@ typedef struct ThreadSpecificData {
  */
 
 MODULE_SCOPE int	TclFSCwdPointerEquals(Tcl_Obj **pathPtrPtr);
-MODULE_SCOPE int	TclFSMakePathFromNormalized(Tcl_Interp *interp,
-			    Tcl_Obj *pathPtr);
 MODULE_SCOPE int	TclFSNormalizeToUniquePath(Tcl_Interp *interp,
 			    Tcl_Obj *pathPtr, int startAt);
 MODULE_SCOPE Tcl_Obj *	TclFSMakePathRelative(Tcl_Interp *interp,
@@ -73,13 +33,13 @@ MODULE_SCOPE void	TclFSSetPathDetails(Tcl_Obj *pathPtr,
 			    const Tcl_Filesystem *fsPtr, ClientData clientData);
 MODULE_SCOPE Tcl_Obj *	TclFSNormalizeAbsolutePath(Tcl_Interp *interp,
 			    Tcl_Obj *pathPtr);
+MODULE_SCOPE int	TclFSEpoch(void);
 
 /*
  * Private shared variables for use by tclIOUtil.c and tclPathObj.c
  */
 
 MODULE_SCOPE const Tcl_Filesystem tclNativeFilesystem;
-MODULE_SCOPE Tcl_ThreadDataKey tclFsDataKey;
 
 /*
  * Private shared functions for use by tclIOUtil.c, tclPathObj.c and
diff --git a/generic/tclIO.c b/generic/tclIO.c
index a76aba3..ea6c2d7 100644
--- a/generic/tclIO.c
+++ b/generic/tclIO.c
@@ -4431,14 +4431,12 @@ Tcl_Gets(
 				 * for managing the storage. */
 {
     Tcl_Obj *objPtr;
-    int charsStored, length;
-    const char *string;
+    int charsStored;
 
     TclNewObj(objPtr);
     charsStored = Tcl_GetsObj(chan, objPtr);
     if (charsStored > 0) {
-	string = TclGetStringFromObj(objPtr, &length);
-	Tcl_DStringAppend(lineRead, string, length);
+	TclDStringAppendObj(lineRead, objPtr);
     }
     TclDecrRefCount(objPtr);
     return charsStored;
@@ -7550,7 +7548,7 @@ Tcl_BadChannelOption(
 	Tcl_DStringInit(&ds);
 	Tcl_DStringAppend(&ds, genericopt, -1);
 	if (optionList && (*optionList)) {
-	    Tcl_DStringAppend(&ds, " ", 1);
+	    TclDStringAppendLiteral(&ds, " ");
 	    Tcl_DStringAppend(&ds, optionList, -1);
 	}
 	if (Tcl_SplitList(interp, Tcl_DStringValue(&ds),
diff --git a/generic/tclIORChan.c b/generic/tclIORChan.c
index 938def2..6fec40a 100644
--- a/generic/tclIORChan.c
+++ b/generic/tclIORChan.c
@@ -1947,7 +1947,7 @@ ReflectGetOption(
      */
 
     if (optionObj != NULL) {
-	Tcl_DStringAppend(dsPtr, TclGetString(resObj), -1);
+	TclDStringAppendObj(dsPtr, resObj);
         goto ok;
     }
 
@@ -1982,7 +1982,7 @@ ReflectGetOption(
 	const char *str = Tcl_GetStringFromObj(resObj, &len);
 
 	if (len) {
-	    Tcl_DStringAppend(dsPtr, " ", 1);
+	    TclDStringAppendLiteral(dsPtr, " ");
 	    Tcl_DStringAppend(dsPtr, str, len);
 	}
         goto ok;
@@ -3207,8 +3207,7 @@ ForwardProc(
 	if (InvokeTclMethod(rcPtr, "cget", optionObj, NULL, &resObj)!=TCL_OK){
 	    ForwardSetObjError(paramPtr, resObj);
 	} else {
-	    Tcl_DStringAppend(paramPtr->getOpt.value,
-                              TclGetString(resObj), -1);
+	    TclDStringAppendObj(paramPtr->getOpt.value, resObj);
 	}
         Tcl_Release(rcPtr);
         Tcl_DecrRefCount(optionObj);
@@ -3233,7 +3232,7 @@ ForwardProc(
 	    Tcl_Obj **listv;
 
 	    if (Tcl_ListObjGetElements(interp, resObj, &listc,
-                                       &listv) != TCL_OK) {
+                    &listv) != TCL_OK) {
 		Tcl_DecrRefCount(resObj);
 		resObj = MarshallError(interp);
 		ForwardSetObjError(paramPtr, resObj);
@@ -3253,7 +3252,7 @@ ForwardProc(
 		const char *str = Tcl_GetStringFromObj(resObj, &len);
 
 		if (len) {
-		    Tcl_DStringAppend(paramPtr->getOpt.value, " ", 1);
+		    TclDStringAppendLiteral(paramPtr->getOpt.value, " ");
 		    Tcl_DStringAppend(paramPtr->getOpt.value, str, len);
 		}
 	    }
diff --git a/generic/tclIOSock.c b/generic/tclIOSock.c
index 6a7be7e..018f9f5 100644
--- a/generic/tclIOSock.c
+++ b/generic/tclIOSock.c
@@ -100,16 +100,16 @@ TclSockMinimumBuffers(
     socklen_t len;
 
     len = sizeof(int);
-    getsockopt((SOCKET)sock, SOL_SOCKET, SO_SNDBUF, (char *)&current, &len);
+    getsockopt((SOCKET)(size_t)sock, SOL_SOCKET, SO_SNDBUF, (char *)&current, &len);
     if (current < size) {
 	len = sizeof(int);
-	setsockopt((SOCKET)sock, SOL_SOCKET, SO_SNDBUF, (char *)&size, len);
+	setsockopt((SOCKET)(size_t)sock, SOL_SOCKET, SO_SNDBUF, (char *)&size, len);
     }
     len = sizeof(int);
-    getsockopt((SOCKET)sock, SOL_SOCKET, SO_RCVBUF, (char *)&current, &len);
+    getsockopt((SOCKET)(size_t)sock, SOL_SOCKET, SO_RCVBUF, (char *)&current, &len);
     if (current < size) {
 	len = sizeof(int);
-	setsockopt((SOCKET)sock, SOL_SOCKET, SO_RCVBUF, (char *)&size, len);
+	setsockopt((SOCKET)(size_t)sock, SOL_SOCKET, SO_RCVBUF, (char *)&size, len);
     }
     return TCL_OK;
 }
@@ -206,9 +206,12 @@ TclCreateSocketAddress(
     }
 
     if (result != 0) {
-        if (result != EAI_SYSTEM) {
+#ifdef EAI_SYSTEM /* Doesn't exist on Windows */
+        if (result == EAI_SYSTEM)
+            *errorMsgPtr = Tcl_PosixError(interp);
+        else
+#endif
             *errorMsgPtr = gai_strerror(result);
-        }
         return 0;
     }
 
diff --git a/generic/tclIOUtil.c b/generic/tclIOUtil.c
index b8bb0f7..41a5aac 100644
--- a/generic/tclIOUtil.c
+++ b/generic/tclIOUtil.c
@@ -28,6 +28,43 @@
 #include "tclFileSystem.h"
 
