Merge 8.7

24 files changed, 242 insertions, 576 deletions

diff --git a/generic/tcl.decls b/generic/tcl.decls
index 63995be..8dfc2e4 100644
--- a/generic/tcl.decls
+++ b/generic/tcl.decls
@@ -312,9 +312,10 @@ declare 79 {
 declare 80 {
     void Tcl_CancelIdleCall(Tcl_IdleProc *idleProc, void *clientData)
 }
-declare 81 {
-    int Tcl_Close(Tcl_Interp *interp, Tcl_Channel chan)
-}
+# Removed in 9.0:
+#declare 81 {
+#    int Tcl_Close(Tcl_Interp *interp, Tcl_Channel chan)
+#}
 declare 82 {
     int Tcl_CommandComplete(const char *cmd)
 }
@@ -1468,10 +1469,11 @@ declare 400 {
     Tcl_DriverBlockModeProc *Tcl_ChannelBlockModeProc(
 	    const Tcl_ChannelType *chanTypePtr)
 }
-declare 401 {
-    Tcl_DriverCloseProc *Tcl_ChannelCloseProc(
-	    const Tcl_ChannelType *chanTypePtr)
-}
+# Removed in 9.0
+#declare 401 {
+#    Tcl_DriverCloseProc *Tcl_ChannelCloseProc(
+#	    const Tcl_ChannelType *chanTypePtr)
+#}
 declare 402 {
     Tcl_DriverClose2Proc *Tcl_ChannelClose2Proc(
 	    const Tcl_ChannelType *chanTypePtr)
@@ -1484,10 +1486,11 @@ declare 404 {
     Tcl_DriverOutputProc *Tcl_ChannelOutputProc(
 	    const Tcl_ChannelType *chanTypePtr)
 }
-declare 405 {
-    Tcl_DriverSeekProc *Tcl_ChannelSeekProc(
-	    const Tcl_ChannelType *chanTypePtr)
-}
+# Removed in 9.0
+#declare 405 {
+#    Tcl_DriverSeekProc *Tcl_ChannelSeekProc(
+#	    const Tcl_ChannelType *chanTypePtr)
+#}
 declare 406 {
     Tcl_DriverSetOptionProc *Tcl_ChannelSetOptionProc(
 	    const Tcl_ChannelType *chanTypePtr)
diff --git a/generic/tcl.h b/generic/tcl.h
index 003a28d..8dbf5fe 100644
--- a/generic/tcl.h
+++ b/generic/tcl.h
@@ -1226,10 +1226,6 @@ typedef void (Tcl_ScaleTimeProc) (Tcl_Time *timebuf, void *clientData);
  * Channel version tag. This was introduced in 8.3.2/8.4.
  */
 
-#define TCL_CHANNEL_VERSION_1	((Tcl_ChannelTypeVersion) 0x1)
-#define TCL_CHANNEL_VERSION_2	((Tcl_ChannelTypeVersion) 0x2)
-#define TCL_CHANNEL_VERSION_3	((Tcl_ChannelTypeVersion) 0x3)
-#define TCL_CHANNEL_VERSION_4	((Tcl_ChannelTypeVersion) 0x4)
 #define TCL_CHANNEL_VERSION_5	((Tcl_ChannelTypeVersion) 0x5)
 
 /*
@@ -1298,7 +1294,7 @@ typedef struct Tcl_ChannelType {
 				/* Version of the channel type. */
     Tcl_DriverCloseProc *closeProc;
 				/* Function to call to close the channel, or
-				 * TCL_CLOSE2PROC if the close2Proc should be
+				 * NULL or TCL_CLOSE2PROC if the close2Proc should be
 				 * used instead. */
     Tcl_DriverInputProc *inputProc;
 				/* Function to call for input on channel. */
diff --git a/generic/tclDecls.h b/generic/tclDecls.h
index ba18baf..66ee818 100644
--- a/generic/tclDecls.h
+++ b/generic/tclDecls.h
@@ -255,8 +255,7 @@ EXTERN void		Tcl_CallWhenDeleted(Tcl_Interp *interp,
 /* 80 */
 EXTERN void		Tcl_CancelIdleCall(Tcl_IdleProc *idleProc,
 				void *clientData);
-/* 81 */
-EXTERN int		Tcl_Close(Tcl_Interp *interp, Tcl_Channel chan);
+/* Slot 81 is reserved */
 /* 82 */
 EXTERN int		Tcl_CommandComplete(const char *cmd);
 /* 83 */
@@ -1067,9 +1066,7 @@ EXTERN Tcl_ChannelTypeVersion Tcl_ChannelVersion(
 /* 400 */
 EXTERN Tcl_DriverBlockModeProc * Tcl_ChannelBlockModeProc(
 				const Tcl_ChannelType *chanTypePtr);
-/* 401 */
-EXTERN Tcl_DriverCloseProc * Tcl_ChannelCloseProc(
-				const Tcl_ChannelType *chanTypePtr);
+/* Slot 401 is reserved */
 /* 402 */
 EXTERN Tcl_DriverClose2Proc * Tcl_ChannelClose2Proc(
 				const Tcl_ChannelType *chanTypePtr);
@@ -1079,9 +1076,7 @@ EXTERN Tcl_DriverInputProc * Tcl_ChannelInputProc(
 /* 404 */
 EXTERN Tcl_DriverOutputProc * Tcl_ChannelOutputProc(
 				const Tcl_ChannelType *chanTypePtr);
-/* 405 */
-EXTERN Tcl_DriverSeekProc * Tcl_ChannelSeekProc(
-				const Tcl_ChannelType *chanTypePtr);
+/* Slot 405 is reserved */
 /* 406 */
 EXTERN Tcl_DriverSetOptionProc * Tcl_ChannelSetOptionProc(
 				const Tcl_ChannelType *chanTypePtr);
@@ -1865,7 +1860,7 @@ typedef struct TclStubs {
     int (*tcl_BadChannelOption) (Tcl_Interp *interp, const char *optionName, const char *optionList); /* 78 */
     void (*tcl_CallWhenDeleted) (Tcl_Interp *interp, Tcl_InterpDeleteProc *proc, void *clientData); /* 79 */
     void (*tcl_CancelIdleCall) (Tcl_IdleProc *idleProc, void *clientData); /* 80 */
-    int (*tcl_Close) (Tcl_Interp *interp, Tcl_Channel chan); /* 81 */
+    void (*reserved81)(void);
     int (*tcl_CommandComplete) (const char *cmd); /* 82 */
     char * (*tcl_Concat) (int argc, const char *const *argv); /* 83 */
     size_t (*tcl_ConvertElement) (const char *src, char *dst, int flags); /* 84 */
@@ -2193,11 +2188,11 @@ typedef struct TclStubs {
     const char * (*tcl_ChannelName) (const Tcl_ChannelType *chanTypePtr); /* 398 */
     Tcl_ChannelTypeVersion (*tcl_ChannelVersion) (const Tcl_ChannelType *chanTypePtr); /* 399 */
     Tcl_DriverBlockModeProc * (*tcl_ChannelBlockModeProc) (const Tcl_ChannelType *chanTypePtr); /* 400 */
-    Tcl_DriverCloseProc * (*tcl_ChannelCloseProc) (const Tcl_ChannelType *chanTypePtr); /* 401 */
+    void (*reserved401)(void);
     Tcl_DriverClose2Proc * (*tcl_ChannelClose2Proc) (const Tcl_ChannelType *chanTypePtr); /* 402 */
     Tcl_DriverInputProc * (*tcl_ChannelInputProc) (const Tcl_ChannelType *chanTypePtr); /* 403 */
     Tcl_DriverOutputProc * (*tcl_ChannelOutputProc) (const Tcl_ChannelType *chanTypePtr); /* 404 */
-    Tcl_DriverSeekProc * (*tcl_ChannelSeekProc) (const Tcl_ChannelType *chanTypePtr); /* 405 */
+    void (*reserved405)(void);
     Tcl_DriverSetOptionProc * (*tcl_ChannelSetOptionProc) (const Tcl_ChannelType *chanTypePtr); /* 406 */
     Tcl_DriverGetOptionProc * (*tcl_ChannelGetOptionProc) (const Tcl_ChannelType *chanTypePtr); /* 407 */
     Tcl_DriverWatchProc * (*tcl_ChannelWatchProc) (const Tcl_ChannelType *chanTypePtr); /* 408 */
@@ -2616,8 +2611,7 @@ extern const TclStubs *tclStubsPtr;
 	(tclStubsPtr->tcl_CallWhenDeleted) /* 79 */
 #define Tcl_CancelIdleCall \
 	(tclStubsPtr->tcl_CancelIdleCall) /* 80 */
-#define Tcl_Close \
-	(tclStubsPtr->tcl_Close) /* 81 */
+/* Slot 81 is reserved */
 #define Tcl_CommandComplete \
 	(tclStubsPtr->tcl_CommandComplete) /* 82 */
 #define Tcl_Concat \
@@ -3221,16 +3215,14 @@ extern const TclStubs *tclStubsPtr;
 	(tclStubsPtr->tcl_ChannelVersion) /* 399 */
 #define Tcl_ChannelBlockModeProc \
 	(tclStubsPtr->tcl_ChannelBlockModeProc) /* 400 */
-#define Tcl_ChannelCloseProc \
-	(tclStubsPtr->tcl_ChannelCloseProc) /* 401 */
+/* Slot 401 is reserved */
 #define Tcl_ChannelClose2Proc \
 	(tclStubsPtr->tcl_ChannelClose2Proc) /* 402 */
 #define Tcl_ChannelInputProc \
 	(tclStubsPtr->tcl_ChannelInputProc) /* 403 */
 #define Tcl_ChannelOutputProc \
 	(tclStubsPtr->tcl_ChannelOutputProc) /* 404 */
-#define Tcl_ChannelSeekProc \
-	(tclStubsPtr->tcl_ChannelSeekProc) /* 405 */
+/* Slot 405 is reserved */
 #define Tcl_ChannelSetOptionProc \
 	(tclStubsPtr->tcl_ChannelSetOptionProc) /* 406 */
 #define Tcl_ChannelGetOptionProc \
@@ -3933,4 +3925,6 @@ extern const TclStubs *tclStubsPtr;
 #   endif
 #endif
 
+#define Tcl_Close(interp, chan) Tcl_CloseEx(interp, chan, 0)
+
 #endif /* _TCLDECLS */
diff --git a/generic/tclEncoding.c b/generic/tclEncoding.c
index ff327e0..418ac0f 100644
--- a/generic/tclEncoding.c
+++ b/generic/tclEncoding.c
@@ -1638,7 +1638,7 @@ LoadEncodingFile(
 		"invalid encoding file \"%s\"", name));
 	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ENCODING", name, NULL);
     }
-    Tcl_Close(NULL, chan);
+    Tcl_CloseEx(NULL, chan, 0);
 
     return encoding;
 }
diff --git a/generic/tclIO.c b/generic/tclIO.c
index 9230fd3..fcf8085 100644
--- a/generic/tclIO.c
+++ b/generic/tclIO.c
@@ -374,11 +374,7 @@ ChanClose(
     Channel *chanPtr,
     Tcl_Interp *interp)
 {
-    if (chanPtr->typePtr->closeProc != TCL_CLOSE2PROC) {
-	return chanPtr->typePtr->closeProc(chanPtr->instanceData, interp);
-    } else {
-	return chanPtr->typePtr->close2Proc(chanPtr->instanceData, interp, 0);
-    }
+    return chanPtr->typePtr->close2Proc(chanPtr->instanceData, interp, 0);
 }
 
 static inline int
@@ -490,18 +486,13 @@ ChanSeek(
      * type and non-NULL.
      */
 
