Merge commit '6b095f3c8521ca7215e6ff5dcbada52b197ef7d0' as 'tk8.6'

1 files changed, 721 insertions, 0 deletions

diff --git a/tk8.6/generic/tkClipboard.c b/tk8.6/generic/tkClipboard.c
new file mode 100644
index 0000000..b902625
--- /dev/null
+++ b/tk8.6/generic/tkClipboard.c
@@ -0,0 +1,721 @@
+/*
+ * tkClipboard.c --
+ *
+ * 	This file manages the clipboard for the Tk toolkit, maintaining a
+ * 	collection of data buffers that will be supplied on demand to
+ * 	requesting applications.
+ *
+ * Copyright (c) 1994 The Regents of the University of California.
+ * Copyright (c) 1994-1997 Sun Microsystems, Inc.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+#include "tkInt.h"
+#include "tkSelect.h"
+
+/*
+ * Prototypes for functions used only in this file:
+ */
+
+static int		ClipboardAppHandler(ClientData clientData,
+			    int offset, char *buffer, int maxBytes);
+static int		ClipboardHandler(ClientData clientData,
+			    int offset, char *buffer, int maxBytes);
+static int		ClipboardWindowHandler(ClientData clientData,
+			    int offset, char *buffer, int maxBytes);
+static void		ClipboardLostSel(ClientData clientData);
+static int		ClipboardGetProc(ClientData clientData,
+			    Tcl_Interp *interp, const char *portion);
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClipboardHandler --
+ *
+ *	This function acts as selection handler for the clipboard manager. It
+ *	extracts the required chunk of data from the buffer chain for a given
+ *	selection target.
+ *
+ * Results:
+ *	The return value is a count of the number of bytes actually stored at
+ *	buffer.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+ClipboardHandler(
+    ClientData clientData,	/* Information about data to fetch. */
+    int offset,			/* Return selection bytes starting at this
+				 * offset. */
+    char *buffer,		/* Place to store converted selection. */
+    int maxBytes)		/* Maximum # of bytes to store at buffer. */
+{
+    TkClipboardTarget *targetPtr = clientData;
+    TkClipboardBuffer *cbPtr;
+    char *srcPtr, *destPtr;
+    size_t count = 0;
+    int scanned = 0;
+    size_t length, freeCount;
+
+    /*
+     * Skip to buffer containing offset byte
+     */
+
+    for (cbPtr = targetPtr->firstBufferPtr; ; cbPtr = cbPtr->nextPtr) {
+	if (cbPtr == NULL) {
+	    return 0;
+	}
+	if (scanned + cbPtr->length > offset) {
+	    break;
+	}
+	scanned += cbPtr->length;
+    }
+
+    /*
+     * Copy up to maxBytes or end of list, switching buffers as needed.
+     */
+
+    freeCount = maxBytes;
+    srcPtr = cbPtr->buffer + (offset - scanned);
+    destPtr = buffer;
+    length = cbPtr->length - (offset - scanned);
+    while (1) {
+	if (length > freeCount) {
+	    strncpy(destPtr, srcPtr, freeCount);
+	    return maxBytes;
+	} else {
+	    strncpy(destPtr, srcPtr, length);
+	    destPtr += length;
+	    count += length;
+	    freeCount -= length;
+	}
+	cbPtr = cbPtr->nextPtr;
+	if (cbPtr == NULL) {
+	    break;
+	}
+	srcPtr = cbPtr->buffer;
+	length = cbPtr->length;
+    }
+    return (int)count;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClipboardAppHandler --
+ *
+ *	This function acts as selection handler for retrievals of type
+ *	TK_APPLICATION. It returns the name of the application that owns the
+ *	clipboard. Note: we can't use the default Tk selection handler for
+ *	this selection type, because the clipboard window isn't a "real"
+ *	window and doesn't have the necessary information.