 /*
+ * struct FilesystemRecord --
+ *
+ * A filesystem record is used to keep track of each filesystem currently
+ * registered with the core, in a linked list.
+ */
+
+typedef struct FilesystemRecord {
+    ClientData clientData;	/* Client specific data for the new filesystem
+				 * (can be NULL) */
+    const Tcl_Filesystem *fsPtr;/* Pointer to filesystem dispatch table. */
+    struct FilesystemRecord *nextPtr;
+				/* The next filesystem registered to Tcl, or
+				 * NULL if no more. */
+    struct FilesystemRecord *prevPtr;
+				/* The previous filesystem registered to Tcl,
+				 * or NULL if no more. */
+} FilesystemRecord;
+
+/*
+ * This structure holds per-thread private copy of the current directory
+ * maintained by the global cwdPathPtr. This structure holds per-thread
+ * private copies of some global data. This way we avoid most of the
+ * synchronization calls which boosts performance, at cost of having to update
+ * this information each time the corresponding epoch counter changes.
+ */
+
+typedef struct ThreadSpecificData {
+    int initialized;
+    int cwdPathEpoch;
+    int filesystemEpoch;
+    Tcl_Obj *cwdPathPtr;
+    ClientData cwdClientData;
+    FilesystemRecord *filesystemList;
+    int claims;
+} ThreadSpecificData;
+
+/*
  * Prototypes for functions defined later in this file.
  */
 
@@ -40,9 +77,10 @@ static void		FsAddMountsToGlobResult(Tcl_Obj *resultPtr,
 			    Tcl_Obj *pathPtr, const char *pattern,
 			    Tcl_GlobTypeData *types);
 static void		FsUpdateCwd(Tcl_Obj *cwdObj, ClientData clientData);
-#ifdef TCL_THREADS
 static void		FsRecacheFilesystemList(void);
-#endif
+static void		Claim(void);
+static void		Disclaim(void);
+
 static void *		DivertFindSymbol(Tcl_Interp *interp,
 			    Tcl_LoadHandle loadHandle, const char *symbol);
 static void		DivertUnloadFile(Tcl_LoadHandle loadHandle);
@@ -174,7 +212,7 @@ static FilesystemRecord nativeFilesystemRecord = {
  * trigger cache cleanup in all threads.
  */
 
-static int theFilesystemEpoch = 0;
+static int theFilesystemEpoch = 1;
 
 /*
  * Stores the linked list of filesystems. A 1:1 copy of this list is also
@@ -194,7 +232,7 @@ static int cwdPathEpoch = 0;
 static ClientData cwdClientData = NULL;
 TCL_DECLARE_MUTEX(cwdMutex)
 
-Tcl_ThreadDataKey tclFsDataKey;
+static Tcl_ThreadDataKey fsDataKey;
 
 /*
  * One of these structures is used each time we successfully load a file from
@@ -367,7 +405,7 @@ Tcl_GetCwd(
 	return NULL;
     }
     Tcl_DStringInit(cwdPtr);
-    Tcl_DStringAppend(cwdPtr, Tcl_GetString(cwd), -1);
+    TclDStringAppendObj(cwdPtr, cwd);
     Tcl_DecrRefCount(cwd);
     return Tcl_DStringValue(cwdPtr);
 }
@@ -428,7 +466,7 @@ FsThrExitProc(
 int
 TclFSCwdIsNative(void)
 {
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
 
     if (tsdPtr->cwdClientData != NULL) {
 	return 1;
@@ -462,7 +500,7 @@ int
 TclFSCwdPointerEquals(
     Tcl_Obj **pathPtrPtr)
 {
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
 
     Tcl_MutexLock(&cwdMutex);
     if (tsdPtr->cwdPathPtr == NULL
@@ -521,12 +559,11 @@ TclFSCwdPointerEquals(
     }
 }
 
-#ifdef TCL_THREADS
 static void
 FsRecacheFilesystemList(void)
 {
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
-    FilesystemRecord *fsRecPtr, *tmpFsRecPtr = NULL, *toFree = NULL;
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
+    FilesystemRecord *fsRecPtr, *tmpFsRecPtr = NULL, *toFree = NULL, *list;
 
     /*
      * Trash the current cache.
@@ -535,20 +572,16 @@ FsRecacheFilesystemList(void)
     fsRecPtr = tsdPtr->filesystemList;
     while (fsRecPtr != NULL) {
 	tmpFsRecPtr = fsRecPtr->nextPtr;
-	fsRecPtr->fsPtr = NULL;
 	fsRecPtr->nextPtr = toFree;
 	toFree = fsRecPtr;
 	fsRecPtr = tmpFsRecPtr;
     }
-    tsdPtr->filesystemList = NULL;
 
     /*
-     * Code below operates on shared data. We are already called under mutex
-     * lock so we can safely proceed.
-     *
      * Locate tail of the global filesystem list.
      */
 
+    Tcl_MutexLock(&filesystemMutex);
     fsRecPtr = filesystemList;
     while (fsRecPtr != NULL) {
 	tmpFsRecPtr = fsRecPtr;
@@ -559,21 +592,23 @@ FsRecacheFilesystemList(void)
      * Refill the cache honouring the order.
      */
 