-    if (Tcl_ChannelWideSeekProc(chanPtr->typePtr) != NULL) {
-	return Tcl_ChannelWideSeekProc(chanPtr->typePtr)(chanPtr->instanceData,
-		offset, mode, errnoPtr);
-    }
-
-    if (offset<LONG_MIN || offset>LONG_MAX) {
-	*errnoPtr = EOVERFLOW;
+    if (Tcl_ChannelWideSeekProc(chanPtr->typePtr) == NULL) {
+	*errnoPtr = EINVAL;
 	return -1;
     }
 
-    return Tcl_ChannelSeekProc(chanPtr->typePtr)(chanPtr->instanceData,
-	    offset, mode, errnoPtr);
+	return Tcl_ChannelWideSeekProc(chanPtr->typePtr)(chanPtr->instanceData,
+		offset, mode, errnoPtr);
 }
 
 static inline void
@@ -677,7 +668,7 @@ TclFinalizeIOSubsystem(void)
 		 * interpreter will close the channel when it gets destroyed.
 		 */
 
-		(void) Tcl_Close(NULL, (Tcl_Channel) chanPtr);
+		(void) Tcl_CloseEx(NULL, (Tcl_Channel) chanPtr, 0);
 	    } else {
 		/*
 		 * The refcount is greater than zero, so flush the channel.
@@ -1047,7 +1038,7 @@ DeleteChannelTable(
 	statePtr->epoch++;
 	if (statePtr->refCount-- <= 1) {
 	    if (!GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
-		(void) Tcl_Close(interp, (Tcl_Channel) chanPtr);
+		(void) Tcl_CloseEx(interp, (Tcl_Channel) chanPtr, 0);
 	    }
 	}
 
@@ -1270,11 +1261,11 @@ Tcl_UnregisterChannel(
 	Tcl_Preserve(statePtr);
 	if (!GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
 	    /*
-	     * We don't want to re-enter Tcl_Close().
+	     * We don't want to re-enter Tcl_CloseEx().
 	     */
 
 	    if (!GotFlag(statePtr, CHANNEL_CLOSED)) {
-		if (Tcl_Close(interp, chan) != TCL_OK) {
+		if (Tcl_CloseEx(interp, chan, 0) != TCL_OK) {
 		    SetFlag(statePtr, CHANNEL_CLOSED);
 		    Tcl_Release(statePtr);
 		    return TCL_ERROR;
@@ -1626,8 +1617,11 @@ Tcl_CreateChannel(
 
     assert(sizeof(Tcl_ChannelTypeVersion) == sizeof(Tcl_DriverBlockModeProc *));
     assert(typePtr->typeName != NULL);
-    if (NULL == typePtr->closeProc) {
-	Tcl_Panic("channel type %s must define closeProc", typePtr->typeName);
+    if (Tcl_ChannelVersion(typePtr) != TCL_CHANNEL_VERSION_5) {
+	Tcl_Panic("channel type %s must be version TCL_CHANNEL_VERSION_5", typePtr->typeName);
+    }
+    if (typePtr->close2Proc == NULL) {
+	Tcl_Panic("channel type %s must define close2Proc", typePtr->typeName);
     }
     if ((TCL_READABLE & mask) && (NULL == typePtr->inputProc)) {
 	Tcl_Panic("channel type %s must define inputProc when used for reader channel", typePtr->typeName);
@@ -1638,9 +1632,6 @@ Tcl_CreateChannel(
     if (NULL == typePtr->watchProc) {
 	Tcl_Panic("channel type %s must define watchProc", typePtr->typeName);
     }
-    if ((NULL!=typePtr->wideSeekProc) && (NULL == typePtr->seekProc)) {
-	Tcl_Panic("channel type %s must define seekProc if defining wideSeekProc", typePtr->typeName);
-    }
 
     /*
      * JH: We could subsequently memset these to 0 to avoid the numerous
@@ -2186,7 +2177,7 @@ Tcl_UnstackChannel(
 	 */
 
 	if (statePtr->refCount + 1 <= 1) {
-	    if (Tcl_Close(interp, chan) != TCL_OK) {
+	    if (Tcl_CloseEx(interp, chan, 0) != TCL_OK) {
 		/*
 		 * TIP #219, Tcl Channel Reflection API.
 		 * "TclChanCaughtErrorBypass" is not required here, it was
@@ -3134,7 +3125,7 @@ CloseChannel(
 
 	ChannelFree(chanPtr);
 
-	return Tcl_Close(interp, (Tcl_Channel) downChanPtr);
+	return Tcl_CloseEx(interp, (Tcl_Channel) downChanPtr, 0);
     }
 
     /*
@@ -3373,7 +3364,7 @@ Tcl_SpliceChannel(
 
 	/* ARGSUSED */
 int
-Tcl_Close(
+TclClose(
     Tcl_Interp *interp,		/* Interpreter for errors. */
     Tcl_Channel chan)		/* The channel being closed. Must not be
 				 * referenced in any interpreter. */
@@ -3382,7 +3373,7 @@ Tcl_Close(
 				 * channel. */
     Channel *chanPtr;		/* The real IO channel. */
     ChannelState *statePtr;	/* State of real IO channel. */
-    int result;			/* Of calling FlushChannel. */
+    int result = 0;			/* Of calling FlushChannel. */
     int flushcode;
     int stickyError;
 
@@ -3483,12 +3474,7 @@ Tcl_Close(
      * it anymore and this will help avoid deadlocks on some channel types.
      */
 
-    if (chanPtr->typePtr->closeProc == TCL_CLOSE2PROC) {
-	result = chanPtr->typePtr->close2Proc(chanPtr->instanceData, interp,
-		TCL_CLOSE_READ);
-    } else {
-	result = 0;
-    }
+    (void)chanPtr->typePtr->close2Proc(chanPtr->instanceData, interp, TCL_CLOSE_READ);
 
     /*
      * The call to FlushChannel will flush any queued output and invoke the
@@ -3548,19 +3534,17 @@ Tcl_Close(
  *
  * Tcl_CloseEx --
  *
- *	Closes one side of a channel, read or write.
+ *	Closes one side of a channel, read or write, close all.
  *
  * Results:
  *	A standard Tcl result.
  *
  * Side effects:
- *	Closes one direction of the channel.
+ *	Closes one direction of the channel, or do a full close.
  *
  * NOTE:
  *	Tcl_CloseEx closes the specified direction of the channel as far as
- *	the user is concerned. The channel keeps existing however. You cannot
- *	calls this function to close the last possible direction of the
- *	channel. Use Tcl_Close for that.
+ *	the user is concerned. If flags = 0, this is equivalent to Tcl_Close.
  *
  *----------------------------------------------------------------------
  */
@@ -3580,18 +3564,26 @@ Tcl_CloseEx(
 	return TCL_OK;
     }
 
-    /* TODO: assert flags validity ? */
-
     chanPtr = (Channel *) chan;
     statePtr = chanPtr->state;
 
+    if ((flags & (TCL_READABLE | TCL_WRITABLE)) == 0) {
+	return TclClose(interp, chan);
+    }
+    if ((flags & (TCL_READABLE | TCL_WRITABLE)) == (TCL_READABLE | TCL_WRITABLE)) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"double-close of channels not supported by %ss",
+		chanPtr->typePtr->typeName));
+	return TCL_ERROR;
+    }
+
     /*
      * Does the channel support half-close anyway? Error if not.
      */
 
     if (!chanPtr->typePtr->close2Proc) {
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
-                "half-close of channels not supported by %ss",
+		"half-close of channels not supported by %ss",
 		chanPtr->typePtr->typeName));
 	return TCL_ERROR;
     }
@@ -4214,12 +4206,12 @@ WillWrite(
 {
     int inputBuffered;
 
-    if ((Tcl_ChannelSeekProc(chanPtr->typePtr) != NULL) &&
-            ((inputBuffered = Tcl_InputBuffered((Tcl_Channel) chanPtr)) > 0)){
-        int ignore;
+    if (((Tcl_ChannelWideSeekProc(chanPtr->typePtr) != NULL)
+	    ) && ((inputBuffered = Tcl_InputBuffered((Tcl_Channel) chanPtr)) > 0)){
+	int ignore;
 
-        DiscardInputQueued(chanPtr->state, 0);
-        ChanSeek(chanPtr, -inputBuffered, SEEK_CUR, &ignore);
+	DiscardInputQueued(chanPtr->state, 0);
+	ChanSeek(chanPtr, -inputBuffered, SEEK_CUR, &ignore);
     }
 }
 
@@ -4236,8 +4228,8 @@ WillRead(
 	Tcl_SetErrno(EINVAL);
 	return -1;
     }
-    if ((Tcl_ChannelSeekProc(chanPtr->typePtr) != NULL)
-            && (Tcl_OutputBuffered((Tcl_Channel) chanPtr) > 0)) {
+    if (((Tcl_ChannelWideSeekProc(chanPtr->typePtr) != NULL)
+	    ) && (Tcl_OutputBuffered((Tcl_Channel) chanPtr) > 0)) {
 	/*
 	 * CAVEAT - The assumption here is that FlushChannel() will push out
 	 * the bytes of any writes that are in progress.  Since this is a
@@ -7000,7 +6992,8 @@ Tcl_Seek(
      * defined. This means that the channel does not support seeking.
      */
 
-    if (Tcl_ChannelSeekProc(chanPtr->typePtr) == NULL) {
+    if ((Tcl_ChannelWideSeekProc(chanPtr->typePtr) == NULL)
+    ) {
 	Tcl_SetErrno(EINVAL);
 	return -1;
     }
@@ -7164,7 +7157,8 @@ Tcl_Tell(
      * defined. This means that the channel does not support seeking.
      */
 
-    if (Tcl_ChannelSeekProc(chanPtr->typePtr) == NULL) {
+    if ((Tcl_ChannelWideSeekProc(chanPtr->typePtr) == NULL)
+    ) {
 	Tcl_SetErrno(EINVAL);
 	return -1;
     }
@@ -10488,14 +10482,6 @@ Tcl_ChannelVersion(
     const Tcl_ChannelType *chanTypePtr)
 				/* Pointer to channel type. */
 {
-    if ((chanTypePtr->version < TCL_CHANNEL_VERSION_2)
-	    || (chanTypePtr->version > TCL_CHANNEL_VERSION_5)) {
-	/*
-	 * In <v2 channel versions, the version field is occupied by the
-	 * Tcl_DriverBlockModeProc
-	 */
-	return TCL_CHANNEL_VERSION_1;
-    }
     return chanTypePtr->version;
 }
 