+ *
+ * Results:
+ *	The return value is a count of the number of bytes actually stored at
+ *	buffer.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+ClipboardAppHandler(
+    ClientData clientData,	/* Pointer to TkDisplay structure. */
+    int offset,			/* Return selection bytes starting at this
+				 * offset. */
+    char *buffer,		/* Place to store converted selection. */
+    int maxBytes)		/* Maximum # of bytes to store at buffer. */
+{
+    TkDisplay *dispPtr = clientData;
+    size_t length;
+    const char *p;
+
+    p = dispPtr->clipboardAppPtr->winPtr->nameUid;
+    length = strlen(p);
+    length -= offset;
+    if (length <= 0) {
+	return 0;
+    }
+    if (length > (size_t) maxBytes) {
+	length = maxBytes;
+    }
+    strncpy(buffer, p, length);
+    return (int)length;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClipboardWindowHandler --
+ *
+ *	This function acts as selection handler for retrievals of type
+ *	TK_WINDOW. Since the clipboard doesn't correspond to any particular
+ *	window, we just return ".". We can't use Tk's default handler for this
+ *	selection type, because the clipboard window isn't a valid window.
+ *
+ * Results:
+ *	The return value is 1, the number of non-null bytes stored at buffer.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+ClipboardWindowHandler(
+    ClientData clientData,	/* Not used. */
+    int offset,			/* Return selection bytes starting at this
+				 * offset. */
+    char *buffer,		/* Place to store converted selection. */
+    int maxBytes)		/* Maximum # of bytes to store at buffer. */
+{
+    buffer[0] = '.';
+    buffer[1] = 0;
+    return 1;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClipboardLostSel --
+ *
+ *	This function is invoked whenever clipboard ownership is claimed by
+ *	another window. It just sets a flag so that we know the clipboard was
+ *	taken away.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The clipboard is marked as inactive.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+ClipboardLostSel(
+    ClientData clientData)	/* Pointer to TkDisplay structure. */
+{
+    TkDisplay *dispPtr = clientData;
+
+    dispPtr->clipboardActive = 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tk_ClipboardClear --
+ *
+ *	Take control of the clipboard and clear out the previous contents.
+ *	This function must be invoked before any calls to Tk_ClipboardAppend.
+ *
+ * Results:
+ *	A standard Tcl result. If an error occurs, an error message is left in
+ *	the interp's result.
+ *
+ * Side effects:
+ *	From now on, requests for the CLIPBOARD selection will be directed to
+ *	the clipboard manager routines associated with clipWindow for the
+ *	display of tkwin. In order to guarantee atomicity, no event handling
+ *	should occur between Tk_ClipboardClear and the following
+ *	Tk_ClipboardAppend calls. This function may cause a user-defined
+ *	LostSel command to be invoked when the CLIPBOARD is claimed, so any
+ *	calling function should be reentrant at the point Tk_ClipboardClear is
+ *	invoked.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tk_ClipboardClear(
+    Tcl_Interp *interp,		/* Interpreter to use for error reporting. */
+    Tk_Window tkwin)		/* Window in application that is clearing
+				 * clipboard; identifies application and
+				 * display. */
+{
+    TkWindow *winPtr = (TkWindow *) tkwin;
+    TkDisplay *dispPtr = winPtr->dispPtr;
+    TkClipboardTarget *targetPtr, *nextTargetPtr;
+    TkClipboardBuffer *cbPtr, *nextCbPtr;
+
+    if (dispPtr->clipWindow == NULL) {
+	int result;
+
+	result = TkClipInit(interp, dispPtr);
+	if (result != TCL_OK) {
+	    return result;
+	}
+    }
+
+    /*
+     * Discard any existing clipboard data and delete the selection handler(s)
+     * associated with that data.