+    list = NULL;
     fsRecPtr = tmpFsRecPtr;
     while (fsRecPtr != NULL) {
 	tmpFsRecPtr = ckalloc(sizeof(FilesystemRecord));
 	*tmpFsRecPtr = *fsRecPtr;
-	tmpFsRecPtr->nextPtr = tsdPtr->filesystemList;
+	tmpFsRecPtr->nextPtr = list;
 	tmpFsRecPtr->prevPtr = NULL;
-	if (tsdPtr->filesystemList) {
-	    tsdPtr->filesystemList->prevPtr = tmpFsRecPtr;
-	}
-	tsdPtr->filesystemList = tmpFsRecPtr;
+	list = tmpFsRecPtr;
 	fsRecPtr = fsRecPtr->prevPtr;
     }
+    tsdPtr->filesystemList = list;
+    tsdPtr->filesystemEpoch = theFilesystemEpoch;
+    Tcl_MutexUnlock(&filesystemMutex);
 
     while (toFree) {
 	FilesystemRecord *next = toFree->nextPtr;
+	toFree->fsPtr = NULL;
 	ckfree(toFree);
 	toFree = next;
     }
@@ -587,28 +622,16 @@ FsRecacheFilesystemList(void)
 	tsdPtr->initialized = 1;
     }
 }
-#endif /* TCL_THREADS */
 
 static FilesystemRecord *
 FsGetFirstFilesystem(void)
 {
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
-    FilesystemRecord *fsRecPtr;
-
-#ifndef TCL_THREADS
-    tsdPtr->filesystemEpoch = theFilesystemEpoch;
-    fsRecPtr = filesystemList;
-#else
-    Tcl_MutexLock(&filesystemMutex);
-    if (tsdPtr->filesystemList == NULL
-	    || (tsdPtr->filesystemEpoch != theFilesystemEpoch)) {
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
+    if (tsdPtr->filesystemList == NULL || ((tsdPtr->claims == 0)
+	    && (tsdPtr->filesystemEpoch != theFilesystemEpoch))) {
 	FsRecacheFilesystemList();
-	tsdPtr->filesystemEpoch = theFilesystemEpoch;
     }
-    Tcl_MutexUnlock(&filesystemMutex);
-    fsRecPtr = tsdPtr->filesystemList;
-#endif
-    return fsRecPtr;
+    return tsdPtr->filesystemList;
 }
 
 /*
@@ -620,11 +643,30 @@ int
 TclFSEpochOk(
     int filesystemEpoch)
 {
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
+    return (filesystemEpoch == 0 || filesystemEpoch == theFilesystemEpoch);
+}
+
+static void
+Claim()
+{
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
+    tsdPtr->claims++;
+}
+
+static void
+Disclaim()
+{
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
+    tsdPtr->claims--;
+}
 
-    (void) FsGetFirstFilesystem();
-    return (filesystemEpoch == tsdPtr->filesystemEpoch);
+int
+TclFSEpoch()
+{
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
+    return tsdPtr->filesystemEpoch;
 }
+
 
 /*
  * If non-NULL, clientData is owned by us and must be freed later.
@@ -637,7 +679,7 @@ FsUpdateCwd(
 {
     int len;
     const char *str = NULL;
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
 
     if (cwdObj != NULL) {
 	str = Tcl_GetStringFromObj(cwdObj, &len);
@@ -741,6 +783,7 @@ TclFinalizeFilesystem(void)
 	}
 	fsRecPtr = tmpFsRecPtr;
     }
+    theFilesystemEpoch++;
     filesystemList = NULL;
 
     /*
@@ -773,6 +816,7 @@ void
 TclResetFilesystem(void)
 {
     filesystemList = &nativeFilesystemRecord;
+    theFilesystemEpoch++;
 
 #ifdef __WIN32__
     /*
@@ -1345,6 +1389,7 @@ TclFSNormalizeToUniquePath(
 
     firstFsRecPtr = FsGetFirstFilesystem();
 
+    Claim();
     for (fsRecPtr=firstFsRecPtr; fsRecPtr!=NULL; fsRecPtr=fsRecPtr->nextPtr) {
 	if (fsRecPtr->fsPtr != &tclNativeFilesystem) {
 	    continue;
@@ -1382,6 +1427,7 @@ TclFSNormalizeToUniquePath(
 	 * but there's not much benefit.
 	 */
     }
+    Disclaim();
 
     return startAt;
 }
@@ -2576,7 +2622,7 @@ Tcl_Obj *
 Tcl_FSGetCwd(
     Tcl_Interp *interp)
 {
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
+    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
 
     if (TclFSCwdPointerEquals(NULL)) {
 	FilesystemRecord *fsRecPtr;
@@ -2588,8 +2634,9 @@ Tcl_FSGetCwd(
 	 * indicates the particular function has succeeded.
 	 */
 
-	for (fsRecPtr = FsGetFirstFilesystem();
-		(retVal == NULL) && (fsRecPtr != NULL);
+	fsRecPtr = FsGetFirstFilesystem();
+	Claim();
+	for (; (retVal == NULL) && (fsRecPtr != NULL);
 		fsRecPtr = fsRecPtr->nextPtr) {
 	    ClientData retCd;
 	    TclFSGetCwdProc2 *proc2;
@@ -2634,6 +2681,7 @@ Tcl_FSGetCwd(
 		}
 		Tcl_DecrRefCount(retVal);
 		retVal = NULL;
+		Disclaim();
 		goto cdDidNotChange;
 	    } else if (interp != NULL) {
 		Tcl_AppendResult(interp,
@@ -2641,6 +2689,7 @@ Tcl_FSGetCwd(
 			Tcl_PosixError(interp), NULL);
 	    }
 	}
+	Disclaim();
 
 	/*
 	 * Now the 'cwd' may NOT be normalized, at least on some platforms.
@@ -2924,7 +2973,7 @@ Tcl_FSChdir(
 	     * instead. This should be examined by someone on Unix.
 	     */
 
-	    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
+	    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
 	    ClientData cd;
 	    ClientData oldcd = tsdPtr->cwdClientData;
 
@@ -3761,6 +3810,7 @@ Tcl_FSListVolumes(void)
      */
 
     fsRecPtr = FsGetFirstFilesystem();
+    Claim();
     while (fsRecPtr != NULL) {
 	if (fsRecPtr->fsPtr->listVolumesProc != NULL) {
 	    Tcl_Obj *thisFsVolumes = fsRecPtr->fsPtr->listVolumesProc();
@@ -3772,6 +3822,7 @@ Tcl_FSListVolumes(void)
 	}
 	fsRecPtr = fsRecPtr->nextPtr;
     }
+    Disclaim();
 
     return resultPtr;
 }
@@ -3811,6 +3862,7 @@ FsListMounts(
      */
 
     fsRecPtr = FsGetFirstFilesystem();
+    Claim();
     while (fsRecPtr != NULL) {
 	if (fsRecPtr->fsPtr != &tclNativeFilesystem &&
 		fsRecPtr->fsPtr->matchInDirectoryProc != NULL) {
@@ -3822,6 +3874,7 @@ FsListMounts(
 	}
 	fsRecPtr = fsRecPtr->nextPtr;
     }
+    Disclaim();
 
     return resultPtr;
 }
@@ -4034,6 +4087,7 @@ TclFSNonnativePathType(
      */
 
     fsRecPtr = FsGetFirstFilesystem();
+    Claim();
     while (fsRecPtr != NULL) {
 	/*
 	 * We want to skip the native filesystem in this loop because
@@ -4111,6 +4165,7 @@ TclFSNonnativePathType(
 	}
 	fsRecPtr = fsRecPtr->nextPtr;
     }
+    Disclaim();
     return type;
 }
 