@@ -10519,43 +10505,12 @@ Tcl_ChannelBlockModeProc(
     const Tcl_ChannelType *chanTypePtr)
 				/* Pointer to channel type. */
 {
-    if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_2) {
-	/*
-	 * The v1 structure had the blockModeProc in a different place.
-	 */
-	return (Tcl_DriverBlockModeProc *) chanTypePtr->version;
-    }
-
     return chanTypePtr->blockModeProc;
 }
 
 /*
  *----------------------------------------------------------------------
  *
- * Tcl_ChannelCloseProc --
- *
- *	Return the Tcl_DriverCloseProc of the channel type.
- *
- * Results:
- *	A pointer to the proc.
- *
- * Side effects:
- *	None.
- *
- *----------------------------------------------------------------------
- */
-
-Tcl_DriverCloseProc *
-Tcl_ChannelCloseProc(
-    const Tcl_ChannelType *chanTypePtr)
-				/* Pointer to channel type. */
-{
-    return chanTypePtr->closeProc;
-}
-
-/*
- *----------------------------------------------------------------------
- *
  * Tcl_ChannelClose2Proc --
  *
  *	Return the Tcl_DriverClose2Proc of the channel type.
@@ -10628,30 +10583,6 @@ Tcl_ChannelOutputProc(
 /*
  *----------------------------------------------------------------------
  *
- * Tcl_ChannelSeekProc --
- *
- *	Return the Tcl_DriverSeekProc of the channel type.
- *
- * Results:
- *	A pointer to the proc.
- *
- * Side effects:
- *	None.
- *
- *----------------------------------------------------------------------
- */
-
-Tcl_DriverSeekProc *
-Tcl_ChannelSeekProc(
-    const Tcl_ChannelType *chanTypePtr)
-				/* Pointer to channel type. */
-{
-    return chanTypePtr->seekProc;
-}
-
-/*
- *----------------------------------------------------------------------
- *
  * Tcl_ChannelSetOptionProc --
  *
  *	Return the Tcl_DriverSetOptionProc of the channel type.
@@ -10766,9 +10697,6 @@ Tcl_ChannelFlushProc(
     const Tcl_ChannelType *chanTypePtr)
 				/* Pointer to channel type. */
 {
-    if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_2) {
-	return NULL;
-    }
     return chanTypePtr->flushProc;
 }
 
@@ -10793,9 +10721,6 @@ Tcl_ChannelHandlerProc(
     const Tcl_ChannelType *chanTypePtr)
 				/* Pointer to channel type. */
 {
-    if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_2) {
-	return NULL;
-    }
     return chanTypePtr->handlerProc;
 }
 
@@ -10820,9 +10745,6 @@ Tcl_ChannelWideSeekProc(
     const Tcl_ChannelType *chanTypePtr)
 				/* Pointer to channel type. */
 {
-    if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_3) {
-	return NULL;
-    }
     return chanTypePtr->wideSeekProc;
 }
 
@@ -10848,9 +10770,6 @@ Tcl_ChannelThreadActionProc(
     const Tcl_ChannelType *chanTypePtr)
 				/* Pointer to channel type. */
 {
-    if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_4) {
-	return NULL;
-    }
     return chanTypePtr->threadActionProc;
 }
 
diff --git a/generic/tclIOCmd.c b/generic/tclIOCmd.c
index 2e492b8..e10be42 100644
--- a/generic/tclIOCmd.c
+++ b/generic/tclIOCmd.c
@@ -967,7 +967,7 @@ Tcl_ExecObjCmd(
 	 */
 
 	TclGetAndDetachPids(interp, chan);
-	if (Tcl_Close(interp, chan) != TCL_OK) {
+	if (Tcl_CloseEx(interp, chan, 0) != TCL_OK) {
 	    return TCL_ERROR;
 	}
 	return TCL_OK;
@@ -999,7 +999,7 @@ Tcl_ExecObjCmd(
      * string.
      */
 
-    result = Tcl_Close(interp, chan);
+    result = Tcl_CloseEx(interp, chan, 0);
     Tcl_AppendObjToObj(resultPtr, Tcl_GetObjResult(interp));
 
     /*
@@ -1405,7 +1405,7 @@ AcceptCallbackProc(
 	 * the client socket - just close it.
 	 */
 
-	Tcl_Close(NULL, chan);
+	Tcl_CloseEx(NULL, chan, 0);
     }
 }
 
diff --git a/generic/tclIOGT.c b/generic/tclIOGT.c
index 5f0f55e..e9c4fae 100644
--- a/generic/tclIOGT.c
+++ b/generic/tclIOGT.c
@@ -22,13 +22,11 @@
 static int		TransformBlockModeProc(ClientData instanceData,
 			    int mode);
 static int		TransformCloseProc(ClientData instanceData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static int		TransformInputProc(ClientData instanceData, char *buf,
 			    int toRead, int *errorCodePtr);
 static int		TransformOutputProc(ClientData instanceData,
 			    const char *buf, int toWrite, int *errorCodePtr);
-static int		TransformSeekProc(ClientData instanceData, long offset,
-			    int mode, int *errorCodePtr);
 static int		TransformSetOptionProc(ClientData instanceData,
 			    Tcl_Interp *interp, const char *optionName,
 			    const char *value);
@@ -119,15 +117,15 @@ static inline void	ResultAdd(ResultBuffer *r, unsigned char *buf,
 static const Tcl_ChannelType transformChannelType = {
     "transform",		/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    TransformCloseProc,		/* Close proc. */
+    NULL,		/* Close proc. */
     TransformInputProc,		/* Input proc. */
     TransformOutputProc,	/* Output proc. */
-    TransformSeekProc,		/* Seek proc. */
+    NULL,			/* Seek proc. */
     TransformSetOptionProc,	/* Set option proc. */
     TransformGetOptionProc,	/* Get option proc. */
     TransformWatchProc,		/* Initialize notifier. */
     TransformGetFileHandleProc,	/* Get OS handles out of channel. */
-    NULL,			/* close2proc */
+    TransformCloseProc,		/* close2proc */
     TransformBlockModeProc,	/* Set blocking/nonblocking mode.*/
     NULL,			/* Flush proc. */
     TransformNotifyProc,	/* Handling of events bubbling up. */
@@ -533,10 +531,15 @@ TransformBlockModeProc(
 static int
 TransformCloseProc(
     ClientData instanceData,
-    Tcl_Interp *interp)
+    Tcl_Interp *interp,
+	int flags)
 {
     TransformChannelData *dataPtr = (TransformChannelData *)instanceData;
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
     /*
      * Important: In this procedure 'dataPtr->self' already points to the
      * underlying channel.
@@ -811,73 +814,6 @@ TransformOutputProc(
 /*
  *----------------------------------------------------------------------
  *
- * TransformSeekProc --
- *
- *	This procedure is called by the generic IO level to move the access
- *	point in a channel.
- *
- * Side effects:
- *	Moves the location at which the channel will be accessed in future
- *	operations. Flushes all transformation buffers, then forwards it to
- *	the underlying channel.
- *
- * Result:
- *	-1 if failed, the new position if successful. An output argument
- *	contains the POSIX error code if an error occurred, or zero.
- *
- *----------------------------------------------------------------------
- */
-
-static int
-TransformSeekProc(
-    ClientData instanceData,	/* The channel to manipulate. */
-    long offset,		/* Size of movement. */
-    int mode,			/* How to move. */
-    int *errorCodePtr)		/* Location of error flag. */
-{
-    TransformChannelData *dataPtr = (TransformChannelData *)instanceData;
-    Tcl_Channel parent = Tcl_GetStackedChannel(dataPtr->self);
-    const Tcl_ChannelType *parentType = Tcl_GetChannelType(parent);
-    Tcl_DriverSeekProc *parentSeekProc = Tcl_ChannelSeekProc(parentType);
-
-    if ((offset == 0) && (mode == SEEK_CUR)) {
-	/*
-	 * This is no seek but a request to tell the caller the current
-	 * location. Simply pass the request down.
-	 */
-
-	return parentSeekProc(Tcl_GetChannelInstanceData(parent), offset,
-		mode, errorCodePtr);
-    }
-
-    /*
-     * It is a real request to change the position. Flush all data waiting for
-     * output and discard everything in the input buffers. Then pass the
-     * request down, unchanged.
-     */
-
-    PreserveData(dataPtr);
-    if (dataPtr->mode & TCL_WRITABLE) {
-	ExecuteCallback(dataPtr, NULL, A_FLUSH_WRITE, NULL, 0, TRANSMIT_DOWN,
-		P_NO_PRESERVE);
-    }
-
-    if (dataPtr->mode & TCL_READABLE) {
-	ExecuteCallback(dataPtr, NULL, A_CLEAR_READ, NULL, 0, TRANSMIT_DONT,
-		P_NO_PRESERVE);
-	ResultClear(&dataPtr->result);
-	dataPtr->readIsFlushed = 0;
-	dataPtr->eofPending = 0;
-    }
-    ReleaseData(dataPtr);
-
-    return parentSeekProc(Tcl_GetChannelInstanceData(parent), offset, mode,
-	    errorCodePtr);
-}
-
-/*
- *----------------------------------------------------------------------
- *
  * TransformWideSeekProc --
  *
  *	This procedure is called by the generic IO level to move the access
@@ -905,7 +841,6 @@ TransformWideSeekProc(
     TransformChannelData *dataPtr = (TransformChannelData *)instanceData;
     Tcl_Channel parent = Tcl_GetStackedChannel(dataPtr->self);
     const Tcl_ChannelType *parentType	= Tcl_GetChannelType(parent);
-    Tcl_DriverSeekProc *parentSeekProc = Tcl_ChannelSeekProc(parentType);
     Tcl_DriverWideSeekProc *parentWideSeekProc =
 	    Tcl_ChannelWideSeekProc(parentType);
     ClientData parentData = Tcl_GetChannelInstanceData(parent);
@@ -918,9 +853,10 @@ TransformWideSeekProc(
 
 	if (parentWideSeekProc != NULL) {
 	    return parentWideSeekProc(parentData, offset, mode, errorCodePtr);
+	} else {
+	    *errorCodePtr = EINVAL;
+	    return -1;
 	}
-
-	return parentSeekProc(parentData, 0, mode, errorCodePtr);
     }
 
     /*
@@ -948,25 +884,11 @@ TransformWideSeekProc(
      * If we have a wide seek capability, we should stick with that.
      */
 