+     */
+
+    for (targetPtr = dispPtr->clipTargetPtr; targetPtr != NULL;
+	    targetPtr = nextTargetPtr) {
+	for (cbPtr = targetPtr->firstBufferPtr; cbPtr != NULL;
+		cbPtr = nextCbPtr) {
+	    ckfree(cbPtr->buffer);
+	    nextCbPtr = cbPtr->nextPtr;
+	    ckfree(cbPtr);
+	}
+	nextTargetPtr = targetPtr->nextPtr;
+	Tk_DeleteSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom,
+		targetPtr->type);
+	ckfree(targetPtr);
+    }
+    dispPtr->clipTargetPtr = NULL;
+
+    /*
+     * Reclaim the clipboard selection if we lost it.
+     */
+
+    if (!dispPtr->clipboardActive) {
+	Tk_OwnSelection(dispPtr->clipWindow, dispPtr->clipboardAtom,
+		ClipboardLostSel, dispPtr);
+	dispPtr->clipboardActive = 1;
+    }
+    dispPtr->clipboardAppPtr = winPtr->mainPtr;
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tk_ClipboardAppend --
+ *
+ *	Append a buffer of data to the clipboard. The first buffer of a given
+ *	type determines the format for that type. Any successive appends to
+ *	that type must have the same format or an error will be returned.
+ *	Tk_ClipboardClear must be called before a sequence of
+ *	Tk_ClipboardAppend calls can be issued. In order to guarantee
+ *	atomicity, no event handling should occur between Tk_ClipboardClear
+ *	and the following Tk_ClipboardAppend calls.
+ *
+ * Results:
+ *	A standard Tcl result. If an error is returned, an error message is
+ *	left in the interp's result.
+ *
+ * Side effects:
+ *	The specified buffer will be copied onto the end of the clipboard.
+ *	The clipboard maintains a list of buffers which will be used to supply
+ *	the data for a selection get request. The first time a given type is
+ *	appended, Tk_ClipboardAppend will register a selection handler of the
+ *	appropriate type.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tk_ClipboardAppend(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tk_Window tkwin,		/* Window that selects a display. */
+    Atom type,			/* The desired conversion type for this
+				 * clipboard item, e.g. STRING or LENGTH. */
+    Atom format,		/* Format in which the selection information
+				 * should be returned to the requestor. */
+    const char *buffer)		/* NULL terminated string containing the data
+				 * to be added to the clipboard. */
+{
+    TkWindow *winPtr = (TkWindow *) tkwin;
+    TkDisplay *dispPtr = winPtr->dispPtr;
+    TkClipboardTarget *targetPtr;
+    TkClipboardBuffer *cbPtr;
+
+    /*
+     * If this application doesn't already own the clipboard, clear the
+     * clipboard. If we don't own the clipboard selection, claim it.
+     */
+
+    if (dispPtr->clipboardAppPtr != winPtr->mainPtr) {
+	Tk_ClipboardClear(interp, tkwin);
+    } else if (!dispPtr->clipboardActive) {
+	Tk_OwnSelection(dispPtr->clipWindow, dispPtr->clipboardAtom,
+		ClipboardLostSel, dispPtr);
+	dispPtr->clipboardActive = 1;
+    }
+
+    /*
+     * Check to see if the specified target is already present on the
+     * clipboard. If it isn't, we need to create a new target; otherwise, we
+     * just append the new buffer to the clipboard list.
+     */
+
+    for (targetPtr = dispPtr->clipTargetPtr; targetPtr != NULL;
+	    targetPtr = targetPtr->nextPtr) {
+	if (targetPtr->type == type) {
+	    break;
+	}
+    }
+    if (targetPtr == NULL) {
+	targetPtr = ckalloc(sizeof(TkClipboardTarget));
+	targetPtr->type = type;
+	targetPtr->format = format;
+	targetPtr->firstBufferPtr = targetPtr->lastBufferPtr = NULL;
+	targetPtr->nextPtr = dispPtr->clipTargetPtr;
+	dispPtr->clipTargetPtr = targetPtr;
+	Tk_CreateSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom,
+		type, ClipboardHandler, targetPtr, format);
+    } else if (targetPtr->format != format) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"format \"%s\" does not match current format \"%s\" for %s",
+		Tk_GetAtomName(tkwin, format),
+		Tk_GetAtomName(tkwin, targetPtr->format),
+		Tk_GetAtomName(tkwin, type)));
+	Tcl_SetErrorCode(interp, "TK", "CLIPBOARD", "FORMAT_MISMATCH", NULL);
+	return TCL_ERROR;
+    }
+
+    /*
+     * Append a new buffer to the buffer chain.