@@ -4498,10 +4553,14 @@ Tcl_FSGetFileSystemForPath(
      */
 
     fsRecPtr = FsGetFirstFilesystem();
+    Claim();
+
     if (TclFSEnsureEpochOk(pathPtr, &retVal) != TCL_OK) {
+	Disclaim();
 	return NULL;
     } else if (retVal != NULL) {
 	/* TODO: Can this happen? */
+	Disclaim();
 	return retVal;
     }
 
@@ -4524,9 +4583,11 @@ Tcl_FSGetFileSystemForPath(
 	     */
 
 	    TclFSSetPathDetails(pathPtr, fsRecPtr->fsPtr, clientData);
+	    Disclaim();
 	    return fsRecPtr->fsPtr;
 	}
     }
+    Disclaim();
 
     return NULL;
 }
diff --git a/generic/tclInt.decls b/generic/tclInt.decls
index 97517ea..9f73a31 100644
--- a/generic/tclInt.decls
+++ b/generic/tclInt.decls
@@ -1095,6 +1095,11 @@ declare 16 win {
 #  declare 17 win {
 #      char *TclpGetTZName(void)
 #  }
+# new for 8.5.12+ Cygwin only
+declare 17 win {
+    int TclUnixCopyFile(const char *src, const char *dst,
+	    const Tcl_StatBuf *statBufPtr, int dontCopyAtts)
+}
 declare 18 win {
     TclFile TclpMakeFile(Tcl_Channel channel, int direction)
 }
diff --git a/generic/tclInt.h b/generic/tclInt.h
index 9068dfb..53a88d6 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -2920,6 +2920,10 @@ MODULE_SCOPE void	TclCreateLateExitHandler(Tcl_ExitProc *proc,
 			    ClientData clientData);
 MODULE_SCOPE void	TclDeleteLateExitHandler(Tcl_ExitProc *proc,
 			    ClientData clientData);
+MODULE_SCOPE char *	TclDStringAppendObj(Tcl_DString *dsPtr,
+			    Tcl_Obj *objPtr);
+MODULE_SCOPE char *	TclDStringAppendDString(Tcl_DString *dsPtr,
+			    Tcl_DString *toAppendPtr);
 MODULE_SCOPE Tcl_Obj *	TclDStringToObj(Tcl_DString *dsPtr);
 MODULE_SCOPE void	TclFinalizeAllocSubsystem(void);
 MODULE_SCOPE void	TclFinalizeAsync(void);
@@ -4452,6 +4456,21 @@ MODULE_SCOPE Tcl_PackageInitProc Procbodytest_SafeInit;
 
 /*
  *----------------------------------------------------------------
+ * Convenience macros for DStrings.
+ * The ANSI C "prototypes" for these macros are:
+ *
+ * MODULE_SCOPE char * TclDStringAppendLiteral(Tcl_DString *dsPtr,
+ *			const char *sLiteral);
+ * MODULE_SCOPE void   TclDStringClear(Tcl_DString *dsPtr);
+ */
+
+#define TclDStringAppendLiteral(dsPtr, sLiteral) \
+    Tcl_DStringAppend((dsPtr), (sLiteral), (int) (sizeof(sLiteral "") - 1))
+#define TclDStringClear(dsPtr) \
+    Tcl_DStringSetLength((dsPtr), 0)
+
+/*
+ *----------------------------------------------------------------
  * Macros used by the Tcl core to test for some special double values.
  * The ANSI C "prototypes" for these macros are:
  *
diff --git a/generic/tclIntPlatDecls.h b/generic/tclIntPlatDecls.h
index a9c6e8c..7322a37 100644
--- a/generic/tclIntPlatDecls.h
+++ b/generic/tclIntPlatDecls.h
@@ -140,7 +140,10 @@ EXTERN int		TclpCreateProcess(Tcl_Interp *interp, int argc,
 				Tcl_Pid *pidPtr);
 /* 16 */
 EXTERN int		TclpIsAtty(int fd);
-/* Slot 17 is reserved */
+/* 17 */
+EXTERN int		TclUnixCopyFile(const char *src, const char *dst,
+				const Tcl_StatBuf *statBufPtr,
+				int dontCopyAtts);
 /* 18 */
 EXTERN TclFile		TclpMakeFile(Tcl_Channel channel, int direction);
 /* 19 */
@@ -289,7 +292,7 @@ typedef struct TclIntPlatStubs {
     int (*tclpCreatePipe) (TclFile *readPipe, TclFile *writePipe); /* 14 */
     int (*tclpCreateProcess) (Tcl_Interp *interp, int argc, const char **argv, TclFile inputFile, TclFile outputFile, TclFile errorFile, Tcl_Pid *pidPtr); /* 15 */
     int (*tclpIsAtty) (int fd); /* 16 */
-    void (*reserved17)(void);
+    int (*tclUnixCopyFile) (const char *src, const char *dst, const Tcl_StatBuf *statBufPtr, int dontCopyAtts); /* 17 */
     TclFile (*tclpMakeFile) (Tcl_Channel channel, int direction); /* 18 */
     TclFile (*tclpOpenFile) (const char *fname, int mode); /* 19 */
     void (*tclWinAddProcess) (HANDLE hProcess, DWORD id); /* 20 */
@@ -433,7 +436,8 @@ extern const TclIntPlatStubs *tclIntPlatStubsPtr;
 	(tclIntPlatStubsPtr->tclpCreateProcess) /* 15 */
 #define TclpIsAtty \
 	(tclIntPlatStubsPtr->tclpIsAtty) /* 16 */
-/* Slot 17 is reserved */
+#define TclUnixCopyFile \
+	(tclIntPlatStubsPtr->tclUnixCopyFile) /* 17 */
 #define TclpMakeFile \
 	(tclIntPlatStubsPtr->tclpMakeFile) /* 18 */
 #define TclpOpenFile \
diff --git a/generic/tclLoad.c b/generic/tclLoad.c
index 008a99d..ce4d6a4 100644
--- a/generic/tclLoad.c
+++ b/generic/tclLoad.c
@@ -198,9 +198,9 @@ Tcl_LoadObjCmd(
 	if (packageName == NULL) {
 	    namesMatch = 0;
 	} else {
-	    Tcl_DStringSetLength(&pkgName, 0);
+	    TclDStringClear(&pkgName);
 	    Tcl_DStringAppend(&pkgName, packageName, -1);
-	    Tcl_DStringSetLength(&tmp, 0);
+	    TclDStringClear(&tmp);
 	    Tcl_DStringAppend(&tmp, pkgPtr->packageName, -1);
 	    Tcl_UtfToLower(Tcl_DStringValue(&pkgName));
 	    Tcl_UtfToLower(Tcl_DStringValue(&tmp));
@@ -211,7 +211,7 @@ Tcl_LoadObjCmd(
 		namesMatch = 0;
 	    }
 	}
-	Tcl_DStringSetLength(&pkgName, 0);
+	TclDStringClear(&pkgName);
 
