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+# menu.tcl --
+#
+# This file defines the default bindings for Tk menus and menubuttons.
+# It also implements keyboard traversal of menus and implements a few
+# other utility procedures related to menus.
+#
+# SCCS: @(#) menu.tcl 1.103 97/10/31 15:26:08
+#
+# Copyright (c) 1992-1994 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.
+#
+
+#-------------------------------------------------------------------------
+# Elements of tkPriv that are used in this file:
+#
+# cursor -		Saves the -cursor option for the posted menubutton.
+# focus -		Saves the focus during a menu selection operation.
+#			Focus gets restored here when the menu is unposted.
+# grabGlobal -		Used in conjunction with tkPriv(oldGrab):  if
+#			tkPriv(oldGrab) is non-empty, then tkPriv(grabGlobal)
+#			contains either an empty string or "-global" to
+#			indicate whether the old grab was a local one or
+#			a global one.
+# inMenubutton -	The name of the menubutton widget containing
+#			the mouse, or an empty string if the mouse is
+#			not over any menubutton.
+# menuBar -		The name of the menubar that is the root
+#			of the cascade hierarchy which is currently
+#			posted. This is null when there is no menu currently
+#			being pulled down from a menu bar.
+# oldGrab -		Window that had the grab before a menu was posted.
+#			Used to restore the grab state after the menu
+#			is unposted.  Empty string means there was no
+#			grab previously set.
+# popup -		If a menu has been popped up via tk_popup, this
+#			gives the name of the menu.  Otherwise this
+#			value is empty.
+# postedMb -		Name of the menubutton whose menu is currently
+#			posted, or an empty string if nothing is posted
+#			A grab is set on this widget.
+# relief -		Used to save the original relief of the current
+#			menubutton.
+# window -		When the mouse is over a menu, this holds the
+#			name of the menu;  it's cleared when the mouse
+#			leaves the menu.
+# tearoff -		Whether the last menu posted was a tearoff or not.
+#			This is true always for unix, for tearoffs for Mac
+#			and Windows.
+# activeMenu -		This is the last active menu for use
+#			with the <<MenuSelect>> virtual event.
+# activeItem -		This is the last active menu item for
+#			use with the <<MenuSelect>> virtual event.
+#-------------------------------------------------------------------------
+
+#-------------------------------------------------------------------------
+# Overall note:
+# This file is tricky because there are five different ways that menus
+# can be used:
+#
+# 1. As a pulldown from a menubutton. In this style, the variable 
+#    tkPriv(postedMb) identifies the posted menubutton.
+# 2. As a torn-off menu copied from some other menu.  In this style
+#    tkPriv(postedMb) is empty, and menu's type is "tearoff".
+# 3. As an option menu, triggered from an option menubutton.  In this
+#    style tkPriv(postedMb) identifies the posted menubutton.
+# 4. As a popup menu.  In this style tkPriv(postedMb) is empty and
+#    the top-level menu's type is "normal".
+# 5. As a pulldown from a menubar. The variable tkPriv(menubar) has
+#    the owning menubar, and the menu itself is of type "normal".
+#
+# The various binding procedures use the  state described above to
+# distinguish the various cases and take different actions in each
+# case.
+#-------------------------------------------------------------------------
+
+#-------------------------------------------------------------------------
+# The code below creates the default class bindings for menus
+# and menubuttons.
+#-------------------------------------------------------------------------
+
+bind Menubutton <FocusIn> {}
+bind Menubutton <Enter> {
+    tkMbEnter %W
+}
+bind Menubutton <Leave> {
+    tkMbLeave %W
+}
+bind Menubutton <1> {
+    if {$tkPriv(inMenubutton) != ""} {
+	tkMbPost $tkPriv(inMenubutton) %X %Y
+    }
+}
+bind Menubutton <Motion> {
+    tkMbMotion %W up %X %Y
+}
+bind Menubutton <B1-Motion> {
+    tkMbMotion %W down %X %Y
+}
+bind Menubutton <ButtonRelease-1> {
+    tkMbButtonUp %W
+}
+bind Menubutton <space> {
+    tkMbPost %W
+    tkMenuFirstEntry [%W cget -menu]
+}
+
+# Must set focus when mouse enters a menu, in order to allow
+# mixed-mode processing using both the mouse and the keyboard.
+# Don't set the focus if the event comes from a grab release,
+# though:  such an event can happen after as part of unposting
+# a cascaded chain of menus, after the focus has already been
+# restored to wherever it was before menu selection started.
+
+bind Menu <FocusIn> {}
+
+bind Menu <Enter> {
+    set tkPriv(window) %W
+    if {[%W cget -type] == "tearoff"} {
+	if {"%m" != "NotifyUngrab"} {
+	    if {$tcl_platform(platform) == "unix"} {
+		tk_menuSetFocus %W
+	    }
+	}
+    }
+    tkMenuMotion %W %x %y %s
+}
+
+bind Menu <Leave> {
+    tkMenuLeave %W %X %Y %s
+}
+bind Menu <Motion> {
+    tkMenuMotion %W %x %y %s
+}
+bind Menu <ButtonPress> {
+    tkMenuButtonDown %W
+}
+bind Menu <ButtonRelease> {
+   tkMenuInvoke %W 1
+}
+bind Menu <space> {
+    tkMenuInvoke %W 0
+}
+bind Menu <Return> {
+    tkMenuInvoke %W 0
+}
+bind Menu <Escape> {
+    tkMenuEscape %W
+}
+bind Menu <Left> {
+    tkMenuLeftArrow %W
+}
+bind Menu <Right> {
+    tkMenuRightArrow %W
+}
+bind Menu <Up> {
+    tkMenuUpArrow %W
+}
+bind Menu <Down> {
+    tkMenuDownArrow %W
+}
+bind Menu <KeyPress> {
+    tkTraverseWithinMenu %W %A
+}
+
+# The following bindings apply to all windows, and are used to
+# implement keyboard menu traversal.
+
+if {$tcl_platform(platform) == "unix"} {
+    bind all <Alt-KeyPress> {
+	tkTraverseToMenu %W %A
+    }
+
+    bind all <F10> {
+	tkFirstMenu %W
+    }
+} else {
+    bind Menubutton <Alt-KeyPress> {
+	tkTraverseToMenu %W %A
+    }
+
+    bind Menubutton <F10> {
+	tkFirstMenu %W
+    }
+}
+
+# tkMbEnter --
+# This procedure is invoked when the mouse enters a menubutton
+# widget.  It activates the widget unless it is disabled.  Note:
+# this procedure is only invoked when mouse button 1 is *not* down.
+# The procedure tkMbB1Enter is invoked if the button is down.
+#
+# Arguments:
+# w -			The  name of the widget.
+
+proc tkMbEnter w {
+    global tkPriv
+
+    if {$tkPriv(inMenubutton) != ""} {
+	tkMbLeave $tkPriv(inMenubutton)
+    }
+    set tkPriv(inMenubutton) $w
+    if {[$w cget -state] != "disabled"} {
+	$w configure -state active
+    }
+}
+
+# tkMbLeave --
+# This procedure is invoked when the mouse leaves a menubutton widget.
+# It de-activates the widget, if the widget still exists.
+#
+# Arguments:
+# w -			The  name of the widget.
+
+proc tkMbLeave w {
+    global tkPriv
+
+    set tkPriv(inMenubutton) {}
+    if ![winfo exists $w] {
+	return
+    }
+    if {[$w cget -state] == "active"} {
+	$w configure -state normal
+    }
+}
+
+# tkMbPost --
+# Given a menubutton, this procedure does all the work of posting
+# its associated menu and unposting any other menu that is currently
+# posted.
+#
+# Arguments:
+# w -			The name of the menubutton widget whose menu
+#			is to be posted.
+# x, y -		Root coordinates of cursor, used for positioning
+#			option menus.  If not specified, then the center
+#			of the menubutton is used for an option menu.
+
+proc tkMbPost {w {x {}} {y {}}} {
+    global tkPriv errorInfo
+    global tcl_platform
+
+    if {([$w cget -state] == "disabled") || ($w == $tkPriv(postedMb))} {
+	return
+    }
+    set menu [$w cget -menu]
+    if {$menu == ""} {
+	return
+    }
+    set tearoff [expr {($tcl_platform(platform) == "unix") \
+		     || ([$menu cget -type] == "tearoff")}]
+    if {[string first $w $menu] != 0} {
+	error "can't post $menu:  it isn't a descendant of $w (this is a new requirement in Tk versions 3.0 and later)"
+    }
+    set cur $tkPriv(postedMb)
+    if {$cur != ""} {
+	tkMenuUnpost {}
+    }
+    set tkPriv(cursor) [$w cget -cursor]
+    set tkPriv(relief) [$w cget -relief]
+    $w configure -cursor arrow
+    $w configure -relief raised
+
+    set tkPriv(postedMb) $w
+    set tkPriv(focus) [focus]
+    $menu activate none
+    tkGenerateMenuSelect $menu
+
+    # If this looks like an option menubutton then post the menu so
+    # that the current entry is on top of the mouse.  Otherwise post
+    # the menu just below the menubutton, as for a pull-down.
+
+    update idletasks
+    if [catch {
+    	 switch [$w cget -direction] {
+    	    above {
+    	    	set x [winfo rootx $w]
+    	    	set y [expr [winfo rooty $w] - [winfo reqheight $menu]]
+    	    	$menu post $x $y
+    	    }
+    	    below {
+    	    	set x [winfo rootx $w]
+    	    	set y [expr [winfo rooty $w] + [winfo height $w]]
+    	    	$menu post $x $y
+    	    }
+    	    left {
+    	    	set x [expr [winfo rootx $w] - [winfo reqwidth $menu]]
+    	    	set y [expr (2 * [winfo rooty $w] + [winfo height $w]) / 2]
+    	    	set entry [tkMenuFindName $menu [$w cget -text]]
+    	    	if [$w cget -indicatoron] {
+		    if {$entry == [$menu index last]} {
+		    	incr y [expr -([$menu yposition $entry] \
+			    	+ [winfo reqheight $menu])/2]
+		    } else {
+		    	incr y [expr -([$menu yposition $entry] \
+			        + [$menu yposition [expr $entry+1]])/2]
+		    }
+    	    	}
+    	    	$menu post $x $y
+    	    	if {($entry != {}) && ([$menu entrycget $entry -state] != "disabled")} {
+    	    	    $menu activate $entry
+		    tkGenerateMenuSelect $menu
+    	    	}
+    	    }
+    	    right {
+    	    	set x [expr [winfo rootx $w] + [winfo width $w]]
+    	    	set y [expr (2 * [winfo rooty $w] + [winfo height $w]) / 2]
+    	    	set entry [tkMenuFindName $menu [$w cget -text]]
+    	    	if [$w cget -indicatoron] {
+		    if {$entry == [$menu index last]} {
+		    	incr y [expr -([$menu yposition $entry] \
+			    	+ [winfo reqheight $menu])/2]
+		    } else {
+		    	incr y [expr -([$menu yposition $entry] \
+			        + [$menu yposition [expr $entry+1]])/2]
+		    }
+    	    	}
+    	    	$menu post $x $y
+    	    	if {($entry != {}) && ([$menu entrycget $entry -state] != "disabled")} {
+    	    	    $menu activate $entry
+		    tkGenerateMenuSelect $menu
+    	    	}
+    	    }
+    	    default {
+    	    	if [$w cget -indicatoron] {
+	    	    if {$y == ""} {
+			set x [expr [winfo rootx $w] + [winfo width $w]/2]
+			set y [expr [winfo rooty $w] + [winfo height $w]/2]
+	    	    }
+	            tkPostOverPoint $menu $x $y [tkMenuFindName $menu [$w cget -text]]
+		} else {
+	    	    $menu post [winfo rootx $w] [expr [winfo rooty $w]+[winfo height $w]]
+    	    	}  
+    	    }
+    	 }
+     } msg] {
+	# Error posting menu (e.g. bogus -postcommand). Unpost it and
+	# reflect the error.
+	
+	set savedInfo $errorInfo
+	tkMenuUnpost {}
+	error $msg $savedInfo
+
+    }
+
+    set tkPriv(tearoff) $tearoff
+    if {$tearoff != 0} {
+    	focus $menu
+    	tkSaveGrabInfo $w
+    	grab -global $w
+    }
+}
+
+# tkMenuUnpost --
+# This procedure unposts a given menu, plus all of its ancestors up
+# to (and including) a menubutton, if any.  It also restores various
+# values to what they were before the menu was posted, and releases
+# a grab if there's a menubutton involved.  Special notes:
+# 1. It's important to unpost all menus before releasing the grab, so
+#    that any Enter-Leave events (e.g. from menu back to main
+#    application) have mode NotifyGrab.
+# 2. Be sure to enclose various groups of commands in "catch" so that
+#    the procedure will complete even if the menubutton or the menu
+#    or the grab window has been deleted.
+#
+# Arguments:
+# menu -		Name of a menu to unpost.  Ignored if there
+#			is a posted menubutton.
+
+proc tkMenuUnpost menu {
+    global tcl_platform
+    global tkPriv
+    set mb $tkPriv(postedMb)
+
+    # Restore focus right away (otherwise X will take focus away when
+    # the menu is unmapped and under some window managers (e.g. olvwm)
+    # we'll lose the focus completely).
+
+    catch {focus $tkPriv(focus)}
+    set tkPriv(focus) ""
+
+    # Unpost menu(s) and restore some stuff that's dependent on
+    # what was posted.
+
+    catch {
+	if {$mb != ""} {
+	    set menu [$mb cget -menu]
+	    $menu unpost
+	    set tkPriv(postedMb) {}
+	    $mb configure -cursor $tkPriv(cursor)
+	    $mb configure -relief $tkPriv(relief)
+	} elseif {$tkPriv(popup) != ""} {
+	    $tkPriv(popup) unpost
+	    set tkPriv(popup) {}
+	} elseif {(!([$menu cget -type] == "menubar")
+		&& !([$menu cget -type] == "tearoff"))} {
+	    # We're in a cascaded sub-menu from a torn-off menu or popup.
+	    # Unpost all the menus up to the toplevel one (but not
+	    # including the top-level torn-off one) and deactivate the
+	    # top-level torn off menu if there is one.
+
+	    while 1 {
+		set parent [winfo parent $menu]
+		if {([winfo class $parent] != "Menu")
+			|| ![winfo ismapped $parent]} {
+		    break
+		}
+		$parent activate none
+		$parent postcascade none
+		tkGenerateMenuSelect $parent
+		set type [$parent cget -type]
+		if {($type == "menubar")|| ($type == "tearoff")} {
+		    break
+		}
+		set menu $parent
+	    }
+	    if {[$menu cget -type] != "menubar"} {
+		$menu unpost
+	    }
+	}
+    }
+
+    if {($tkPriv(tearoff) != 0) || ($tkPriv(menuBar) != "")} {
+    	# Release grab, if any, and restore the previous grab, if there
+    	# was one.
+
+	if {$menu != ""} {
+	    set grab [grab current $menu]
+	    if {$grab != ""} {
+		grab release $grab
+	    }
+	}
+	tkRestoreOldGrab
+	if {$tkPriv(menuBar) != ""} {
+	    $tkPriv(menuBar) configure -cursor $tkPriv(cursor)
+	    set tkPriv(menuBar) {}
+	}
+	if {$tcl_platform(platform) != "unix"} {
+	    set tkPriv(tearoff) 0
+	}
+    }
+}
+
+# tkMbMotion --
+# This procedure handles mouse motion events inside menubuttons, and
+# also outside menubuttons when a menubutton has a grab (e.g. when a
+# menu selection operation is in progress).
+#
+# Arguments:
+# w -			The name of the menubutton widget.
+# upDown - 		"down" means button 1 is pressed, "up" means
+#			it isn't.
+# rootx, rooty -	Coordinates of mouse, in (virtual?) root window.
+
+proc tkMbMotion {w upDown rootx rooty} {
+    global tkPriv
+
+    if {$tkPriv(inMenubutton) == $w} {
+	return
+    }
+    set new [winfo containing $rootx $rooty]
+    if {($new != $tkPriv(inMenubutton)) && (($new == "")
+	    || ([winfo toplevel $new] == [winfo toplevel $w]))} {
+	if {$tkPriv(inMenubutton) != ""} {
+	    tkMbLeave $tkPriv(inMenubutton)
+	}
+	if {($new != "") && ([winfo class $new] == "Menubutton")
+		&& ([$new cget -indicatoron] == 0)
+		&& ([$w cget -indicatoron] == 0)} {
+	    if {$upDown == "down"} {
+		tkMbPost $new $rootx $rooty
+	    } else {
+		tkMbEnter $new
+	    }
+	}
+    }
+}
+
+# tkMbButtonUp --
+# This procedure is invoked to handle button 1 releases for menubuttons.
+# If the release happens inside the menubutton then leave its menu
+# posted with element 0 activated.  Otherwise, unpost the menu.
+#
+# Arguments:
+# w -			The name of the menubutton widget.
+
+proc tkMbButtonUp w {
+    global tkPriv
+    global tcl_platform
+
+    set tearoff [expr {($tcl_platform(platform) == "unix") \
+		     || ([[$w cget -menu] cget -type] == "tearoff")}]
+    if {($tearoff != 0) && ($tkPriv(postedMb) == $w) 
+	    && ($tkPriv(inMenubutton) == $w)} {
+	tkMenuFirstEntry [$tkPriv(postedMb) cget -menu]
+    } else {
+	tkMenuUnpost {}
+    }
+}
+
+# tkMenuMotion --
+# This procedure is called to handle mouse motion events for menus.
+# It does two things.  First, it resets the active element in the
+# menu, if the mouse is over the menu.  Second, if a mouse button
+# is down, it posts and unposts cascade entries to match the mouse
+# position.
+#
+# Arguments:
+# menu -		The menu window.
+# x -			The x position of the mouse.
+# y -			The y position of the mouse.
+# state -		Modifier state (tells whether buttons are down).
+
+proc tkMenuMotion {menu x y state} {
+    global tkPriv
+    if {$menu == $tkPriv(window)} {
+	if {[$menu cget -type] == "menubar"} {
+	    if {[info exists tkPriv(focus)] && \
+		    ([string compare $menu $tkPriv(focus)] != 0)} {
+		$menu activate @$x,$y
+		tkGenerateMenuSelect $menu
+	    }
+	} else {
+	    $menu activate @$x,$y
+	    tkGenerateMenuSelect $menu
+	}
+    }
+    if {($state & 0x1f00) != 0} {
+	$menu postcascade active
+    }
+}
+
+# tkMenuButtonDown --
+# Handles button presses in menus.  There are a couple of tricky things
+# here:
+# 1. Change the posted cascade entry (if any) to match the mouse position.
+# 2. If there is a posted menubutton, must grab to the menubutton;  this
+#    overrrides the implicit grab on button press, so that the menu
+#    button can track mouse motions over other menubuttons and change
+#    the posted menu.
+# 3. If there's no posted menubutton (e.g. because we're a torn-off menu
+#    or one of its descendants) must grab to the top-level menu so that
+#    we can track mouse motions across the entire menu hierarchy.
+#
+# Arguments:
+# menu -		The menu window.
+
+proc tkMenuButtonDown menu {
+    global tkPriv
+    global tcl_platform
+    $menu postcascade active
+    if {$tkPriv(postedMb) != ""} {
+	grab -global $tkPriv(postedMb)
+    } else {
+	while {([$menu cget -type] == "normal") 
+		&& ([winfo class [winfo parent $menu]] == "Menu")
+		&& [winfo ismapped [winfo parent $menu]]} {
+	    set menu [winfo parent $menu]
+	}
+
+	if {$tkPriv(menuBar) == {}} {
+	    set tkPriv(menuBar) $menu
+	    set tkPriv(cursor) [$menu cget -cursor]
+	    $menu configure -cursor arrow
+        }
+
+	# Don't update grab information if the grab window isn't changing.
+	# Otherwise, we'll get an error when we unpost the menus and
+	# restore the grab, since the old grab window will not be viewable
+	# anymore.
+
+	if {$menu != [grab current $menu]} {
+	    tkSaveGrabInfo $menu
+	}
+
+	# Must re-grab even if the grab window hasn't changed, in order
+	# to release the implicit grab from the button press.
+
+	if {$tcl_platform(platform) == "unix"} {
+	    grab -global $menu
+	}
+    }
+}
+
+# tkMenuLeave --
+# This procedure is invoked to handle Leave events for a menu.  It
+# deactivates everything unless the active element is a cascade element
+# and the mouse is now over the submenu.
+#
+# Arguments:
+# menu -		The menu window.
+# rootx, rooty -	Root coordinates of mouse.
+# state -		Modifier state.
+
+proc tkMenuLeave {menu rootx rooty state} {
+    global tkPriv
+    set tkPriv(window) {}
+    if {[$menu index active] == "none"} {
+	return
+    }
+    if {([$menu type active] == "cascade")
+	    && ([winfo containing $rootx $rooty]
+	    == [$menu entrycget active -menu])} {
+	return
+    }
+    $menu activate none
+    tkGenerateMenuSelect $menu
+}
+
+# tkMenuInvoke --
+# This procedure is invoked when button 1 is released over a menu.
+# It invokes the appropriate menu action and unposts the menu if
+# it came from a menubutton.
+#
+# Arguments:
+# w -			Name of the menu widget.
+# buttonRelease -	1 means this procedure is called because of
+#			a button release;  0 means because of keystroke.
+
+proc tkMenuInvoke {w buttonRelease} {
+    global tkPriv
+
+    if {$buttonRelease && ($tkPriv(window) == "")} {
+	# Mouse was pressed over a menu without a menu button, then
+	# dragged off the menu (possibly with a cascade posted) and
+	# released.  Unpost everything and quit.
+
+	$w postcascade none
+	$w activate none
+	event generate $w <<MenuSelect>>
+	tkMenuUnpost $w
+	return
+    }
+    if {[$w type active] == "cascade"} {
+	$w postcascade active
+	set menu [$w entrycget active -menu]
+	tkMenuFirstEntry $menu
+    } elseif {[$w type active] == "tearoff"} {
+	tkMenuUnpost $w
+	tkTearOffMenu $w
+    } elseif {[$w cget -type] == "menubar"} {
+	$w postcascade none
+	$w activate none
+	event generate $w <<MenuSelect>>
+	tkMenuUnpost $w
+    } else {
+	tkMenuUnpost $w
+	uplevel #0 [list $w invoke active]
+    }
+}
+
+# tkMenuEscape --
+# This procedure is invoked for the Cancel (or Escape) key.  It unposts
+# the given menu and, if it is the top-level menu for a menu button,
+# unposts the menu button as well.
+#
+# Arguments:
+# menu -		Name of the menu window.
+
+proc tkMenuEscape menu {
+    set parent [winfo parent $menu]
+    if {([winfo class $parent] != "Menu")} {
+	tkMenuUnpost $menu
+    } elseif {([$parent cget -type] == "menubar")} {
+	tkMenuUnpost $menu
+	tkRestoreOldGrab
+    } else {
+	tkMenuNextMenu $menu left
+    }
+}
+
+# The following routines handle arrow keys. Arrow keys behave
+# differently depending on whether the menu is a menu bar or not.
+
+proc tkMenuUpArrow {menu} {
+    if {[$menu cget -type] == "menubar"} {
+	tkMenuNextMenu $menu left
+    } else {
+	tkMenuNextEntry $menu -1
+    }
+}
+
+proc tkMenuDownArrow {menu} {
+    if {[$menu cget -type] == "menubar"} {
+	tkMenuNextMenu $menu right
+    } else {
+	tkMenuNextEntry $menu 1
+    }
+}
+
+proc tkMenuLeftArrow {menu} {
+    if {[$menu cget -type] == "menubar"} {
+	tkMenuNextEntry $menu -1
+    } else {
+	tkMenuNextMenu $menu left
+    }
+}
+
+proc tkMenuRightArrow {menu} {
+    if {[$menu cget -type] == "menubar"} {
+	tkMenuNextEntry $menu 1
+    } else {
+	tkMenuNextMenu $menu right
+    }
+}
+
+# tkMenuNextMenu --
+# This procedure is invoked to handle "left" and "right" traversal
+# motions in menus.  It traverses to the next menu in a menu bar,
+# or into or out of a cascaded menu.
+#
+# Arguments:
+# menu -		The menu that received the keyboard
+#			event.
+# direction -		Direction in which to move: "left" or "right"
+
+proc tkMenuNextMenu {menu direction} {
+    global tkPriv
+
+    # First handle traversals into and out of cascaded menus.
+
+    if {$direction == "right"} {
+	set count 1
+	set parent [winfo parent $menu]
+	set class [winfo class $parent]
+	if {[$menu type active] == "cascade"} {
+	    $menu postcascade active
+	    set m2 [$menu entrycget active -menu]
+	    if {$m2 != ""} {
+		tkMenuFirstEntry $m2
+	    }
+	    return
+	} else {
+	    set parent [winfo parent $menu]
+	    while {($parent != ".")} {
+		if {([winfo class $parent] == "Menu")
+			&& ([$parent cget -type] == "menubar")} {
+		    tk_menuSetFocus $parent
+		    tkMenuNextEntry $parent 1
+		    return
+		}
+		set parent [winfo parent $parent]
+	    }
+	}
+    } else {
+	set count -1
+	set m2 [winfo parent $menu]
+	if {[winfo class $m2] == "Menu"} {
+	    if {[$m2 cget -type] != "menubar"} {
+		$menu activate none
+		tkGenerateMenuSelect $menu
+		tk_menuSetFocus $m2
+		
+		# This code unposts any posted submenu in the parent.
+		
+		set tmp [$m2 index active]
+		$m2 activate none
+		$m2 activate $tmp
+		return
+	    }
+	}
+    }
+
+    # Can't traverse into or out of a cascaded menu.  Go to the next
+    # or previous menubutton, if that makes sense.
+
+    set m2 [winfo parent $menu]
+    if {[winfo class $m2] == "Menu"} {
+	if {[$m2 cget -type] == "menubar"} {
+	    tk_menuSetFocus $m2
+	    tkMenuNextEntry $m2 -1
+	    return
+	}
+    }
+
+    set w $tkPriv(postedMb)
+    if {$w == ""} {
+	return
+    }
+    set buttons [winfo children [winfo parent $w]]
+    set length [llength $buttons]
+    set i [expr [lsearch -exact $buttons $w] + $count]
+    while 1 {
+	while {$i < 0} {
+	    incr i $length
+	}
+	while {$i >= $length} {
+	    incr i -$length
+	}
+	set mb [lindex $buttons $i]
+	if {([winfo class $mb] == "Menubutton")
+		&& ([$mb cget -state] != "disabled")
+		&& ([$mb cget -menu] != "")
+		&& ([[$mb cget -menu] index last] != "none")} {
+	    break
+	}
+	if {$mb == $w} {
+	    return
+	}
+	incr i $count
+    }
+    tkMbPost $mb
+    tkMenuFirstEntry [$mb cget -menu]
+}
+
+# tkMenuNextEntry --
+# Activate the next higher or lower entry in the posted menu,
+# wrapping around at the ends.  Disabled entries are skipped.
+#
+# Arguments:
+# menu -			Menu window that received the keystroke.
+# count -			1 means go to the next lower entry,
+#				-1 means go to the next higher entry.
+
+proc tkMenuNextEntry {menu count} {
+    global tkPriv
+
+    if {[$menu index last] == "none"} {
+	return
+    }
+    set length [expr [$menu index last]+1]
+    set quitAfter $length
+    set active [$menu index active]
+    if {$active == "none"} {
+	set i 0
+    } else {
+	set i [expr $active + $count]
+    }
+    while 1 {
+	if {$quitAfter <= 0} {
+	    # We've tried every entry in the menu.  Either there are
+	    # none, or they're all disabled.  Just give up.
+
+	    return
+	}
+	while {$i < 0} {
+	    incr i $length
+	}
+	while {$i >= $length} {
+	    incr i -$length
+	}
+	if {[catch {$menu entrycget $i -state} state] == 0} {
+	    if {$state != "disabled"} {
+		break
+	    }
+	}
+	if {$i == $active} {
+	    return
+	}
+	incr i $count
+	incr quitAfter -1
+    }
+    $menu activate $i
+    tkGenerateMenuSelect $menu
+    if {[$menu type $i] == "cascade"} {
+	set cascade [$menu entrycget $i -menu]
+	if {[string compare $cascade ""] != 0} {
+	    $menu postcascade $i
+	    tkMenuFirstEntry $cascade
+	}
+    }
+}
+
+# tkMenuFind --
+# This procedure searches the entire window hierarchy under w for
+# a menubutton that isn't disabled and whose underlined character
+# is "char" or an entry in a menubar that isn't disabled and whose
+# underlined character is "char".
+# It returns the name of that window, if found, or an
+# empty string if no matching window was found.  If "char" is an
+# empty string then the procedure returns the name of the first
+# menubutton found that isn't disabled.
+#
+# Arguments:
+# w -				Name of window where key was typed.
+# char -			Underlined character to search for;
+#				may be either upper or lower case, and
+#				will match either upper or lower case.
+
+proc tkMenuFind {w char} {
+    global tkPriv
+    set char [string tolower $char]
+    set windowlist [winfo child $w]
+
+    foreach child $windowlist {
+	switch [winfo class $child] {
+	    Menu {
+		if {[$child cget -type] == "menubar"} {
+		    if {$char == ""} {
+			return $child
+		    }
+		    set last [$child index last]
+		    for {set i [$child cget -tearoff]} {$i <= $last} {incr i} {
+			if {[$child type $i] == "separator"} {
+			    continue
+			}
+			set char2 [string index [$child entrycget $i -label] \
+				[$child entrycget $i -underline]]
+			if {([string compare $char [string tolower $char2]] \
+				== 0) || ($char == "")} {
+			    if {[$child entrycget $i -state] != "disabled"} {
+				return $child
+			    }
+			}
+		    }
+		}
+	    }
+	}
+    }
+
+    foreach child $windowlist {
+	switch [winfo class $child] {
+	    Menubutton {
+		set char2 [string index [$child cget -text] \
+			[$child cget -underline]]
+		if {([string compare $char [string tolower $char2]] == 0)
+			|| ($char == "")} {
+		    if {[$child cget -state] != "disabled"} {
+			return $child
+		    }
+		}
+	    }
+
+	    default {
+		set match [tkMenuFind $child $char]
+		if {$match != ""} {
+		    return $match
+		}
+	    }
+	}
+    }
+    return {}
+}
+
+# tkTraverseToMenu --
+# This procedure implements keyboard traversal of menus.  Given an
+# ASCII character "char", it looks for a menubutton with that character
+# underlined.  If one is found, it posts the menubutton's menu
+#
+# Arguments:
+# w -				Window in which the key was typed (selects
+#				a toplevel window).
+# char -			Character that selects a menu.  The case
+#				is ignored.  If an empty string, nothing
+#				happens.
+
+proc tkTraverseToMenu {w char} {
+    global tkPriv
+    if {$char == ""} {
+	return
+    }
+    while {[winfo class $w] == "Menu"} {
+	if {([$w cget -type] != "menubar") && ($tkPriv(postedMb) == "")} {
+	    return
+	}
+	if {[$w cget -type] == "menubar"} {
+	    break
+	}
+	set w [winfo parent $w]
+    }
+    set w [tkMenuFind [winfo toplevel $w] $char]
+    if {$w != ""} {
+	if {[winfo class $w] == "Menu"} {
+	    tk_menuSetFocus $w
+	    set tkPriv(window) $w
+	    tkSaveGrabInfo $w
+	    grab -global $w
+	    tkTraverseWithinMenu $w $char
+	} else {
+	    tkMbPost $w
+	    tkMenuFirstEntry [$w cget -menu]
+	}
+    }
+}
+
+# tkFirstMenu --
+# This procedure traverses to the first menubutton in the toplevel
+# for a given window, and posts that menubutton's menu.
+#
+# Arguments:
+# w -				Name of a window.  Selects which toplevel
+#				to search for menubuttons.
+
+proc tkFirstMenu w {
+    set w [tkMenuFind [winfo toplevel $w] ""]
+    if {$w != ""} {
+	if {[winfo class $w] == "Menu"} {
+	    tk_menuSetFocus $w
+	    set tkPriv(window) $w
+	    tkSaveGrabInfo $w
+	    grab -global $w
+	    tkMenuFirstEntry $w
+	} else {
+	    tkMbPost $w
+	    tkMenuFirstEntry [$w cget -menu]
+	}
+    }
+}
+
+# tkTraverseWithinMenu
+# This procedure implements keyboard traversal within a menu.  It
+# searches for an entry in the menu that has "char" underlined.  If
+# such an entry is found, it is invoked and the menu is unposted.
+#
+# Arguments:
+# w -				The name of the menu widget.
+# char -			The character to look for;  case is
+#				ignored.  If the string is empty then
+#				nothing happens.
+
+proc tkTraverseWithinMenu {w char} {
+    if {$char == ""} {
+	return
+    }
+    set char [string tolower $char]
+    set last [$w index last]
+    if {$last == "none"} {
+	return
+    }
+    for {set i 0} {$i <= $last} {incr i} {
+	if [catch {set char2 [string index \
+		[$w entrycget $i -label] \
+		[$w entrycget $i -underline]]}] {
+	    continue
+	}
+	if {[string compare $char [string tolower $char2]] == 0} {
+	    if {[$w type $i] == "cascade"} {
+		$w activate $i
+		$w postcascade active
+		event generate $w <<MenuSelect>>
+		set m2 [$w entrycget $i -menu]
+		if {$m2 != ""} {
+		    tkMenuFirstEntry $m2
+		}
+	    } else {
+		tkMenuUnpost $w
+		uplevel #0 [list $w invoke $i]
+	    }
+	    return
+	}
+    }
+}
+
+# tkMenuFirstEntry --
+# Given a menu, this procedure finds the first entry that isn't
+# disabled or a tear-off or separator, and activates that entry.
+# However, if there is already an active entry in the menu (e.g.,
+# because of a previous call to tkPostOverPoint) then the active
+# entry isn't changed.  This procedure also sets the input focus
+# to the menu.
+#
+# Arguments:
+# menu -		Name of the menu window (possibly empty).
+
+proc tkMenuFirstEntry menu {
+    if {$menu == ""} {
+	return
+    }
+    tk_menuSetFocus $menu
+    if {[$menu index active] != "none"} {
+	return
+    }
+    set last [$menu index last]
+    if {$last == "none"} {
+	return
+    }
+    for {set i 0} {$i <= $last} {incr i} {
+	if {([catch {set state [$menu entrycget $i -state]}] == 0)
+		&& ($state != "disabled") && ([$menu type $i] != "tearoff")} {
+	    $menu activate $i
+	    tkGenerateMenuSelect $menu
+	    if {[$menu type $i] == "cascade"} {
+		set cascade [$menu entrycget $i -menu]
+		if {[string compare $cascade ""] != 0} {
+		    $menu postcascade $i
+		    tkMenuFirstEntry $cascade
+		}
+	    }
+	    return
+	}
+    }
+}
+
+# tkMenuFindName --
+# Given a menu and a text string, return the index of the menu entry
+# that displays the string as its label.  If there is no such entry,
+# return an empty string.  This procedure is tricky because some names
+# like "active" have a special meaning in menu commands, so we can't
+# always use the "index" widget command.
+#
+# Arguments:
+# menu -		Name of the menu widget.
+# s -			String to look for.
+
+proc tkMenuFindName {menu s} {
+    set i ""
+    if {![regexp {^active$|^last$|^none$|^[0-9]|^@} $s]} {
+	catch {set i [$menu index $s]}
+	return $i
+    }
+    set last [$menu index last]
+    if {$last == "none"} {
+	return
+    }
+    for {set i 0} {$i <= $last} {incr i} {
+	if ![catch {$menu entrycget $i -label} label] {
+	    if {$label == $s} {
+		return $i
+	    }
+	}
+    }
+    return ""
+}
+
+# tkPostOverPoint --
+# This procedure posts a given menu such that a given entry in the
+# menu is centered over a given point in the root window.  It also
+# activates the given entry.
+#
+# Arguments:
+# menu -		Menu to post.
+# x, y -		Root coordinates of point.
+# entry -		Index of entry within menu to center over (x,y).
+#			If omitted or specified as {}, then the menu's
+#			upper-left corner goes at (x,y).
+
+proc tkPostOverPoint {menu x y {entry {}}}  {
+    global tcl_platform
+    
+    if {$entry != {}} {
+	if {$entry == [$menu index last]} {
+	    incr y [expr -([$menu yposition $entry] \
+		    + [winfo reqheight $menu])/2]
+	} else {
+	    incr y [expr -([$menu yposition $entry] \
+		    + [$menu yposition [expr $entry+1]])/2]
+	}
+	incr x [expr -[winfo reqwidth $menu]/2]
+    }
+    $menu post $x $y
+    if {($entry != {}) && ([$menu entrycget $entry -state] != "disabled")} {
+	$menu activate $entry
+	tkGenerateMenuSelect $menu
+    }
+}
+
+# tkSaveGrabInfo --
+# Sets the variables tkPriv(oldGrab) and tkPriv(grabStatus) to record
+# the state of any existing grab on the w's display.
+#
+# Arguments:
+# w -			Name of a window;  used to select the display
+#			whose grab information is to be recorded.
+
+proc tkSaveGrabInfo w {
+    global tkPriv
+    set tkPriv(oldGrab) [grab current $w]
+    if {$tkPriv(oldGrab) != ""} {
+	set tkPriv(grabStatus) [grab status $tkPriv(oldGrab)]
+    }
+}
+
+# tkRestoreOldGrab --
+# Restores the grab to what it was before TkSaveGrabInfo was called.
+#
+
+proc tkRestoreOldGrab {} {
+    global tkPriv
+
+    if {$tkPriv(oldGrab) != ""} {
+
+    	# Be careful restoring the old grab, since it's window may not
+	# be visible anymore.
+
+	catch {
+	    if {$tkPriv(grabStatus) == "global"} {
+		grab set -global $tkPriv(oldGrab)
+	    } else {
+		grab set $tkPriv(oldGrab)
+	    }
+	}
+	set tkPriv(oldGrab) ""
+    }
+}
+
+proc tk_menuSetFocus {menu} {
+    global tkPriv
+    if {![info exists tkPriv(focus)] || [string length $tkPriv(focus)] == 0} {
+	set tkPriv(focus) [focus]
+    }
+    focus $menu
+}
+    
+proc tkGenerateMenuSelect {menu} {
+    global tkPriv
+
+    if {([string compare $tkPriv(activeMenu) $menu] == 0) \
+	    && ([string compare $tkPriv(activeItem) [$menu index active]] \
+	    == 0)} {
+	return
+    }
+
+    set tkPriv(activeMenu) $menu
+    set tkPriv(activeItem) [$menu index active]
+    event generate $menu <<MenuSelect>>
+}
+
+# tk_popup --
+# This procedure pops up a menu and sets things up for traversing
+# the menu and its submenus.
+#
+# Arguments:
+# menu -		Name of the menu to be popped up.
+# x, y -		Root coordinates at which to pop up the
+#			menu.
+# entry -		Index of a menu entry to center over (x,y).
+#			If omitted or specified as {}, then menu's
+#			upper-left corner goes at (x,y).
+
+proc tk_popup {menu x y {entry {}}} {
+    global tkPriv
+    global tcl_platform
+    if {($tkPriv(popup) != "") || ($tkPriv(postedMb) != "")} {
+	tkMenuUnpost {}
+    }
+    tkPostOverPoint $menu $x $y $entry
+    if {$tcl_platform(platform) == "unix"} {
+	tkSaveGrabInfo $menu
+	grab -global $menu
+	set tkPriv(popup) $menu
+	tk_menuSetFocus $menu
+    }
+}