+     */
+
+    cbPtr = ckalloc(sizeof(TkClipboardBuffer));
+    cbPtr->nextPtr = NULL;
+    if (targetPtr->lastBufferPtr != NULL) {
+	targetPtr->lastBufferPtr->nextPtr = cbPtr;
+    } else {
+	targetPtr->firstBufferPtr = cbPtr;
+    }
+    targetPtr->lastBufferPtr = cbPtr;
+
+    cbPtr->length = strlen(buffer);
+    cbPtr->buffer = ckalloc(cbPtr->length + 1);
+    strcpy(cbPtr->buffer, buffer);
+
+    TkSelUpdateClipboard((TkWindow *) dispPtr->clipWindow, targetPtr);
+
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tk_ClipboardObjCmd --
+ *
+ *	This function is invoked to process the "clipboard" Tcl command. See
+ *	the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tk_ClipboardObjCmd(
+    ClientData clientData,	/* Main window associated with interpreter. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument strings. */
+{
+    Tk_Window tkwin = (Tk_Window) clientData;
+    const char *path = NULL;
+    Atom selection;
+    static const char *const optionStrings[] = { "append", "clear", "get", NULL };
+    enum options { CLIPBOARD_APPEND, CLIPBOARD_CLEAR, CLIPBOARD_GET };
+    int index, i;
+
+    if (objc < 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "option ?arg ...?");
+	return TCL_ERROR;
+    }
+
+    if (Tcl_GetIndexFromObj(interp, objv[1], optionStrings, "option", 0,
+	    &index) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    switch ((enum options) index) {
+    case CLIPBOARD_APPEND: {
+	Atom target, format;
+	const char *targetName = NULL;
+	const char *formatName = NULL;
+	const char *string;
+	static const char *const appendOptionStrings[] = {
+	    "-displayof", "-format", "-type", NULL
+	};
+	enum appendOptions { APPEND_DISPLAYOF, APPEND_FORMAT, APPEND_TYPE };
+	int subIndex, length;
+
+	for (i = 2; i < objc - 1; i++) {
+	    string = Tcl_GetStringFromObj(objv[i], &length);
+	    if (string[0] != '-') {
+		break;
+	    }
+
+	    /*
+	     * If the argument is "--", it signifies the end of arguments.
+	     */
+	    if (string[1] == '-' && length == 2) {
+		i++;
+		break;
+	    }
+	    if (Tcl_GetIndexFromObj(interp, objv[i], appendOptionStrings,
+		    "option", 0, &subIndex) != TCL_OK) {
+		return TCL_ERROR;
+	    }
+
+	    /*
+	     * Increment i so that it points to the value for the flag instead
+	     * of the flag itself.