 	filesMatch = (strcmp(pkgPtr->fileName, fullFileName) == 0);
 	if (filesMatch && (namesMatch || (packageName == NULL))) {
@@ -329,7 +329,7 @@ Tcl_LoadObjCmd(
 		    code = TCL_ERROR;
 		    goto done;
 		}
-		Tcl_DStringAppend(&pkgName, pkgGuess, (p - pkgGuess));
+		Tcl_DStringAppend(&pkgName, pkgGuess, p - pkgGuess);
 		Tcl_DecrRefCount(splitPtr);
 	    }
 	}
@@ -348,14 +348,14 @@ Tcl_LoadObjCmd(
 	 * package name.
 	 */
 
-	Tcl_DStringAppend(&initName, Tcl_DStringValue(&pkgName), -1);
-	Tcl_DStringAppend(&initName, "_Init", 5);
-	Tcl_DStringAppend(&safeInitName, Tcl_DStringValue(&pkgName), -1);
-	Tcl_DStringAppend(&safeInitName, "_SafeInit", 9);
-	Tcl_DStringAppend(&unloadName, Tcl_DStringValue(&pkgName), -1);
-	Tcl_DStringAppend(&unloadName, "_Unload", 7);
-	Tcl_DStringAppend(&safeUnloadName, Tcl_DStringValue(&pkgName), -1);
-	Tcl_DStringAppend(&safeUnloadName, "_SafeUnload", 11);
+	TclDStringAppendDString(&initName, &pkgName);
+	TclDStringAppendLiteral(&initName, "_Init");
+	TclDStringAppendDString(&safeInitName, &pkgName);
+	TclDStringAppendLiteral(&safeInitName, "_SafeInit");
+	TclDStringAppendDString(&unloadName, &pkgName);
+	TclDStringAppendLiteral(&unloadName, "_Unload");
+	TclDStringAppendDString(&safeUnloadName, &pkgName);
+	TclDStringAppendLiteral(&safeUnloadName, "_SafeUnload");
 
 	/*
 	 * Call platform-specific code to load the package and find the two
@@ -623,9 +623,9 @@ Tcl_UnloadObjCmd(
 	if (packageName == NULL) {
 	    namesMatch = 0;
 	} else {
-	    Tcl_DStringSetLength(&pkgName, 0);
+	    TclDStringClear(&pkgName);
 	    Tcl_DStringAppend(&pkgName, packageName, -1);
-	    Tcl_DStringSetLength(&tmp, 0);
+	    TclDStringClear(&tmp);
 	    Tcl_DStringAppend(&tmp, pkgPtr->packageName, -1);
 	    Tcl_UtfToLower(Tcl_DStringValue(&pkgName));
 	    Tcl_UtfToLower(Tcl_DStringValue(&tmp));
@@ -636,7 +636,7 @@ Tcl_UnloadObjCmd(
 		namesMatch = 0;
 	    }
 	}
-	Tcl_DStringSetLength(&pkgName, 0);
+	TclDStringClear(&pkgName);
 
 	filesMatch = (strcmp(pkgPtr->fileName, fullFileName) == 0);
 	if (filesMatch && (namesMatch || (packageName == NULL))) {
diff --git a/generic/tclNamesp.c b/generic/tclNamesp.c
index 73bc644..6a241f0 100644
--- a/generic/tclNamesp.c
+++ b/generic/tclNamesp.c
@@ -24,7 +24,7 @@
  */
 
 #include "tclInt.h"
-#include "tclCompile.h" /* for NRCommand; and TclLogCommandInfo visibility */
+#include "tclCompile.h" /* for TclLogCommandInfo visibility */
 
 /*
  * Thread-local storage used to avoid having a global lock on data that is not
@@ -803,10 +803,9 @@ Tcl_CreateNamespace(
 	if (ancestorPtr != globalNsPtr) {
 	    register Tcl_DString *tempPtr = namePtr;
 
-	    Tcl_DStringAppend(buffPtr, "::", 2);
+	    TclDStringAppendLiteral(buffPtr, "::");
 	    Tcl_DStringAppend(buffPtr, ancestorPtr->name, -1);
-	    Tcl_DStringAppend(buffPtr, Tcl_DStringValue(namePtr),
-		    Tcl_DStringLength(namePtr));
+	    TclDStringAppendDString(buffPtr, namePtr);
 
 	    /*
 	     * Clear the unwanted buffer or we end up appending to previous
@@ -814,7 +813,7 @@ Tcl_CreateNamespace(
 	     * very wrong (and strange).
 	     */
 
-	    Tcl_DStringSetLength(namePtr, 0);
+	    TclDStringClear(namePtr);
 
 	    /*
 	     * Now swap the buffer pointers so that we build in the other
@@ -916,7 +915,7 @@ Tcl_DeleteNamespace(
     for (entryPtr = Tcl_FirstHashEntry(&nsPtr->cmdTable, &search);
 	    entryPtr != NULL;) {
 	cmdPtr = Tcl_GetHashValue(entryPtr);
-	if (cmdPtr->nreProc == NRInterpCoroutine) {
+	if (cmdPtr->nreProc == TclNRInterpCoroutine) {
 	    Tcl_DeleteCommandFromToken((Tcl_Interp *) iPtr,
 		    (Tcl_Command) cmdPtr);
 	    entryPtr = Tcl_FirstHashEntry(&nsPtr->cmdTable, &search);
@@ -1667,7 +1666,7 @@ DoImport(
 	Tcl_DStringInit(&ds);
 	Tcl_DStringAppend(&ds, nsPtr->fullName, -1);
 	if (nsPtr != ((Interp *) interp)->globalNsPtr) {
-	    Tcl_DStringAppend(&ds, "::", 2);
+	    TclDStringAppendLiteral(&ds, "::");
 	}
 	Tcl_DStringAppend(&ds, cmdName, -1);
 
@@ -2241,7 +2240,7 @@ TclGetNamespaceForQualName(
 	     * qualName since it may be a string constant.
 	     */
 