-    if (parentWideSeekProc != NULL) {
-	return parentWideSeekProc(parentData, offset, mode, errorCodePtr);
-    }
-
-    /*
-     * We're transferring to narrow seeks at this point; this is a bit complex
-     * because we have to check whether the seek is possible first (i.e.
-     * whether we are losing information in truncating the bits of the
-     * offset). Luckily, there's a defined error for what happens when trying
-     * to go out of the representable range.
-     */
-
-    if (offset<LONG_MIN || offset>LONG_MAX) {
-	*errorCodePtr = EOVERFLOW;
+    if (parentWideSeekProc == NULL) {
+	*errorCodePtr = EINVAL;
 	return -1;
     }
-
-    return parentSeekProc(parentData, offset,
-	    mode, errorCodePtr);
+	return parentWideSeekProc(parentData, offset, mode, errorCodePtr);
 }
 
 /*
diff --git a/generic/tclIORChan.c b/generic/tclIORChan.c
index a460090..018c59f 100644
--- a/generic/tclIORChan.c
+++ b/generic/tclIORChan.c
@@ -32,7 +32,7 @@
  */
 
 static int		ReflectClose(ClientData clientData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static int		ReflectInput(ClientData clientData, char *buf,
 			    int toRead, int *errorCodePtr);
 static int		ReflectOutput(ClientData clientData, const char *buf,
@@ -46,8 +46,6 @@ static int		ReflectEventDelete(Tcl_Event *ev, ClientData cd);
 #endif
 static Tcl_WideInt	ReflectSeekWide(ClientData clientData,
 			    Tcl_WideInt offset, int mode, int *errorCodePtr);
-static int		ReflectSeek(ClientData clientData, long offset,
-			    int mode, int *errorCodePtr);
 static int		ReflectGetOption(ClientData clientData,
 			    Tcl_Interp *interp, const char *optionName,
 			    Tcl_DString *dsPtr);
@@ -65,15 +63,15 @@ static void     TimerRunWrite(ClientData clientData);
 static const Tcl_ChannelType tclRChannelType = {
     "tclrchannel",	   /* Type name.				  */
     TCL_CHANNEL_VERSION_5, /* v5 channel */
-    ReflectClose,	   /* Close channel, clean instance data	  */
+    NULL,	   /* Close channel, clean instance data	  */
     ReflectInput,	   /* Handle read request			  */
     ReflectOutput,	   /* Handle write request			  */
-    ReflectSeek,	   /* Move location of access point.	NULL'able */
+    NULL,
     ReflectSetOption,	   /* Set options.			NULL'able */
     ReflectGetOption,	   /* Get options.			NULL'able */
     ReflectWatch,	   /* Initialize notifier			  */
     NULL,		   /* Get OS handle from the channel.	NULL'able */
-    NULL,		   /* No close2 support.		NULL'able */
+	ReflectClose,	   /* No close2 support.		NULL'able */
     ReflectBlock,	   /* Set blocking/nonblocking.		NULL'able */
     NULL,		   /* Flush channel. Not used by core.	NULL'able */
     NULL,		   /* Handle events.			NULL'able */
@@ -81,7 +79,7 @@ static const Tcl_ChannelType tclRChannelType = {
 #if TCL_THREADS
     ReflectThread,         /* thread action, tracking owner */
 #else
-    NULL,		   /* thread action */
+	(void *)-1,		   /* thread action */
 #endif
     NULL		   /* truncate */
 };
@@ -697,7 +695,6 @@ TclChanCreateObjCmd(
 	    clonePtr->blockModeProc = NULL;
 	}
 	if (!(methods & FLAG(METH_SEEK))) {
-	    clonePtr->seekProc = NULL;
 	    clonePtr->wideSeekProc = NULL;
 	}
 
@@ -1153,7 +1150,8 @@ TclChanCaughtErrorBypass(
 static int
 ReflectClose(
     ClientData clientData,
-    Tcl_Interp *interp)
+    Tcl_Interp *interp,
+	int flags)
 {
     ReflectedChannel *rcPtr = (ReflectedChannel *)clientData;
     int result;			/* Result code for 'close' */
@@ -1163,6 +1161,10 @@ ReflectClose(
     Tcl_HashEntry *hPtr;	/* Entry in the above map */
     const Tcl_ChannelType *tctPtr;
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
     if (TclInThreadExit()) {
 	/*
 	 * This call comes from TclFinalizeIOSystem. There are no
@@ -1616,24 +1618,6 @@ ReflectSeekWide(
     newLoc = -1;
     goto stop;
 }
-
-static int
-ReflectSeek(
-    ClientData clientData,
-    long offset,
-    int seekMode,
-    int *errorCodePtr)
-{
-    /*
-     * This function can be invoked from a transformation which is based on
-     * standard seeking, i.e. non-wide. Because of this we have to implement
-     * it, a dummy is not enough. We simply delegate the call to the wide
-     * routine.
-     */
-
-    return ReflectSeekWide(clientData, offset, seekMode,
-	    errorCodePtr);
-}
 
 /*
  *----------------------------------------------------------------------
diff --git a/generic/tclIORTrans.c b/generic/tclIORTrans.c
index 0a68518..9e18a05 100644
--- a/generic/tclIORTrans.c
+++ b/generic/tclIORTrans.c
@@ -32,7 +32,7 @@
  */
 
 static int		ReflectClose(ClientData clientData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static int		ReflectInput(ClientData clientData, char *buf,
 			    int toRead, int *errorCodePtr);
 static int		ReflectOutput(ClientData clientData, const char *buf,
@@ -41,8 +41,6 @@ static void		ReflectWatch(ClientData clientData, int mask);
 static int		ReflectBlock(ClientData clientData, int mode);
 static Tcl_WideInt	ReflectSeekWide(ClientData clientData,
 			    Tcl_WideInt offset, int mode, int *errorCodePtr);
-static int		ReflectSeek(ClientData clientData, long offset,
-			    int mode, int *errorCodePtr);
 static int		ReflectGetOption(ClientData clientData,
 			    Tcl_Interp *interp, const char *optionName,
 			    Tcl_DString *dsPtr);
@@ -60,15 +58,15 @@ static int		ReflectNotify(ClientData clientData, int mask);
 static const Tcl_ChannelType tclRTransformType = {
     "tclrtransform",		/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel. */
-    ReflectClose,		/* Close channel, clean instance data. */
+    NULL,		/* Close channel, clean instance data. */
     ReflectInput,		/* Handle read request. */
     ReflectOutput,		/* Handle write request. */
-    ReflectSeek,		/* Move location of access point. */
+	NULL,			/* Move location of access point. */
     ReflectSetOption,		/* Set options. */
     ReflectGetOption,		/* Get options. */
     ReflectWatch,		/* Initialize notifier. */
     ReflectHandle,		/* Get OS handle from the channel. */
-    NULL,			/* No close2 support. NULL'able. */
+	ReflectClose,		/* No close2 support. NULL'able. */
     ReflectBlock,		/* Set blocking/nonblocking. */
     NULL,			/* Flush channel. Not used by core.
 				 * NULL'able. */
@@ -881,7 +879,8 @@ UnmarshallErrorResult(
 static int
 ReflectClose(
     ClientData clientData,
-    Tcl_Interp *interp)
+    Tcl_Interp *interp,
+    int flags)
 {
     ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
     int errorCode, errorCodeSet = 0;
@@ -892,6 +891,10 @@ ReflectClose(
 				 * in this interp. */
     Tcl_HashEntry *hPtr;	/* Entry in the above map */
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
     if (TclInThreadExit()) {
 	/*
 	 * This call comes from TclFinalizeIOSystem. There are no
@@ -1329,18 +1332,6 @@ ReflectSeekWide(
     Channel *parent = (Channel *) rtPtr->parent;
     Tcl_WideInt curPos;		/* Position on the device. */
 
-    Tcl_DriverSeekProc *seekProc =
-	    Tcl_ChannelSeekProc(Tcl_GetChannelType(rtPtr->parent));
-
-    /*
-     * Fail if the parent channel is not seekable.
-     */
-
-    if (seekProc == NULL) {
-	Tcl_SetErrno(EINVAL);
-	return -1;
-    }
-
     /*
      * Check if we can leave out involving the Tcl level, i.e. transformation
      * handler. This is true for tell requests, and transformations which
@@ -1384,16 +1375,12 @@ ReflectSeekWide(
      * non-NULL...
      */
 
-    if (Tcl_ChannelWideSeekProc(parent->typePtr) != NULL) {
-	curPos = Tcl_ChannelWideSeekProc(parent->typePtr)(parent->instanceData, offset,
-		seekMode, errorCodePtr);
-    } else if (offset < LONG_MIN || offset > LONG_MAX) {
-	*errorCodePtr = EOVERFLOW;
+    if (Tcl_ChannelWideSeekProc(parent->typePtr) == NULL) {
+	*errorCodePtr = EINVAL;
 	curPos = -1;
     } else {
-	curPos = Tcl_ChannelSeekProc(parent->typePtr)(
-		parent->instanceData, offset, seekMode,
-		errorCodePtr);
+    	curPos = Tcl_ChannelWideSeekProc(parent->typePtr)(parent->instanceData, offset,
+    		seekMode, errorCodePtr);
     }
     if (curPos == -1) {
 	Tcl_SetErrno(*errorCodePtr);
@@ -1403,24 +1390,6 @@ ReflectSeekWide(
     Tcl_Release(rtPtr);
     return curPos;
 }
-
-static int
-ReflectSeek(
-    ClientData clientData,
-    long offset,
-    int seekMode,
-    int *errorCodePtr)
-{
-    /*
-     * This function can be invoked from a transformation which is based on
-     * standard seeking, i.e. non-wide. Because of this we have to implement
-     * it, a dummy is not enough. We simply delegate the call to the wide
-     * routine.
-     */
-
-    return ReflectSeekWide(clientData, offset, seekMode,
-	    errorCodePtr);
-}
 
 /*
  *----------------------------------------------------------------------
diff --git a/generic/tclIOUtil.c b/generic/tclIOUtil.c
index 5c0ce0b..26ff1d8 100644
--- a/generic/tclIOUtil.c
+++ b/generic/tclIOUtil.c
@@ -1733,7 +1733,7 @@ Tcl_FSEvalFileEx(
     if (encodingName != NULL) {
 	if (Tcl_SetChannelOption(interp, chan, "-encoding", encodingName)
 		!= TCL_OK) {
-	    Tcl_Close(interp,chan);
+	    Tcl_CloseEx(interp,chan,0);
 	    return result;
 	}
     }
@@ -1746,7 +1746,7 @@ Tcl_FSEvalFileEx(
      */
 
     if (Tcl_ReadChars(chan, objPtr, 1, 0) == TCL_IO_FAILURE) {
-	Tcl_Close(interp, chan);
+	Tcl_CloseEx(interp, chan, 0);
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		"couldn't read file \"%s\": %s",
 		TclGetString(pathPtr), Tcl_PosixError(interp)));
@@ -1761,14 +1761,14 @@ Tcl_FSEvalFileEx(
 
     if (Tcl_ReadChars(chan, objPtr, -1,
 	    memcmp(string, "\xef\xbb\xbf", 3)) == TCL_IO_FAILURE) {
-	Tcl_Close(interp, chan);
+	Tcl_CloseEx(interp, chan, 0);
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		"couldn't read file \"%s\": %s",
 		TclGetString(pathPtr), Tcl_PosixError(interp)));
 	goto end;
     }
 
-    if (Tcl_Close(interp, chan) != TCL_OK) {
+    if (Tcl_CloseEx(interp, chan, 0) != TCL_OK) {
 	goto end;
     }
 
@@ -1869,7 +1869,7 @@ TclNREvalFile(
     if (encodingName != NULL) {
 	if (Tcl_SetChannelOption(interp, chan, "-encoding", encodingName)
 		!= TCL_OK) {
-	    Tcl_Close(interp,chan);
+	    Tcl_CloseEx(interp, chan, 0);
 	    return TCL_ERROR;
 	}
     }
@@ -1882,7 +1882,7 @@ TclNREvalFile(
      */
 
     if (Tcl_ReadChars(chan, objPtr, 1, 0) == TCL_IO_FAILURE) {
-	Tcl_Close(interp, chan);
+	Tcl_CloseEx(interp, chan, 0);
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		"couldn't read file \"%s\": %s",
 		TclGetString(pathPtr), Tcl_PosixError(interp)));
@@ -1898,7 +1898,7 @@ TclNREvalFile(
 
     if (Tcl_ReadChars(chan, objPtr, -1,
 	    memcmp(string, "\xef\xbb\xbf", 3)) == TCL_IO_FAILURE) {
-	Tcl_Close(interp, chan);
+	Tcl_CloseEx(interp, chan, 0);
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		"couldn't read file \"%s\": %s",
 		TclGetString(pathPtr), Tcl_PosixError(interp)));
@@ -1906,7 +1906,7 @@ TclNREvalFile(
 	return TCL_ERROR;
     }
 
-    if (Tcl_Close(interp, chan) != TCL_OK) {
+    if (Tcl_CloseEx(interp, chan, 0) != TCL_OK) {
 	Tcl_DecrRefCount(objPtr);
 	return TCL_ERROR;
     }
@@ -2238,7 +2238,7 @@ Tcl_FSOpenFileChannel(
 			"could not seek to end of file while opening \"%s\": %s",
 			TclGetString(pathPtr), Tcl_PosixError(interp)));
 	    }
-	    Tcl_Close(NULL, retVal);
+	    Tcl_CloseEx(NULL, retVal, 0);
 	    return NULL;
 	}
 	if (binary) {
@@ -3248,11 +3248,11 @@ Tcl_LoadFile(
 	}
 	buffer = TclpLoadMemoryGetBuffer(interp, size);
 	if (!buffer) {
-	    Tcl_Close(interp, data);
+	    Tcl_CloseEx(interp, data, 0);
 	    goto mustCopyToTempAnyway;
 	}
 	ret = Tcl_Read(data, (char *)buffer, size);
-	Tcl_Close(interp, data);
+	Tcl_CloseEx(interp, data, 0);
 	ret = TclpLoadMemory(interp, buffer, size, ret, handlePtr,
 		&unloadProcPtr, flags);
 	if (ret == TCL_OK && *handlePtr != NULL) {
@@ -4251,7 +4251,7 @@ TclCrossFilesystemCopy(
 	 * Could not open an input channel.  Why didn't the caller check this?
 	 */
 
-	Tcl_Close(interp, out);
+	Tcl_CloseEx(interp, out, 0);
 	goto done;
     }
 
@@ -4268,8 +4268,8 @@ TclCrossFilesystemCopy(
      * If the copy failed, assume that copy channel left an error message.
      */
 
-    Tcl_Close(interp, in);
-    Tcl_Close(interp, out);
+    Tcl_CloseEx(interp, in, 0);
+    Tcl_CloseEx(interp, out, 0);
 
     /*
      * Set modification date of copied file.
diff --git a/generic/tclInt.h b/generic/tclInt.h
index 4eb929a..15f6b54 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -4099,7 +4099,7 @@ MODULE_SCOPE void	TclProcessCreated(Tcl_Pid pid);
 MODULE_SCOPE TclProcessWaitStatus TclProcessWait(Tcl_Pid pid, int options,
 			    int *codePtr, Tcl_Obj **msgObjPtr,
 			    Tcl_Obj **errorObjPtr);
-
+MODULE_SCOPE int TclClose(Tcl_Interp *,	Tcl_Channel chan);
 /*
  * TIP #508: [array default]
  */
diff --git a/generic/tclMain.c b/generic/tclMain.c
index 16e2159..8b8daf3 100644
--- a/generic/tclMain.c
+++ b/generic/tclMain.c
@@ -250,7 +250,7 @@ Tcl_SourceRCFile(
 
 	    c = Tcl_OpenFileChannel(NULL, fullName, "r", 0);
 	    if (c != NULL) {
-		Tcl_Close(NULL, c);
+		Tcl_CloseEx(NULL, c, 0);
 		if (Tcl_EvalFile(interp, fullName) != TCL_OK) {
 		    chan = Tcl_GetStdChannel(TCL_STDERR);
 		    if (chan) {
diff --git a/generic/tclPipe.c b/generic/tclPipe.c
index 6c73f92..61a2080 100644
--- a/generic/tclPipe.c
+++ b/generic/tclPipe.c
@@ -351,7 +351,7 @@ TclCleanupChildren(
 		Tcl_DecrRefCount(objPtr);
 	    }
 	}
-	Tcl_Close(NULL, errorChan);
+	Tcl_CloseEx(NULL, errorChan, 0);
     }
 
     /*
diff --git a/generic/tclStubInit.c b/generic/tclStubInit.c
index 48ff391..753b604 100644
--- a/generic/tclStubInit.c
+++ b/generic/tclStubInit.c
@@ -834,7 +834,7 @@ const TclStubs tclStubs = {
     Tcl_BadChannelOption, /* 78 */
     Tcl_CallWhenDeleted, /* 79 */
     Tcl_CancelIdleCall, /* 80 */
-    Tcl_Close, /* 81 */
+    0, /* 81 */
     Tcl_CommandComplete, /* 82 */
     Tcl_Concat, /* 83 */
     Tcl_ConvertElement, /* 84 */
@@ -1162,11 +1162,11 @@ const TclStubs tclStubs = {
     Tcl_ChannelName, /* 398 */
     Tcl_ChannelVersion, /* 399 */
     Tcl_ChannelBlockModeProc, /* 400 */
-    Tcl_ChannelCloseProc, /* 401 */
+    0, /* 401 */
     Tcl_ChannelClose2Proc, /* 402 */
     Tcl_ChannelInputProc, /* 403 */
     Tcl_ChannelOutputProc, /* 404 */
-    Tcl_ChannelSeekProc, /* 405 */
+    0, /* 405 */
     Tcl_ChannelSetOptionProc, /* 406 */
     Tcl_ChannelGetOptionProc, /* 407 */
     Tcl_ChannelWatchProc, /* 408 */
diff --git a/generic/tclZipfs.c b/generic/tclZipfs.c
index fbbe1ed..afba76b 100644
--- a/generic/tclZipfs.c
+++ b/generic/tclZipfs.c
@@ -385,13 +385,11 @@ static int		ZipFSLoadFile(Tcl_Interp *interp, Tcl_Obj *path,
 static void		ZipfsExitHandler(ClientData clientData);
 static void		ZipfsSetup(void);
 static int		ZipChannelClose(void *instanceData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static int		ZipChannelGetFile(void *instanceData,
 			    int direction, void **handlePtr);
 static int		ZipChannelRead(void *instanceData, char *buf,
 			    int toRead, int *errloc);
-static int		ZipChannelSeek(void *instanceData, long offset,
-			    int mode, int *errloc);
 static Tcl_WideInt ZipChannelWideSeek(void *instanceData, Tcl_WideInt offset,
 			    int mode, int *errloc);
 static void		ZipChannelWatchChannel(void *instanceData,
@@ -444,15 +442,15 @@ static const Tcl_Filesystem zipfsFilesystem = {
 static Tcl_ChannelType ZipChannelType = {
     "zip",		    /* Type name. */
     TCL_CHANNEL_VERSION_5,
-    ZipChannelClose,	    /* Close channel, clean instance data */
+    NULL,	    /* Close channel, clean instance data */
     ZipChannelRead,	    /* Handle read request */
     ZipChannelWrite,	    /* Handle write request */
-    ZipChannelSeek,	    /* Move location of access point, NULL'able */
+	NULL,	    /* Move location of access point, NULL'able */
     NULL,		    /* Set options, NULL'able */
     NULL,		    /* Get options, NULL'able */
     ZipChannelWatchChannel, /* Initialize notifier */
     ZipChannelGetFile,	    /* Get OS handle from the channel */
-    NULL,		    /* 2nd version of close channel, NULL'able */
+	ZipChannelClose,	    /* 2nd version of close channel, NULL'able */
     NULL,		    /* Set blocking mode for raw channel, NULL'able */
     NULL,		    /* Function to flush channel, NULL'able */
     NULL,		    /* Function to handle event, NULL'able */
@@ -938,7 +936,7 @@ ZipFSCloseArchive(
 	zf->ptrToFree = NULL;
     }
     if (zf->chan) {
-	Tcl_Close(interp, zf->chan);
+	Tcl_CloseEx(interp, zf->chan, 0);
 	zf->chan = NULL;
     }
 }
@@ -1141,7 +1139,7 @@ ZipFSOpenArchive(
 	    ZIPFS_POSIX_ERROR(interp, "file read error");
 	    goto error;
 	}
-	Tcl_Close(interp, zf->chan);
+	Tcl_CloseEx(interp, zf->chan, 0);
 	zf->chan = NULL;
     } else {
 #ifdef _WIN32
@@ -2139,11 +2137,11 @@ ZipAddFile(
 #ifdef _WIN32
 	/* hopefully a directory */
 	if (strcmp("permission denied", Tcl_PosixError(interp)) == 0) {
-	    Tcl_Close(interp, in);
+	    Tcl_CloseEx(interp, in, 0);
 	    return TCL_OK;
 	}
 #endif /* _WIN32 */
-	Tcl_Close(interp, in);
+	Tcl_CloseEx(interp, in, 0);
 	return TCL_ERROR;
     } else {
 	Tcl_Obj *pathObj = Tcl_NewStringObj(path, -1);
@@ -2162,12 +2160,12 @@ ZipAddFile(
 	len = Tcl_Read(in, buf, bufsize);
 	if (len == TCL_IO_FAILURE) {
 	    if (nbyte == 0 && errno == EISDIR) {
-		Tcl_Close(interp, in);
+		Tcl_CloseEx(interp, in, 0);
 		return TCL_OK;
 	    }
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf("read error on \"%s\": %s",
 		    path, Tcl_PosixError(interp)));
-	    Tcl_Close(interp, in);
+	    Tcl_CloseEx(interp, in, 0);
 	    return TCL_ERROR;
 	}
 	if (len == 0) {
@@ -2179,7 +2177,7 @@ ZipAddFile(
     if (Tcl_Seek(in, 0, SEEK_SET) == -1) {
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf("seek error on \"%s\": %s",
 		path, Tcl_PosixError(interp)));
-	Tcl_Close(interp, in);
+	Tcl_CloseEx(interp, in, 0);
 	return TCL_ERROR;
     }
     pos[0] = Tcl_Tell(out);
@@ -2190,7 +2188,7 @@ ZipAddFile(
     wrerr:
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		"write error on %s: %s", path, Tcl_PosixError(interp)));
-	Tcl_Close(interp, in);
+	Tcl_CloseEx(interp, in, 0);
 	return TCL_ERROR;
     }
     if ((len + pos[0]) & 3) {
@@ -2224,7 +2222,7 @@ ZipAddFile(
 			i);
 
 		Tcl_AppendObjToErrorInfo(interp, eiPtr);
-		Tcl_Close(interp, in);
+		Tcl_CloseEx(interp, in, 0);
 		return TCL_ERROR;
 	    }
 	    ret = Tcl_GetObjResult(interp);
@@ -2234,7 +2232,7 @@ ZipAddFile(
 			i);
 
 		Tcl_AppendObjToErrorInfo(interp, eiPtr);
-		Tcl_Close(interp, in);
+		Tcl_CloseEx(interp, in, 0);
 		return TCL_ERROR;
 	    }
 	    ch = (int) (r * 256);
@@ -2253,7 +2251,7 @@ ZipAddFile(
 	if (len != 12) {
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		    "write error on %s: %s", path, Tcl_PosixError(interp)));
-	    Tcl_Close(interp, in);
+	    Tcl_CloseEx(interp, in, 0);
 	    return TCL_ERROR;
 	}
 	memcpy(keys0, keys, sizeof(keys0));
@@ -2271,7 +2269,7 @@ ZipAddFile(
 	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		"compression init error on \"%s\"", path));
 	Tcl_SetErrorCode(interp, "TCL", "ZIPFS", "DEFLATE_INIT", NULL);
-	Tcl_Close(interp, in);
+	Tcl_CloseEx(interp, in, 0);
 	return TCL_ERROR;
     }
     do {
@@ -2280,7 +2278,7 @@ ZipAddFile(
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		    "read error on %s: %s", path, Tcl_PosixError(interp)));
 	    deflateEnd(&stream);
-	    Tcl_Close(interp, in);
+	    Tcl_CloseEx(interp, in, 0);
 	    return TCL_ERROR;
 	}
 	stream.avail_in = len;
@@ -2295,7 +2293,7 @@ ZipAddFile(
 			"deflate error on %s", path));
 		Tcl_SetErrorCode(interp, "TCL", "ZIPFS", "DEFLATE", NULL);
 		deflateEnd(&stream);
-		Tcl_Close(interp, in);
+		Tcl_CloseEx(interp, in, 0);
 		return TCL_ERROR;
 	    }
 	    olen = sizeof(obuf) - stream.avail_out;
@@ -2311,7 +2309,7 @@ ZipAddFile(
 		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 			"write error: %s", Tcl_PosixError(interp)));
 		deflateEnd(&stream);
-		Tcl_Close(interp, in);
+		Tcl_CloseEx(interp, in, 0);
 		return TCL_ERROR;
 	    }
 	    nbytecompr += olen;
@@ -2329,7 +2327,7 @@ ZipAddFile(
 	}
 	if (Tcl_Seek(out, pos[2], SEEK_SET) != pos[2]) {
 	seekErr:
-	    Tcl_Close(interp, in);
+	    Tcl_CloseEx(interp, in, 0);
 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 		    "seek error: %s", Tcl_PosixError(interp)));
 	    return TCL_ERROR;
@@ -2341,7 +2339,7 @@ ZipAddFile(
 		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 			"read error on \"%s\": %s",
 			path, Tcl_PosixError(interp)));
-		Tcl_Close(interp, in);
+		Tcl_CloseEx(interp, in, 0);
 		return TCL_ERROR;
 	    } else if (len == 0) {
 		break;
@@ -2357,7 +2355,7 @@ ZipAddFile(
 	    if (Tcl_Write(out, buf, len) != len) {
 		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 			"write error: %s", Tcl_PosixError(interp)));
-		Tcl_Close(interp, in);
+		Tcl_CloseEx(interp, in, 0);
 		return TCL_ERROR;
 	    }
 	    nbytecompr += len;
@@ -2367,7 +2365,7 @@ ZipAddFile(
 	pos[1] = Tcl_Tell(out);
 	Tcl_TruncateChannel(out, pos[1]);
     }
-    Tcl_Close(interp, in);
+    Tcl_CloseEx(interp, in, 0);
 
     hPtr = Tcl_CreateHashEntry(fileHash, zpath, &isNew);
     if (!isNew) {
@@ -2585,7 +2583,7 @@ ZipFSMkZipOrImgObjCmd(
 		Tcl_DecrRefCount(list);
 		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 			"write error: %s", Tcl_PosixError(interp)));
-		Tcl_Close(interp, out);
+		Tcl_CloseEx(interp, out, 0);
 		if (zf == &zf0) {
 		    ZipFSCloseArchive(interp, zf);
 		} else {
@@ -2618,7 +2616,7 @@ ZipFSMkZipOrImgObjCmd(
 	    if (!in) {
 		memset(passBuf, 0, sizeof(passBuf));
 		Tcl_DecrRefCount(list);
-		Tcl_Close(interp, out);
+		Tcl_CloseEx(interp, out, 0);
 		return TCL_ERROR;
 	    }
 	    i = Tcl_Seek(in, 0, SEEK_END);
@@ -2628,8 +2626,8 @@ ZipFSMkZipOrImgObjCmd(
 		Tcl_DecrRefCount(list);
 		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 			"%s: %s", errMsg, Tcl_PosixError(interp)));
-		Tcl_Close(interp, out);
-		Tcl_Close(interp, in);
+		Tcl_CloseEx(interp, out, 0);
+		Tcl_CloseEx(interp, in, 0);
 		return TCL_ERROR;
 	    }
 	    Tcl_Seek(in, 0, SEEK_SET);
@@ -2651,7 +2649,7 @@ ZipFSMkZipOrImgObjCmd(
 		    goto cperr;
 		}
 	    }
-	    Tcl_Close(interp, in);
+	    Tcl_CloseEx(interp, in, 0);
 	}
 	len = strlen(passBuf);
 	if (len > 0) {
@@ -2660,7 +2658,7 @@ ZipFSMkZipOrImgObjCmd(
 		Tcl_DecrRefCount(list);
 		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
 			"write error: %s", Tcl_PosixError(interp)));
-		Tcl_Close(interp, out);
+		Tcl_CloseEx(interp, out, 0);
 		return TCL_ERROR;
 	    }
 	}
@@ -2776,9 +2774,9 @@ ZipFSMkZipOrImgObjCmd(
 
   done:
     if (ret == TCL_OK) {
-	ret = Tcl_Close(interp, out);
+	ret = Tcl_CloseEx(interp, out, 0);
     } else {
-	Tcl_Close(interp, out);
+	Tcl_CloseEx(interp, out, 0);
     }
     Tcl_DecrRefCount(list);
     for (hPtr = Tcl_FirstHashEntry(&fileHash, &search); hPtr;
@@ -3332,11 +3330,16 @@ ZipFSTclLibraryObjCmd(
 static int
 ZipChannelClose(
     void *instanceData,
-    Tcl_Interp *dummy)		/* Current interpreter. */
+    Tcl_Interp *dummy,		/* Current interpreter. */
+    int flags)
 {
     ZipChannel *info = (ZipChannel *)instanceData;
     (void)dummy;
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
     if (info->iscompr && info->ubuf) {
 	Tcl_Free(info->ubuf);
 	info->ubuf = NULL;
@@ -3562,16 +3565,6 @@ ZipChannelWideSeek(
     info->numRead = (size_t) offset;
     return info->numRead;
 }
-
-static int
-ZipChannelSeek(
-    void *instanceData,
-    long offset,
-    int mode,
-    int *errloc)
-{
-    return ZipChannelWideSeek(instanceData, offset, mode, errloc);
-}
 
 /*
  *-------------------------------------------------------------------------
diff --git a/generic/tclZlib.c b/generic/tclZlib.c
index d520739..4a91e26 100644
--- a/generic/tclZlib.c
+++ b/generic/tclZlib.c
@@ -160,7 +160,7 @@ typedef struct {
 
 static Tcl_CmdDeleteProc	ZlibStreamCmdDelete;
 static Tcl_DriverBlockModeProc	ZlibTransformBlockMode;
-static Tcl_DriverCloseProc	ZlibTransformClose;
+static Tcl_DriverClose2Proc	ZlibTransformClose;
 static Tcl_DriverGetHandleProc	ZlibTransformGetHandle;
 static Tcl_DriverGetOptionProc	ZlibTransformGetOption;
 static Tcl_DriverHandlerProc	ZlibTransformEventHandler;
@@ -205,7 +205,7 @@ static void		ZlibTransformTimerRun(void *clientData);
 static const Tcl_ChannelType zlibChannelType = {
     "zlib",
     TCL_CHANNEL_VERSION_5,
-    ZlibTransformClose,
+    NULL,
     ZlibTransformInput,
     ZlibTransformOutput,
     NULL,			/* seekProc */
@@ -213,7 +213,7 @@ static const Tcl_ChannelType zlibChannelType = {
     ZlibTransformGetOption,
     ZlibTransformWatch,
     ZlibTransformGetHandle,
-    NULL,			/* close2Proc */
+	ZlibTransformClose,			/* close2Proc */
     ZlibTransformBlockMode,
     NULL,			/* flushProc */
     ZlibTransformEventHandler,
@@ -2905,12 +2905,17 @@ ZlibStreamHeaderCmd(
 static int
 ZlibTransformClose(
     void *instanceData,
-    Tcl_Interp *interp)
+    Tcl_Interp *interp,
+	int flags)
 {
     ZlibChannelData *cd = (ZlibChannelData *)instanceData;
     int e, result = TCL_OK;
     size_t written;
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
     /*
      * Delete the support timer.
      */
diff --git a/unix/tclUnixChan.c b/unix/tclUnixChan.c
index 2314ba3..7478627 100644
--- a/unix/tclUnixChan.c
+++ b/unix/tclUnixChan.c
@@ -121,15 +121,13 @@ typedef struct {
 
 static int		FileBlockModeProc(void *instanceData, int mode);
 static int		FileCloseProc(void *instanceData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static int		FileGetHandleProc(void *instanceData,
 			    int direction, void **handlePtr);
 static int		FileInputProc(void *instanceData, char *buf,
 			    int toRead, int *errorCode);
 static int		FileOutputProc(void *instanceData,
 			    const char *buf, int toWrite, int *errorCode);
-static int		FileSeekProc(void *instanceData, long offset,
-			    int mode, int *errorCode);
 static int		FileTruncateProc(void *instanceData,
 			    Tcl_WideInt length);
 static Tcl_WideInt	FileWideSeekProc(void *instanceData,
@@ -137,7 +135,7 @@ static Tcl_WideInt	FileWideSeekProc(void *instanceData,
 static void		FileWatchProc(void *instanceData, int mask);
 #ifdef SUPPORTS_TTY
 static int		TtyCloseProc(void *instanceData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static void		TtyGetAttributes(int fd, TtyAttrs *ttyPtr);
 static int		TtyGetOptionProc(void *instanceData,
 			    Tcl_Interp *interp, const char *optionName,
@@ -161,15 +159,15 @@ static int		TtySetOptionProc(void *instanceData,
 static const Tcl_ChannelType fileChannelType = {
     "file",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    FileCloseProc,		/* Close proc. */
+    NULL,		/* Close proc. */
     FileInputProc,		/* Input proc. */
     FileOutputProc,		/* Output proc. */
-    FileSeekProc,		/* Seek proc. */
+	NULL,
     NULL,			/* Set option proc. */
     NULL,			/* Get option proc. */
     FileWatchProc,		/* Initialize notifier. */
     FileGetHandleProc,		/* Get OS handles out of channel. */
-    NULL,			/* close2proc. */
+    FileCloseProc,		/* close2proc. */
     FileBlockModeProc,		/* Set blocking or non-blocking mode.*/
     NULL,			/* flush proc. */
     NULL,			/* handler proc. */
@@ -187,7 +185,7 @@ static const Tcl_ChannelType fileChannelType = {
 static const Tcl_ChannelType ttyChannelType = {
     "tty",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    TtyCloseProc,		/* Close proc. */
+    NULL,		/* Close proc. */
     FileInputProc,		/* Input proc. */
     FileOutputProc,		/* Output proc. */
     NULL,			/* Seek proc. */
@@ -195,7 +193,7 @@ static const Tcl_ChannelType ttyChannelType = {
     TtyGetOptionProc,		/* Get option proc. */
     FileWatchProc,		/* Initialize notifier. */
     FileGetHandleProc,		/* Get OS handles out of channel. */
-    NULL,			/* close2proc. */
+    TtyCloseProc,			/* close2proc. */
     FileBlockModeProc,		/* Set blocking or non-blocking mode.*/
     NULL,			/* flush proc. */
     NULL,			/* handler proc. */
@@ -353,12 +351,17 @@ FileOutputProc(
 static int
 FileCloseProc(
     void *instanceData,	/* File state. */
-    Tcl_Interp *dummy)		/* For error reporting - unused. */
+    Tcl_Interp *dummy,		/* For error reporting - unused. */
+    int flags)
 {
     FileState *fsPtr = (FileState *)instanceData;
     int errorCode = 0;
     (void)dummy;
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
     Tcl_DeleteFileHandler(fsPtr->fd);
 
     /*
@@ -379,10 +382,14 @@ FileCloseProc(
 static int
 TtyCloseProc(
     void *instanceData,
-    Tcl_Interp *interp)
+    Tcl_Interp *interp,
+	int flags)
 {
     TtyState *ttyPtr = (TtyState*)instanceData;
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
     /*
      * If we've been asked by the user to drain or flush, do so now.
      */
@@ -411,73 +418,13 @@ TtyCloseProc(
      * Delegate to close for files.
      */
 
-    return FileCloseProc(instanceData, interp);
+    return FileCloseProc(instanceData, interp, flags);
 }
 #endif /* SUPPORTS_TTY */
 
 /*
  *----------------------------------------------------------------------
  *
- * FileSeekProc --
- *
- *	This function is called by the generic IO level to move the access
- *	point in a file based channel.
- *
- * Results:
- *	-1 if failed, the new position if successful. An output argument
- *	contains the POSIX error code if an error occurred, or zero.
- *
- * Side effects:
- *	Moves the location at which the channel will be accessed in future
- *	operations.
- *
- *----------------------------------------------------------------------
- */
-
-static int
-FileSeekProc(
-    void *instanceData,	/* File state. */
-    long offset,		/* Offset to seek to. */
-    int mode,			/* Relative to where should we seek? Can be
-				 * one of SEEK_START, SEEK_SET or SEEK_END. */
-    int *errorCodePtr)		/* To store error code. */
-{
-    FileState *fsPtr = (FileState *)instanceData;
-    Tcl_WideInt oldLoc, newLoc;
-
-    /*
-     * Save our current place in case we need to roll-back the seek.
-     */
-
-    oldLoc = TclOSseek(fsPtr->fd, (Tcl_SeekOffset) 0, SEEK_CUR);
-    if (oldLoc == -1) {
-	/*
-	 * Bad things are happening. Error out...
-	 */
-
-	*errorCodePtr = errno;
-	return -1;
-    }
-
-    newLoc = TclOSseek(fsPtr->fd, (Tcl_SeekOffset) offset, mode);
-
-    /*
-     * Check for expressability in our return type, and roll-back otherwise.
-     */
-
-    if (newLoc > INT_MAX) {
-	*errorCodePtr = EOVERFLOW;
-	TclOSseek(fsPtr->fd, (Tcl_SeekOffset) oldLoc, SEEK_SET);
-	return -1;
-    } else {
-	*errorCodePtr = (newLoc == -1) ? errno : 0;
-    }
-    return (int) newLoc;
-}
-
-/*
- *----------------------------------------------------------------------
- *
  * FileWideSeekProc --
  *
  *	This function is called by the generic IO level to move the access
@@ -1738,7 +1685,7 @@ TclpOpenFileChannel(
 
 	if (Tcl_SetChannelOption(interp, fsPtr->fileState.channel,
 		"-translation", translation) != TCL_OK) {
-	    Tcl_Close(NULL, fsPtr->fileState.channel);
+	    Tcl_CloseEx(NULL, fsPtr->fileState.channel, 0);
 	    return NULL;
 	}
     }
diff --git a/unix/tclUnixPipe.c b/unix/tclUnixPipe.c
index 55fd03d..a0445a2 100644
--- a/unix/tclUnixPipe.c
+++ b/unix/tclUnixPipe.c
@@ -69,7 +69,7 @@ static int		SetupStdFile(TclFile file, int type);
 static const Tcl_ChannelType pipeChannelType = {
     "pipe",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    TCL_CLOSE2PROC,		/* Close proc. */
+    NULL,		/* Close proc. */
     PipeInputProc,		/* Input proc. */
     PipeOutputProc,		/* Output proc. */
     NULL,			/* Seek proc. */
diff --git a/unix/tclUnixSock.c b/unix/tclUnixSock.c
index 0fa4edf..f72a888 100644
--- a/unix/tclUnixSock.c
+++ b/unix/tclUnixSock.c
@@ -157,7 +157,7 @@ static void		WrapNotify(void *clientData, int mask);
 static const Tcl_ChannelType tcpChannelType = {
     "tcp",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    TcpCloseProc,		/* Close proc. */
+    NULL,		/* Close proc. */
     TcpInputProc,		/* Input proc. */
     TcpOutputProc,		/* Output proc. */
     NULL,			/* Seek proc. */
@@ -1419,7 +1419,7 @@ Tcl_OpenTcpClient(
             statePtr, TCL_READABLE | TCL_WRITABLE);
     if (Tcl_SetChannelOption(interp, statePtr->channel, "-translation",
 	    "auto crlf") == TCL_ERROR) {
-	Tcl_Close(NULL, statePtr->channel);
+	Tcl_CloseEx(NULL, statePtr->channel, 0);
 	return NULL;
     }
     return statePtr->channel;
@@ -1486,7 +1486,7 @@ TclpMakeTcpClientChannelMode(
 	    statePtr, mode);
     if (Tcl_SetChannelOption(NULL, statePtr->channel, "-translation",
 	    "auto crlf") == TCL_ERROR) {
-	Tcl_Close(NULL, statePtr->channel);
+	Tcl_CloseEx(NULL, statePtr->channel, 0);
 	return NULL;
     }
     return statePtr->channel;
diff --git a/win/tclWinChan.c b/win/tclWinChan.c
index 23a3545..aa002f3 100644
--- a/win/tclWinChan.c
+++ b/win/tclWinChan.c
@@ -76,7 +76,7 @@ static int		FileBlockProc(ClientData instanceData, int mode);
 static void		FileChannelExitHandler(ClientData clientData);
 static void		FileCheckProc(ClientData clientData, int flags);
 static int		FileCloseProc(ClientData instanceData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static int		FileEventProc(Tcl_Event *evPtr, int flags);
 static int		FileGetHandleProc(ClientData instanceData,
 			    int direction, ClientData *handlePtr);
@@ -85,8 +85,6 @@ static int		FileInputProc(ClientData instanceData, char *buf,
 			    int toRead, int *errorCode);
 static int		FileOutputProc(ClientData instanceData,
 			    const char *buf, int toWrite, int *errorCode);
-static int		FileSeekProc(ClientData instanceData, long offset,
-			    int mode, int *errorCode);
 static Tcl_WideInt	FileWideSeekProc(ClientData instanceData,
 			    Tcl_WideInt offset, int mode, int *errorCode);
 static void		FileSetupProc(ClientData clientData, int flags);
@@ -105,15 +103,15 @@ static int		NativeIsComPort(const WCHAR *nativeName);
 static const Tcl_ChannelType fileChannelType = {
     "file",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    FileCloseProc,		/* Close proc. */
+    NULL,		/* Close proc. */
     FileInputProc,		/* Input proc. */
     FileOutputProc,		/* Output proc. */
-    FileSeekProc,		/* Seek proc. */
+	NULL,
     NULL,			/* Set option proc. */
     NULL,			/* Get option proc. */
     FileWatchProc,		/* Set up the notifier to watch the channel. */
     FileGetHandleProc,		/* Get an OS handle from channel. */
-    NULL,			/* close2proc. */
+    FileCloseProc,		/* close2proc. */
     FileBlockProc,		/* Set blocking or non-blocking mode.*/
     NULL,			/* flush proc. */
     NULL,			/* handler proc. */
@@ -390,7 +388,8 @@ FileBlockProc(
 static int
 FileCloseProc(
     ClientData instanceData,	/* Pointer to FileInfo structure. */
-    Tcl_Interp *dummy)		/* Not used. */
+    Tcl_Interp *dummy,		/* Not used. */
+    int flags)
 {
     FileInfo *fileInfoPtr = (FileInfo *)instanceData;
     FileInfo *infoPtr;
@@ -398,6 +397,10 @@ FileCloseProc(
     int errorCode = 0;
     (void)dummy;
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
     /*
      * Remove the file from the watch list.
      */
@@ -446,84 +449,6 @@ FileCloseProc(
 /*
  *----------------------------------------------------------------------
  *
- * FileSeekProc --
- *
- *	Seeks on a file-based channel. Returns the new position.
- *
- * Results:
- *	-1 if failed, the new position if successful. If failed, it also sets
- *	*errorCodePtr to the error code.
- *
- * Side effects:
- *	Moves the location at which the channel will be accessed in future
- *	operations.
- *
- *----------------------------------------------------------------------
- */
-
-static int
-FileSeekProc(
-    ClientData instanceData,	/* File state. */
-    long offset,		/* Offset to seek to. */
-    int mode,			/* Relative to where should we seek? */
-    int *errorCodePtr)		/* To store error code. */
-{
-    FileInfo *infoPtr = (FileInfo *)instanceData;
-    LONG newPos, newPosHigh, oldPos, oldPosHigh;
-    DWORD moveMethod;
-
-    *errorCodePtr = 0;
-    if (mode == SEEK_SET) {
-	moveMethod = FILE_BEGIN;
-    } else if (mode == SEEK_CUR) {
-	moveMethod = FILE_CURRENT;
-    } else {
-	moveMethod = FILE_END;
-    }
-
-    /*
-     * Save our current place in case we need to roll-back the seek.
-     */
-
-    oldPosHigh = 0;
-    oldPos = SetFilePointer(infoPtr->handle, 0, &oldPosHigh, FILE_CURRENT);
-    if (oldPos == (LONG) INVALID_SET_FILE_POINTER) {
-	DWORD winError = GetLastError();
-
-	if (winError != NO_ERROR) {
-	    TclWinConvertError(winError);
-	    *errorCodePtr = errno;
-	    return -1;
-	}
-    }
-
-    newPosHigh = (offset < 0 ? -1 : 0);
-    newPos = SetFilePointer(infoPtr->handle, offset, &newPosHigh, moveMethod);
-    if (newPos == (LONG) INVALID_SET_FILE_POINTER) {
-	DWORD winError = GetLastError();
-
-	if (winError != NO_ERROR) {
-	    TclWinConvertError(winError);
-	    *errorCodePtr = errno;
-	    return -1;
-	}
-    }
-
-    /*
-     * Check for expressability in our return type, and roll-back otherwise.
-     */
-
-    if (newPosHigh != 0) {
-	*errorCodePtr = EOVERFLOW;
-	SetFilePointer(infoPtr->handle, oldPos, &oldPosHigh, FILE_BEGIN);
-	return -1;
-    }
-    return (int) newPos;
-}
-
-/*
- *----------------------------------------------------------------------
- *
  * FileWideSeekProc --
  *
  *	Seeks on a file-based channel. Returns the new position.
@@ -1320,7 +1245,7 @@ TclpGetDefaultStdChannel(
     if (Tcl_SetChannelOption(NULL,channel,"-translation","auto")!=TCL_OK ||
 	    Tcl_SetChannelOption(NULL,channel,"-eofchar","\032 {}")!=TCL_OK ||
 	    Tcl_SetChannelOption(NULL,channel,"-buffering",bufMode)!=TCL_OK) {
-	Tcl_Close(NULL, channel);
+	Tcl_CloseEx(NULL, channel, 0);
 	return (Tcl_Channel) NULL;
     }
     return channel;
diff --git a/win/tclWinConsole.c b/win/tclWinConsole.c
index b92be89..58082d7 100644
--- a/win/tclWinConsole.c
+++ b/win/tclWinConsole.c
@@ -142,7 +142,7 @@ static int		ConsoleBlockModeProc(ClientData instanceData,
 			    int mode);
 static void		ConsoleCheckProc(ClientData clientData, int flags);
 static int		ConsoleCloseProc(ClientData instanceData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static int		ConsoleEventProc(Tcl_Event *evPtr, int flags);
 static void		ConsoleExitHandler(ClientData clientData);
 static int		ConsoleGetHandleProc(ClientData instanceData,
@@ -180,7 +180,7 @@ static BOOL		WriteConsoleBytes(HANDLE hConsole,
 static const Tcl_ChannelType consoleChannelType = {
     "console",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    ConsoleCloseProc,		/* Close proc. */
+    NULL,		/* Close proc. */
     ConsoleInputProc,		/* Input proc. */
     ConsoleOutputProc,		/* Output proc. */
     NULL,			/* Seek proc. */
@@ -188,7 +188,7 @@ static const Tcl_ChannelType consoleChannelType = {
     ConsoleGetOptionProc,	/* Get option proc. */
     ConsoleWatchProc,		/* Set up notifier to watch the channel. */
     ConsoleGetHandleProc,	/* Get an OS handle from channel. */
-    NULL,			/* close2proc. */
+    ConsoleCloseProc,		/* close2proc. */
     ConsoleBlockModeProc,	/* Set blocking or non-blocking mode. */
     NULL,			/* Flush proc. */
     NULL,			/* Handler proc. */
@@ -537,7 +537,8 @@ ConsoleBlockModeProc(
 static int
 ConsoleCloseProc(
     ClientData instanceData,	/* Pointer to ConsoleInfo structure. */
-    Tcl_Interp *dummy)		/* For error reporting. */
+    Tcl_Interp *dummy,		/* For error reporting. */
+    int flags)
 {
     ConsoleInfo *consolePtr = (ConsoleInfo *)instanceData;
     int errorCode = 0;
@@ -545,6 +546,10 @@ ConsoleCloseProc(
     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
     (void)dummy;
 
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
     /*
      * Clean up the background thread if necessary. Note that this must be
      * done before we can close the file, since the thread may be blocking
diff --git a/win/tclWinPipe.c b/win/tclWinPipe.c
index 4d2b20a..d21425b 100644
--- a/win/tclWinPipe.c
+++ b/win/tclWinPipe.c
@@ -203,7 +203,7 @@ static void		PipeThreadActionProc(ClientData instanceData,
 static const Tcl_ChannelType pipeChannelType = {
     "pipe",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    TCL_CLOSE2PROC,		/* Close proc. */
+    NULL,		/* Close proc. */
     PipeInputProc,		/* Input proc. */
     PipeOutputProc,		/* Output proc. */
     NULL,			/* Seek proc. */
diff --git a/win/tclWinSerial.c b/win/tclWinSerial.c
index bcc7983..e529f77 100644
--- a/win/tclWinSerial.c
+++ b/win/tclWinSerial.c
@@ -168,7 +168,7 @@ static COMMTIMEOUTS no_timeout = {
 static int		SerialBlockProc(ClientData instanceData, int mode);
 static void		SerialCheckProc(ClientData clientData, int flags);
 static int		SerialCloseProc(ClientData instanceData,
-			    Tcl_Interp *interp);
+			    Tcl_Interp *interp, int flags);
 static int		SerialEventProc(Tcl_Event *evPtr, int flags);
 static void		SerialExitHandler(ClientData clientData);
 static int		SerialGetHandleProc(ClientData instanceData,
@@ -204,7 +204,7 @@ static int		SerialBlockingWrite(SerialInfo *infoPtr, LPVOID buf,
 static const Tcl_ChannelType serialChannelType = {
     "serial",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    SerialCloseProc,		/* Close proc. */
+    NULL,		/* Close proc. */
     SerialInputProc,		/* Input proc. */
     SerialOutputProc,		/* Output proc. */
     NULL,			/* Seek proc. */
@@ -212,7 +212,7 @@ static const Tcl_ChannelType serialChannelType = {
     SerialGetOptionProc,	/* Get option proc. */
     SerialWatchProc,		/* Set up notifier to watch the channel. */
     SerialGetHandleProc,	/* Get an OS handle from channel. */
-    NULL,			/* close2proc. */
+    SerialCloseProc,		/* close2proc. */
     SerialBlockProc,		/* Set blocking or non-blocking mode.*/
     NULL,			/* flush proc. */
     NULL,			/* handler proc. */
@@ -606,15 +606,19 @@ SerialBlockProc(
 static int
 SerialCloseProc(
     ClientData instanceData,    /* Pointer to SerialInfo structure. */
-    Tcl_Interp *dummy)		/* For error reporting. */
+    Tcl_Interp *dummy,		/* For error reporting. */
+    int flags)
 {
     SerialInfo *serialPtr = (SerialInfo *) instanceData;
-    int errorCode, result = 0;
+    int errorCode = 0, result = 0;
     SerialInfo *infoPtr, **nextPtrPtr;
     ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
     (void)dummy;
 
-    errorCode = 0;
+    if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) != 0) {
+	return EINVAL;
+    }
+
 
     if (serialPtr->validMask & TCL_READABLE) {
 	PurgeComm(serialPtr->handle, PURGE_RXABORT | PURGE_RXCLEAR);
diff --git a/win/tclWinSock.c b/win/tclWinSock.c
index c6d5501..a1eaa18 100644
--- a/win/tclWinSock.c
+++ b/win/tclWinSock.c
@@ -280,7 +280,7 @@ static Tcl_DriverGetHandleProc	TcpGetHandleProc;
 static const Tcl_ChannelType tcpChannelType = {
     "tcp",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    TcpCloseProc,		/* Close proc. */
+    NULL,		/* Close proc. */
     TcpInputProc,		/* Input proc. */
     TcpOutputProc,		/* Output proc. */
     NULL,			/* Seek proc. */
@@ -2108,11 +2108,11 @@ Tcl_OpenTcpClient(
 	    statePtr, (TCL_READABLE | TCL_WRITABLE));
     if (TCL_ERROR == Tcl_SetChannelOption(NULL, statePtr->channel,
 	    "-translation", "auto crlf")) {
-	Tcl_Close(NULL, statePtr->channel);
+	Tcl_CloseEx(NULL, statePtr->channel, 0);
 	return NULL;
     } else if (TCL_ERROR == Tcl_SetChannelOption(NULL, statePtr->channel,
 	    "-eofchar", "")) {
-	Tcl_Close(NULL, statePtr->channel);
+	Tcl_CloseEx(NULL, statePtr->channel, 0);
 	return NULL;
     }
     return statePtr->channel;
@@ -2360,7 +2360,7 @@ Tcl_OpenTcpServerEx(
 	SendSelectMessage(tsdPtr, SELECT, statePtr);
 	if (Tcl_SetChannelOption(interp, statePtr->channel, "-eofchar", "")
 	    == TCL_ERROR) {
-	    Tcl_Close(NULL, statePtr->channel);
+	    Tcl_CloseEx(NULL, statePtr->channel, 0);
 	    return NULL;
 	}
 	return statePtr->channel;
@@ -2433,12 +2433,12 @@ TcpAccept(
 	    newInfoPtr, (TCL_READABLE | TCL_WRITABLE));
     if (Tcl_SetChannelOption(NULL, newInfoPtr->channel, "-translation",
 	    "auto crlf") == TCL_ERROR) {
-	Tcl_Close(NULL, newInfoPtr->channel);
+	Tcl_CloseEx(NULL, newInfoPtr->channel, 0);
 	return;
     }
     if (Tcl_SetChannelOption(NULL, newInfoPtr->channel, "-eofchar", "")
 	    == TCL_ERROR) {
-	Tcl_Close(NULL, newInfoPtr->channel);
+	Tcl_CloseEx(NULL, newInfoPtr->channel, 0);
 	return;
     }