+	     */
+
+	    i++;
+	    if (i >= objc) {
+		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+			"value for \"%s\" missing", string));
+		Tcl_SetErrorCode(interp, "TK", "CLIPBOARD", "VALUE", NULL);
+		return TCL_ERROR;
+	    }
+	    switch ((enum appendOptions) subIndex) {
+	    case APPEND_DISPLAYOF:
+		path = Tcl_GetString(objv[i]);
+		break;
+	    case APPEND_FORMAT:
+		formatName = Tcl_GetString(objv[i]);
+		break;
+	    case APPEND_TYPE:
+		targetName = Tcl_GetString(objv[i]);
+		break;
+	    }
+	}
+	if (objc - i != 1) {
+	    Tcl_WrongNumArgs(interp, 2, objv, "?-option value ...? data");
+	    return TCL_ERROR;
+	}
+	if (path != NULL) {
+	    tkwin = Tk_NameToWindow(interp, path, tkwin);
+	}
+	if (tkwin == NULL) {
+	    return TCL_ERROR;
+	}
+	if (targetName != NULL) {
+	    target = Tk_InternAtom(tkwin, targetName);
+	} else {
+	    target = XA_STRING;
+	}
+	if (formatName != NULL) {
+	    format = Tk_InternAtom(tkwin, formatName);
+	} else {
+	    format = XA_STRING;
+	}
+	return Tk_ClipboardAppend(interp, tkwin, target, format,
+		Tcl_GetString(objv[i]));
+    }
+    case CLIPBOARD_CLEAR: {
+	static const char *const clearOptionStrings[] = { "-displayof", NULL };
+	enum clearOptions { CLEAR_DISPLAYOF };
+	int subIndex;
+
+	if (objc != 2 && objc != 4) {
+	    Tcl_WrongNumArgs(interp, 2, objv, "?-displayof window?");
+	    return TCL_ERROR;
+	}
+
+	if (objc == 4) {
+	    if (Tcl_GetIndexFromObj(interp, objv[2], clearOptionStrings,
+		    "option", 0, &subIndex) != TCL_OK) {
+		return TCL_ERROR;
+	    }
+	    if ((enum clearOptions) subIndex == CLEAR_DISPLAYOF) {
+		path = Tcl_GetString(objv[3]);
+	    }
+	}
+	if (path != NULL) {
+	    tkwin = Tk_NameToWindow(interp, path, tkwin);
+	}
+	if (tkwin == NULL) {
+	    return TCL_ERROR;
+	}
+	return Tk_ClipboardClear(interp, tkwin);
+    }
+    case CLIPBOARD_GET: {
+	Atom target;
+	const char *targetName = NULL;
+	Tcl_DString selBytes;
+	int result;
+	const char *string;
+	static const char *const getOptionStrings[] = {
+	    "-displayof", "-type", NULL
+	};
+	enum getOptions { APPEND_DISPLAYOF, APPEND_TYPE };
+	int subIndex;
+
+	for (i = 2; i < objc; i++) {
+	    string = Tcl_GetString(objv[i]);
+	    if (string[0] != '-') {
+		break;
+	    }
+	    if (Tcl_GetIndexFromObj(interp, objv[i], getOptionStrings,
+		    "option", 0, &subIndex) != TCL_OK) {
+		return TCL_ERROR;
+	    }
+	    i++;
+	    if (i >= objc) {
+		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+			"value for \"%s\" missing", string));
+		Tcl_SetErrorCode(interp, "TK", "CLIPBOARD", "VALUE", NULL);
+		return TCL_ERROR;
+	    }
+	    switch ((enum getOptions) subIndex) {
+	    case APPEND_DISPLAYOF:
+		path = Tcl_GetString(objv[i]);
+		break;
+	    case APPEND_TYPE:
+		targetName = Tcl_GetString(objv[i]);
+		break;
+	    }
+	}
+	if (path != NULL) {
+	    tkwin = Tk_NameToWindow(interp, path, tkwin);
+	}
+	if (tkwin == NULL) {
+	    return TCL_ERROR;
+	}
+	selection = Tk_InternAtom(tkwin, "CLIPBOARD");
+
+	if (objc - i > 1) {
+	    Tcl_WrongNumArgs(interp, 2, objv, "?-option value ...?");
+	    return TCL_ERROR;
+	} else if (objc - i == 1) {
+	    target = Tk_InternAtom(tkwin, Tcl_GetString(objv[i]));
+	} else if (targetName != NULL) {
+	    target = Tk_InternAtom(tkwin, targetName);
+	} else {
+	    target = XA_STRING;
+	}
+
+	Tcl_DStringInit(&selBytes);
+	result = Tk_GetSelection(interp, tkwin, selection, target,
+		ClipboardGetProc, &selBytes);
+	if (result == TCL_OK) {
+	    Tcl_DStringResult(interp, &selBytes);
+	} else {
+	    Tcl_DStringFree(&selBytes);
+	}
+	return result;
+    }
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TkClipInit --
+ *
+ *	This function is called to initialize the window for claiming
+ *	clipboard ownership and for receiving selection get results. This
+ *	function is called from tkSelect.c as well as tkClipboard.c.