-	    Tcl_DStringSetLength(&buffer, 0);
+	    TclDStringClear(&buffer);
 	    Tcl_DStringAppend(&buffer, start, len);
 	    nsName = Tcl_DStringValue(&buffer);
 	}
@@ -2916,7 +2915,7 @@ NamespaceChildrenCmd(
 	} else {
 	    Tcl_DStringAppend(&buffer, nsPtr->fullName, -1);
 	    if (nsPtr != globalNsPtr) {
-		Tcl_DStringAppend(&buffer, "::", 2);
+		TclDStringAppendLiteral(&buffer, "::");
 	    }
 	    Tcl_DStringAppend(&buffer, name, -1);
 	    pattern = Tcl_DStringValue(&buffer);
diff --git a/generic/tclOO.c b/generic/tclOO.c
index 26e6d75..821befd 100644
--- a/generic/tclOO.c
+++ b/generic/tclOO.c
@@ -356,14 +356,14 @@ InitFoundation(
 
     Tcl_DStringInit(&buffer);
     for (i=0 ; defineCmds[i].name ; i++) {
-	Tcl_DStringAppend(&buffer, "::oo::define::", 14);
+	TclDStringAppendLiteral(&buffer, "::oo::define::");
 	Tcl_DStringAppend(&buffer, defineCmds[i].name, -1);
 	Tcl_CreateObjCommand(interp, Tcl_DStringValue(&buffer),
 		defineCmds[i].objProc, INT2PTR(defineCmds[i].flag), NULL);
 	Tcl_DStringFree(&buffer);
     }
     for (i=0 ; objdefCmds[i].name ; i++) {
-	Tcl_DStringAppend(&buffer, "::oo::objdefine::", 17);
+	TclDStringAppendLiteral(&buffer, "::oo::objdefine::");
 	Tcl_DStringAppend(&buffer, objdefCmds[i].name, -1);
 	Tcl_CreateObjCommand(interp, Tcl_DStringValue(&buffer),
 		objdefCmds[i].objProc, INT2PTR(objdefCmds[i].flag), NULL);
@@ -657,7 +657,7 @@ AllocObject(
 	Tcl_DStringInit(&buffer);
 	Tcl_DStringAppend(&buffer,
 		Tcl_GetCurrentNamespace(interp)->fullName, -1);
-	Tcl_DStringAppend(&buffer, "::", 2);
+	TclDStringAppendLiteral(&buffer, "::");
 	Tcl_DStringAppend(&buffer, nameStr, -1);
 	oPtr->command = Tcl_CreateObjCommand(interp,
 		Tcl_DStringValue(&buffer), PublicObjectCmd, oPtr, NULL);
diff --git a/generic/tclOOBasic.c b/generic/tclOOBasic.c
index 5e983fc..35ad1eb 100644
--- a/generic/tclOOBasic.c
+++ b/generic/tclOOBasic.c
@@ -1190,7 +1190,7 @@ TclOOCopyObjectCmd(
 		Tcl_DStringAppend(&buffer,
 			iPtr->varFramePtr->nsPtr->fullName, -1);
 	    }
-	    Tcl_DStringAppend(&buffer, "::", 2);
+	    TclDStringAppendLiteral(&buffer, "::");
 	    Tcl_DStringAppend(&buffer, name, -1);
 	    name = Tcl_DStringValue(&buffer);
 	}
diff --git a/generic/tclPathObj.c b/generic/tclPathObj.c
index 06ee984..8bae4fb 100644
--- a/generic/tclPathObj.c
+++ b/generic/tclPathObj.c
@@ -27,6 +27,8 @@ static int		SetFsPathFromAny(Tcl_Interp *interp, Tcl_Obj *pathPtr);
 static int		FindSplitPos(const char *path, int separator);
 static int		IsSeparatorOrNull(int ch);
 static Tcl_Obj *	GetExtension(Tcl_Obj *pathPtr);
+static int		MakePathFromNormalized(Tcl_Interp *interp,
+			    Tcl_Obj *pathPtr);
 
 /*
  * Define the 'path' object type, which Tcl uses to represent file paths
@@ -432,7 +434,7 @@ TclFSNormalizeAbsolutePath(
      * object into an FsPath for greater efficiency
      */
 
-    TclFSMakePathFromNormalized(interp, retVal);
+    MakePathFromNormalized(interp, retVal);
 
     /*
      * This has a refCount of 1 for the caller, unlike many Tcl_Obj APIs.
@@ -564,8 +566,7 @@ TclPathPart(
     if (pathPtr->typePtr == &tclFsPathType) {
 	FsPath *fsPathPtr = PATHOBJ(pathPtr);
 
-	if (TclFSEpochOk(fsPathPtr->filesystemEpoch)
-		&& (PATHFLAGS(pathPtr) != 0)) {
+	if (PATHFLAGS(pathPtr) != 0) {
 	    switch (portion) {
 	    case TCL_PATH_DIRNAME: {
 		/*
@@ -1263,7 +1264,6 @@ TclNewFSPathObj(
 {
     FsPath *fsPathPtr;
     Tcl_Obj *pathPtr;
-    ThreadSpecificData *tsdPtr;
     const char *p;
     int state = 0, count = 0;
 
@@ -1291,8 +1291,6 @@ TclNewFSPathObj(
 	return pathPtr;
     }
 
-    tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
-
     pathPtr = Tcl_NewObj();
     fsPathPtr = ckalloc(sizeof(FsPath));
 
@@ -1307,7 +1305,7 @@ TclNewFSPathObj(
     Tcl_IncrRefCount(dirPtr);
     fsPathPtr->nativePathPtr = NULL;
     fsPathPtr->fsPtr = NULL;
-    fsPathPtr->filesystemEpoch = tsdPtr->filesystemEpoch;
+    fsPathPtr->filesystemEpoch = 0;
 
     SETPATHOBJ(pathPtr, fsPathPtr);
     PATHFLAGS(pathPtr) = TCLPATH_APPENDED;
@@ -1461,7 +1459,7 @@ TclFSMakePathRelative(
 /*
  *---------------------------------------------------------------------------
  *
- * TclFSMakePathFromNormalized --
+ * MakePathFromNormalized --
  *
  *	Like SetFsPathFromAny, but assumes the given object is an absolute
  *	normalized path. Only for internal use.
@@ -1475,13 +1473,12 @@ TclFSMakePathRelative(
  *---------------------------------------------------------------------------
  */
 
-int
-TclFSMakePathFromNormalized(
+static int
+MakePathFromNormalized(
     Tcl_Interp *interp,		/* Used for error reporting if not NULL. */
     Tcl_Obj *pathPtr)		/* The object to convert. */
 {
     FsPath *fsPathPtr;
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
 
     if (pathPtr->typePtr == &tclFsPathType) {
 	return TCL_OK;
@@ -1524,7 +1521,8 @@ TclFSMakePathFromNormalized(
     fsPathPtr->cwdPtr = NULL;
     fsPathPtr->nativePathPtr = NULL;
     fsPathPtr->fsPtr = NULL;
-    fsPathPtr->filesystemEpoch = tsdPtr->filesystemEpoch;
+    /* Remember the epoch under which we decided pathPtr was normalized */
+    fsPathPtr->filesystemEpoch = TclFSEpoch();
 
     SETPATHOBJ(pathPtr, fsPathPtr);
     PATHFLAGS(pathPtr) = 0;
@@ -1566,7 +1564,6 @@ Tcl_FSNewNativePath(
     Tcl_Obj *pathPtr = NULL;
     FsPath *fsPathPtr;
 
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
 
     if (fromFilesystem->internalToNormalizedProc != NULL) {
 	pathPtr = (*fromFilesystem->internalToNormalizedProc)(clientData);
@@ -1602,7 +1599,7 @@ Tcl_FSNewNativePath(
     fsPathPtr->cwdPtr = NULL;
     fsPathPtr->nativePathPtr = clientData;
     fsPathPtr->fsPtr = fromFilesystem;
-    fsPathPtr->filesystemEpoch = tsdPtr->filesystemEpoch;
+    fsPathPtr->filesystemEpoch = TclFSEpoch();
 
     SETPATHOBJ(pathPtr, fsPathPtr);
     PATHFLAGS(pathPtr) = 0;
@@ -1660,6 +1657,12 @@ Tcl_FSGetTranslatedPath(
 	    retObj = Tcl_FSJoinToPath(translatedCwdPtr, 1,
 		    &srcFsPathPtr->normPathPtr);
 	    srcFsPathPtr->translatedPathPtr = retObj;
+	    if (translatedCwdPtr->typePtr == &tclFsPathType) {
+		srcFsPathPtr->filesystemEpoch
+			= PATHOBJ(translatedCwdPtr)->filesystemEpoch;
+	    } else {
+		srcFsPathPtr->filesystemEpoch = 0;
+	    }
 	    Tcl_IncrRefCount(retObj);
 	    Tcl_DecrRefCount(translatedCwdPtr);
 	} else {
@@ -2203,7 +2206,6 @@ TclFSSetPathDetails(
     const Tcl_Filesystem *fsPtr,
     ClientData clientData)
 {
-    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
     FsPath *srcFsPathPtr;
 
     /*
@@ -2219,7 +2221,7 @@ TclFSSetPathDetails(
     srcFsPathPtr = PATHOBJ(pathPtr);
     srcFsPathPtr->fsPtr = fsPtr;
     srcFsPathPtr->nativePathPtr = clientData;
-    srcFsPathPtr->filesystemEpoch = tsdPtr->filesystemEpoch;
+    srcFsPathPtr->filesystemEpoch = TclFSEpoch();
 }
 
 /*
@@ -2308,7 +2310,6 @@ SetFsPathFromAny(
     FsPath *fsPathPtr;
     Tcl_Obj *transPtr;
     char *name;
-     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&tclFsDataKey);
 
     if (pathPtr->typePtr == &tclFsPathType) {
 	return TCL_OK;
@@ -2462,12 +2463,15 @@ SetFsPathFromAny(
     fsPathPtr->translatedPathPtr = transPtr;
     if (transPtr != pathPtr) {
 	Tcl_IncrRefCount(fsPathPtr->translatedPathPtr);
+	/* Redo translation when $env(HOME) changes */
+	fsPathPtr->filesystemEpoch = TclFSEpoch();
+    } else {
+	fsPathPtr->filesystemEpoch = 0;
     }
     fsPathPtr->normPathPtr = NULL;
     fsPathPtr->cwdPtr = NULL;
     fsPathPtr->nativePathPtr = NULL;
     fsPathPtr->fsPtr = NULL;
-    fsPathPtr->filesystemEpoch = tsdPtr->filesystemEpoch;
 
     /*
      * Free old representation before installing our new one.
diff --git a/generic/tclPkg.c b/generic/tclPkg.c
index fdaea57..382ffe3 100644
--- a/generic/tclPkg.c
+++ b/generic/tclPkg.c
@@ -1712,11 +1712,11 @@ AddRequirementsToDString(
 	int i;
 
 	for (i = 0; i < reqc; i++) {
-	    Tcl_DStringAppend(dsPtr, " ", 1);
-	    Tcl_DStringAppend(dsPtr, TclGetString(reqv[i]), -1);
+	    TclDStringAppendLiteral(dsPtr, " ");
+	    TclDStringAppendObj(dsPtr, reqv[i]);
 	}
     } else {
-	Tcl_DStringAppend(dsPtr, " 0-", -1);
+	TclDStringAppendLiteral(dsPtr, " 0-");
     }
 }
 
diff --git a/generic/tclProc.c b/generic/tclProc.c
index 7b0af3a..537008c 100644
--- a/generic/tclProc.c
+++ b/generic/tclProc.c
@@ -194,7 +194,7 @@ Tcl_ProcObjCmd(
     Tcl_DStringInit(&ds);
     if (nsPtr != iPtr->globalNsPtr) {
 	Tcl_DStringAppend(&ds, nsPtr->fullName, -1);
-	Tcl_DStringAppend(&ds, "::", 2);
+	TclDStringAppendLiteral(&ds, "::");
     }
     Tcl_DStringAppend(&ds, procName, -1);
 
diff --git a/generic/tclStubInit.c b/generic/tclStubInit.c
index 1b671d4..ca2638c 100644
--- a/generic/tclStubInit.c
+++ b/generic/tclStubInit.c
@@ -55,6 +55,7 @@ static int TclSockMinimumBuffersOld(int sock, int size)
 
 #ifdef __WIN32__
 #   define TclUnixWaitForFile 0
+#   define TclUnixCopyFile 0
 #   define TclpReaddir 0
 #   define TclpIsAtty 0
 #elif defined(__CYGWIN__)
@@ -498,7 +499,7 @@ static const TclIntPlatStubs tclIntPlatStubs = {
     TclpCreatePipe, /* 14 */
     TclpCreateProcess, /* 15 */
     TclpIsAtty, /* 16 */
-    0, /* 17 */
+    TclUnixCopyFile, /* 17 */
     TclpMakeFile, /* 18 */
     TclpOpenFile, /* 19 */
     TclWinAddProcess, /* 20 */
diff --git a/generic/tclTrace.c b/generic/tclTrace.c
index 25abdff..529c38a 100644
--- a/generic/tclTrace.c
+++ b/generic/tclTrace.c
@@ -1298,9 +1298,9 @@ TraceCommandProc(
 	Tcl_DStringAppendElement(&cmd, oldName);
 	Tcl_DStringAppendElement(&cmd, (newName ? newName : ""));
 	if (flags & TCL_TRACE_RENAME) {
-	    Tcl_DStringAppend(&cmd, " rename", 7);
+	    TclDStringAppendLiteral(&cmd, " rename");
 	} else if (flags & TCL_TRACE_DELETE) {
-	    Tcl_DStringAppend(&cmd, " delete", 7);
+	    TclDStringAppendLiteral(&cmd, " delete");
 	}
 
 	/*
@@ -1994,24 +1994,24 @@ TraceVarProc(
 #ifndef TCL_REMOVE_OBSOLETE_TRACES
 	    if (tvarPtr->flags & TCL_TRACE_OLD_STYLE) {
 		if (flags & TCL_TRACE_ARRAY) {
-		    Tcl_DStringAppend(&cmd, " a", 2);
+		    TclDStringAppendLiteral(&cmd, " a");
 		} else if (flags & TCL_TRACE_READS) {
-		    Tcl_DStringAppend(&cmd, " r", 2);
+		    TclDStringAppendLiteral(&cmd, " r");
 		} else if (flags & TCL_TRACE_WRITES) {
-		    Tcl_DStringAppend(&cmd, " w", 2);
+		    TclDStringAppendLiteral(&cmd, " w");
 		} else if (flags & TCL_TRACE_UNSETS) {
-		    Tcl_DStringAppend(&cmd, " u", 2);
+		    TclDStringAppendLiteral(&cmd, " u");
 		}
 	    } else {
 #endif
 		if (flags & TCL_TRACE_ARRAY) {
-		    Tcl_DStringAppend(&cmd, " array", 6);
+		    TclDStringAppendLiteral(&cmd, " array");
 		} else if (flags & TCL_TRACE_READS) {
-		    Tcl_DStringAppend(&cmd, " read", 5);
+		    TclDStringAppendLiteral(&cmd, " read");
 		} else if (flags & TCL_TRACE_WRITES) {
-		    Tcl_DStringAppend(&cmd, " write", 6);
+		    TclDStringAppendLiteral(&cmd, " write");
 		} else if (flags & TCL_TRACE_UNSETS) {
-		    Tcl_DStringAppend(&cmd, " unset", 6);
+		    TclDStringAppendLiteral(&cmd, " unset");
 		}
 #ifndef TCL_REMOVE_OBSOLETE_TRACES
 	    }
@@ -2577,7 +2577,7 @@ TclCallVarTraces(
 		    char *newPart1;
 
 		    Tcl_DStringInit(&nameCopy);
-		    Tcl_DStringAppend(&nameCopy, part1, (p-part1));
+		    Tcl_DStringAppend(&nameCopy, part1, p-part1);
 		    newPart1 = Tcl_DStringValue(&nameCopy);
 		    newPart1[offset] = 0;
 		    part1 = newPart1;
diff --git a/generic/tclUtil.c b/generic/tclUtil.c
index d5a3b94..3379f6c 100644
--- a/generic/tclUtil.c
+++ b/generic/tclUtil.c
@@ -2438,6 +2438,37 @@ Tcl_DStringAppend(
 /*
  *----------------------------------------------------------------------
  *
+ * TclDStringAppendObj, TclDStringAppendDString --
+ *
+ *	Simple wrappers round Tcl_DStringAppend that make it easier to append
+ *	from particular sources of strings.
+ *
+ *----------------------------------------------------------------------
+ */
+
+char *
+TclDStringAppendObj(
+    Tcl_DString *dsPtr,
+    Tcl_Obj *objPtr)
+{
+    int length;
+    char *bytes = Tcl_GetStringFromObj(objPtr, &length);
+
+    return Tcl_DStringAppend(dsPtr, bytes, length);
+}
+
+char *
+TclDStringAppendDString(
+    Tcl_DString *dsPtr,
+    Tcl_DString *toAppendPtr)
+{
+    return Tcl_DStringAppend(dsPtr, Tcl_DStringValue(toAppendPtr),
+	    Tcl_DStringLength(toAppendPtr));
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
  * Tcl_DStringAppendElement --
  *
  *	Append a list element to the current value of a dynamic string.
@@ -2793,9 +2824,9 @@ Tcl_DStringStartSublist(
     Tcl_DString *dsPtr)		/* Dynamic string. */
 {
     if (TclNeedSpace(dsPtr->string, dsPtr->string + dsPtr->length)) {
-	Tcl_DStringAppend(dsPtr, " {", -1);
+	TclDStringAppendLiteral(dsPtr, " {");
     } else {
-	Tcl_DStringAppend(dsPtr, "{", -1);
+	TclDStringAppendLiteral(dsPtr, "{");
     }
 }
 
@@ -2821,7 +2852,7 @@ void
 Tcl_DStringEndSublist(
     Tcl_DString *dsPtr)		/* Dynamic string. */
 {
-    Tcl_DStringAppend(dsPtr, "}", -1);
+    TclDStringAppendLiteral(dsPtr, "}");
 }
 
 /*
diff --git a/generic/tclZlib.c b/generic/tclZlib.c
index c96594d..a4ce05b 100644
--- a/generic/tclZlib.c
+++ b/generic/tclZlib.c
@@ -766,9 +766,8 @@ Tcl_ZlibStreamInit(
 	    goto error;
 	}
 	Tcl_DStringInit(&cmdname);
-	Tcl_DStringAppend(&cmdname, "::tcl::zlib::streamcmd_", -1);
-	Tcl_DStringAppend(&cmdname, Tcl_GetString(Tcl_GetObjResult(interp)),
-		-1);
+	TclDStringAppendLiteral(&cmdname, "::tcl::zlib::streamcmd_");
+	TclDStringAppendObj(&cmdname, Tcl_GetObjResult(interp));
 	if (Tcl_GetCommandInfo(interp, Tcl_DStringValue(&cmdname),
 		&cmdinfo) == 1) {
 	    Tcl_SetResult(interp,
@@ -3337,10 +3336,7 @@ ZlibTransformGetOption(
 	    Tcl_DStringAppendElement(dsPtr, Tcl_GetString(tmpObj));
 	    Tcl_DecrRefCount(tmpObj);
 	} else {
-	    int len;
-	    const char *str = Tcl_GetStringFromObj(tmpObj, &len);
-
-	    Tcl_DStringAppend(dsPtr, str, len);
+	    TclDStringAppendObj(dsPtr, tmpObj);
 	    Tcl_DecrRefCount(tmpObj);
 	    return TCL_OK;
 	}
@@ -3698,7 +3694,7 @@ ResultCopy(
 	 */
 
 	memcpy(buf, Tcl_DStringValue(&cd->decompressed), have);
-	Tcl_DStringSetLength(&cd->decompressed, 0);
+	TclDStringClear(&cd->decompressed);
 	return have;
     }
 }