+ *
+ * Results:
+ *	The result is a standard Tcl return value, which is normally TCL_OK.
+ *	If an error occurs then an error message is left in the interp's
+ *	result and TCL_ERROR is returned.
+ *
+ * Side effects:
+ *	Sets up the clipWindow and related data structures.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TkClipInit(
+    Tcl_Interp *interp,		/* Interpreter to use for error reporting. */
+    register TkDisplay *dispPtr)/* Display to initialize. */
+{
+    XSetWindowAttributes atts;
+
+    dispPtr->clipTargetPtr = NULL;
+    dispPtr->clipboardActive = 0;
+    dispPtr->clipboardAppPtr = NULL;
+
+    /*
+     * Create the window used for clipboard ownership and selection retrieval,
+     * and set up an event handler for it.
+     */
+
+    dispPtr->clipWindow = (Tk_Window) TkAllocWindow(dispPtr,
+	DefaultScreen(dispPtr->display), NULL);
+    Tcl_Preserve(dispPtr->clipWindow);
+    ((TkWindow *) dispPtr->clipWindow)->flags |=
+	    TK_TOP_HIERARCHY|TK_TOP_LEVEL|TK_HAS_WRAPPER|TK_WIN_MANAGED;
+    TkWmNewWindow((TkWindow *) dispPtr->clipWindow);
+    atts.override_redirect = True;
+    Tk_ChangeWindowAttributes(dispPtr->clipWindow, CWOverrideRedirect, &atts);
+    Tk_MakeWindowExist(dispPtr->clipWindow);
+
+    if (dispPtr->multipleAtom == None) {
+	/*
+	 * Need to invoke selection initialization to make sure that atoms we
+	 * depend on below are defined.
+	 */
+
+	TkSelInit(dispPtr->clipWindow);
+    }
+
+    /*
+     * Create selection handlers for types TK_APPLICATION and TK_WINDOW on
+     * this window. Can't use the default handlers for these types because
+     * this isn't a full-fledged window.
+     */
+
+    Tk_CreateSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom,
+	    dispPtr->applicationAtom, ClipboardAppHandler, dispPtr,XA_STRING);
+    Tk_CreateSelHandler(dispPtr->clipWindow, dispPtr->clipboardAtom,
+	    dispPtr->windowAtom, ClipboardWindowHandler, dispPtr, XA_STRING);
+    return TCL_OK;
+}
+
+/*
+ *--------------------------------------------------------------
+ *
+ * ClipboardGetProc --
+ *
+ *	This function is invoked to process pieces of the selection as they
+ *	arrive during "clipboard get" commands.
+ *
+ * Results:
+ *	Always returns TCL_OK.
+ *
+ * Side effects:
+ *	Bytes get appended to the dynamic string pointed to by the clientData
+ *	argument.
+ *
+ *--------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ClipboardGetProc(
+    ClientData clientData,	/* Dynamic string holding partially assembled
+				 * selection. */
+    Tcl_Interp *interp,		/* Interpreter used for error reporting (not
+				 * used). */
+    const char *portion)	/* New information to be appended. */
+{
+    Tcl_DStringAppend((Tcl_DString *) clientData, portion, -1);
+    return TCL_OK;
+}
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */