@c This is part of the Emacs manual. @c Copyright (C) 1985, 86, 87, 93, 94, 95, 97, 99, 2000, 2001 @c Free Software Foundation, Inc. @c See file emacs.texi for copying conditions. @node Frames, International, Windows, Top @chapter Frames and X Windows @cindex frames When using the X Window System, you can create multiple windows at the X level in a single Emacs session. Each X window that belongs to Emacs displays a @dfn{frame} which can contain one or several Emacs windows. A frame initially contains a single general-purpose Emacs window which you can subdivide vertically or horizontally into smaller windows. A frame normally contains its own echo area and minibuffer, but you can make frames that don't have these---they use the echo area and minibuffer of another frame. Editing you do in one frame also affects the other frames. For instance, if you put text in the kill ring in one frame, you can yank it in another frame. If you exit Emacs through @kbd{C-x C-c} in one frame, it terminates all the frames. To delete just one frame, use @kbd{C-x 5 0}. To avoid confusion, we reserve the word ``window'' for the subdivisions that Emacs implements, and never use it to refer to a frame. Emacs compiled for MS-DOS emulates some aspects of the window system so that you can use many of the features described in this chapter. @xref{MS-DOS Input}, for more information. @cindex MS Windows Emacs compiled for MS Windows mostly supports the same features as under X. However, images, tool bars, and tooltips are not yet available on MS Windows as of Emacs version 21.1. @menu * Mouse Commands:: Moving, cutting, and pasting, with the mouse. * Secondary Selection:: Cutting without altering point and mark. * Clipboard:: Using the clipboard for selections. * Mouse References:: Using the mouse to select an item from a list. * Menu Mouse Clicks:: Mouse clicks that bring up menus. * Mode Line Mouse:: Mouse clicks on the mode line. * Creating Frames:: Creating additional Emacs frames with various contents. * Frame Commands:: Iconifying, deleting, and switching frames. * Speedbar:: How to make and use a speedbar frame. * Multiple Displays:: How one Emacs job can talk to several displays. * Special Buffer Frames:: You can make certain buffers have their own frames. * Frame Parameters:: Changing the colors and other modes of frames. * Scroll Bars:: How to enable and disable scroll bars; how to use them. * Wheeled Mice:: Using mouse wheels for scrolling. * Menu Bars:: Enabling and disabling the menu bar. * Tool Bars:: Enabling and disabling the tool bar. * Dialog Boxes:: Controlling use of dialog boxes. * Tooltips:: Showing "tooltips", AKA "ballon help" for active text. * Mouse Avoidance:: Moving the mouse pointer out of the way. * Non-Window Terminals:: Multiple frames on terminals that show only one. * XTerm Mouse:: Using the mouse in an XTerm terminal emulator. @end menu @node Mouse Commands @section Mouse Commands for Editing @cindex mouse buttons (what they do) The mouse commands for selecting and copying a region are mostly compatible with the @code{xterm} program. You can use the same mouse commands for copying between Emacs and other X client programs. @kindex DELETE @r{(and mouse selection)} If you select a region with any of these mouse commands, and then immediately afterward type the @key{DELETE} function key, it deletes the region that you selected. The @key{BACKSPACE} function key and the ASCII character @key{DEL} do not do this; if you type any other key in between the mouse command and @key{DELETE}, it does not do this. @findex mouse-set-region @findex mouse-set-point @findex mouse-yank-at-click @findex mouse-save-then-click @kindex Mouse-1 @kindex Mouse-2 @kindex Mouse-3 @table @kbd @item Mouse-1 Move point to where you click (@code{mouse-set-point}). This is normally the left button. @item Drag-Mouse-1 Set the region to the text you select by dragging, and copy it to the kill ring (@code{mouse-set-region}). You can specify both ends of the region with this single command. @vindex mouse-scroll-min-lines If you move the mouse off the top or bottom of the window while dragging, the window scrolls at a steady rate until you move the mouse back into the window. This way, you can select regions that don't fit entirely on the screen. The number of lines scrolled per step depends on how far away from the window edge the mouse has gone; the variable @code{mouse-scroll-min-lines} specifies a minimum step size. @item Mouse-2 Yank the last killed text, where you click (@code{mouse-yank-at-click}). This is normally the middle button. @item Mouse-3 This command, @code{mouse-save-then-kill}, has several functions depending on where you click and the status of the region. The most basic case is when you click @kbd{Mouse-1} in one place and then @kbd{Mouse-3} in another. This selects the text between those two positions as the region. It also copies the new region to the kill ring, so that you can copy it to someplace else. If you click @kbd{Mouse-1} in the text, scroll with the scroll bar, and then click @kbd{Mouse-3}, it remembers where point was before scrolling (where you put it with @kbd{Mouse-1}), and uses that position as the other end of the region. This is so that you can select a region that doesn't fit entirely on the screen. More generally, if you do not have a highlighted region, @kbd{Mouse-3} selects the text between point and the click position as the region. It does this by setting the mark where point was, and moving point to where you click. If you have a highlighted region, or if the region was set just before by dragging button 1, @kbd{Mouse-3} adjusts the nearer end of the region by moving it to where you click. The adjusted region's text also replaces the old region's text in the kill ring. If you originally specified the region using a double or triple @kbd{Mouse-1}, so that the region is defined to consist of entire words or lines, then adjusting the region with @kbd{Mouse-3} also proceeds by entire words or lines. If you use @kbd{Mouse-3} a second time consecutively, at the same place, that kills the region already selected. @item Double-Mouse-1 This key sets the region around the word which you click on. If you click on a character with ``symbol'' syntax (such as underscore, in C mode), it sets the region around the symbol surrounding that character. If you click on a character with open-parenthesis or close-parenthesis syntax, it sets the region around the parenthetical grouping (sexp) which that character starts or ends. If you click on a character with string-delimiter syntax (such as a singlequote or doublequote in C), it sets the region around the string constant (using heuristics to figure out whether that character is the beginning or the end of it). @item Double-Drag-Mouse-1 This key selects a region made up of the words you drag across. @item Triple-Mouse-1 This key sets the region around the line you click on. @item Triple-Drag-Mouse-1 This key selects a region made up of the lines you drag across. @end table The simplest way to kill text with the mouse is to press @kbd{Mouse-1} at one end, then press @kbd{Mouse-3} twice at the other end. @xref{Killing}. To copy the text into the kill ring without deleting it from the buffer, press @kbd{Mouse-3} just once---or just drag across the text with @kbd{Mouse-1}. Then you can copy it elsewhere by yanking it. @vindex mouse-yank-at-point To yank the killed or copied text somewhere else, move the mouse there and press @kbd{Mouse-2}. @xref{Yanking}. However, if @code{mouse-yank-at-point} is non-@code{nil}, @kbd{Mouse-2} yanks at point. Then it does not matter where you click, or even which of the frame's windows you click on. The default value is @code{nil}. This variable also affects yanking the secondary selection. @cindex cutting and X @cindex pasting and X @cindex X cutting and pasting To copy text to another X window, kill it or save it in the kill ring. Under X, this also sets the @dfn{primary selection}. Then use the ``paste'' or ``yank'' command of the program operating the other window to insert the text from the selection. To copy text from another X window, use the ``cut'' or ``copy'' command of the program operating the other window, to select the text you want. Then yank it in Emacs with @kbd{C-y} or @kbd{Mouse-2}. These cutting and pasting commands also work on MS-Windows. @cindex primary selection @cindex cut buffer @cindex selection, primary @vindex x-cut-buffer-max When Emacs puts text into the kill ring, or rotates text to the front of the kill ring, it sets the @dfn{primary selection} in the X server. This is how other X clients can access the text. Emacs also stores the text in the cut buffer, but only if the text is short enough (@code{x-cut-buffer-max} specifies the maximum number of characters); putting long strings in the cut buffer can be slow. The commands to yank the first entry in the kill ring actually check first for a primary selection in another program; after that, they check for text in the cut buffer. If neither of those sources provides text to yank, the kill ring contents are used. @node Secondary Selection @section Secondary Selection @cindex secondary selection The @dfn{secondary selection} is another way of selecting text using X. It does not use point or the mark, so you can use it to kill text without setting point or the mark. @table @kbd @findex mouse-set-secondary @kindex M-Drag-Mouse-1 @item M-Drag-Mouse-1 Set the secondary selection, with one end at the place where you press down the button, and the other end at the place where you release it (@code{mouse-set-secondary}). The highlighting appears and changes as you drag. If you move the mouse off the top or bottom of the window while dragging, the window scrolls at a steady rate until you move the mouse back into the window. This way, you can mark regions that don't fit entirely on the screen. @findex mouse-start-secondary @kindex M-Mouse-1 @item M-Mouse-1 Set one endpoint for the @dfn{secondary selection} (@code{mouse-start-secondary}). @findex mouse-secondary-save-then-kill @kindex M-Mouse-3 @item M-Mouse-3 Make a secondary selection, using the place specified with @kbd{M-Mouse-1} as the other end (@code{mouse-secondary-save-then-kill}). A second click at the same place kills the secondary selection just made. @findex mouse-yank-secondary @kindex M-Mouse-2 @item M-Mouse-2 Insert the secondary selection where you click (@code{mouse-yank-secondary}). This places point at the end of the yanked text. @end table Double or triple clicking of @kbd{M-Mouse-1} operates on words and lines, much like @kbd{Mouse-1}. If @code{mouse-yank-at-point} is non-@code{nil}, @kbd{M-Mouse-2} yanks at point. Then it does not matter precisely where you click; all that matters is which window you click on. @xref{Mouse Commands}. @node Clipboard @section Using the Clipboard @cindex X clipboard @cindex clipboard @vindex x-select-enable-clipboard @findex menu-bar-enable-clipboard @cindex OpenWindows @cindex Gnome As well as the primary and secondary selection types, X supports a @dfn{clipboard} selection type which is used by some applications, particularly under OpenWindows and Gnome. The command @kbd{M-x menu-bar-enable-clipboard} makes the @code{Cut}, @code{Paste} and @code{Copy} menu items, as well as the keys of the same names, all use the clipboard. You can customize the option @code{x-select-enable-clipboard} to make the Emacs yank functions consult the clipboard before the primary selection, and to make the kill functions to store in the clipboard as well as the primary selection. Otherwise they do not access the clipboard at all. Using the clipboard is the default on MS-Windows, unlike most systems. @node Mouse References @section Following References with the Mouse @kindex Mouse-2 @r{(selection)} Some Emacs buffers display lists of various sorts. These include lists of files, of buffers, of possible completions, of matches for a pattern, and so on. Since yanking text into these buffers is not very useful, most of them define @kbd{Mouse-2} specially, as a command to use or view the item you click on. For example, if you click @kbd{Mouse-2} on a file name in a Dired buffer, you visit that file. If you click @kbd{Mouse-2} on an error message in the @samp{*Compilation*} buffer, you go to the source code for that error message. If you click @kbd{Mouse-2} on a completion in the @samp{*Completions*} buffer, you choose that completion. You can usually tell when @kbd{Mouse-2} has this special sort of meaning because the sensitive text highlights when you move the mouse over it. @node Menu Mouse Clicks @section Mouse Clicks for Menus Mouse clicks modified with the @key{CTRL} and @key{SHIFT} keys bring up menus. @table @kbd @item C-Mouse-1 @kindex C-Mouse-1 This menu is for selecting a buffer. The MSB (``mouse select buffer'') global minor mode makes this menu smarter and more customizable. @xref{Buffer Menus}. @item C-Mouse-2 @kindex C-Mouse-2 This menu is for specifying faces and other text properties for editing formatted text. @xref{Formatted Text}. @item C-Mouse-3 @kindex C-Mouse-3 This menu is mode-specific. For most modes if Menu-bar mode is on, this menu has the same items as all the mode-specific menu-bar menus put together. Some modes may specify a different menu for this button.@footnote{Some systems use @kbd{Mouse-3} for a mode-specific menu. We took a survey of users, and found they preferred to keep @kbd{Mouse-3} for selecting and killing regions. Hence the decision to use @kbd{C-Mouse-3} for this menu.} If Menu-bar mode is off, this menu contains all the items which would be present in the menu bar---not just the mode-specific ones---so that you can access them without having to display the menu bar. @item S-Mouse-1 This menu is for specifying the frame's principal font. @end table @node Mode Line Mouse @section Mode Line Mouse Commands @cindex mode line, mouse @cindex mouse on mode line You can use mouse clicks on window mode lines to select and manipulate windows. @table @kbd @item Mouse-1 @kindex Mouse-1 @r{(mode line)} @kbd{Mouse-1} on a mode line selects the window above. By dragging @kbd{Mouse-1} on the mode line, you can move it, thus changing the height of the windows above and below. @item Mouse-2 @kindex Mouse-2 @r{(mode line)} @kbd{Mouse-2} on a mode line expands that window to fill its frame. @item Mouse-3 @kindex Mouse-3 @r{(mode line)} @kbd{Mouse-3} on a mode line deletes the window above. If the frame has only one window, it buries the current buffer instead and switches to another buffer. @item C-Mouse-2 @kindex C-mouse-2 @r{(mode line)} @kbd{C-Mouse-2} on a mode line splits the window above horizontally, above the place in the mode line where you click. @end table @kindex C-Mouse-2 @r{(scroll bar)} @kbd{C-Mouse-2} on a scroll bar splits the corresponding window vertically, unless you are using an X toolkit's implentation of scroll bars. @xref{Split Window}. The commands above apply to areas of the mode line which do not have special mouse bindings of their own. Some areas, such as the buffer name and the major mode name, have their own special mouse bindings. Emacs displays information about these bindings when you hold the mouse over such a place. @node Creating Frames @section Creating Frames @cindex creating frames @kindex C-x 5 The prefix key @kbd{C-x 5} is analogous to @kbd{C-x 4}, with parallel subcommands. The difference is that @kbd{C-x 5} commands create a new frame rather than just a new window in the selected frame (@pxref{Pop Up Window}). If an existing visible or iconified frame already displays the requested material, these commands use the existing frame, after raising or deiconifying as necessary. The various @kbd{C-x 5} commands differ in how they find or create the buffer to select: @table @kbd @item C-x 5 2 @kindex C-x 5 2 @findex make-frame-command Create a new frame (@code{make-frame-command}). @item C-x 5 b @var{bufname} @key{RET} Select buffer @var{bufname} in another frame. This runs @code{switch-to-buffer-other-frame}. @item C-x 5 f @var{filename} @key{RET} Visit file @var{filename} and select its buffer in another frame. This runs @code{find-file-other-frame}. @xref{Visiting}. @item C-x 5 d @var{directory} @key{RET} Select a Dired buffer for directory @var{directory} in another frame. This runs @code{dired-other-frame}. @xref{Dired}. @item C-x 5 m Start composing a mail message in another frame. This runs @code{mail-other-frame}. It is the other-frame variant of @kbd{C-x m}. @xref{Sending Mail}. @item C-x 5 . Find a tag in the current tag table in another frame. This runs @code{find-tag-other-frame}, the multiple-frame variant of @kbd{M-.}. @xref{Tags}. @item C-x 5 r @var{filename} @key{RET} @kindex C-x 5 r @findex find-file-read-only-other-frame Visit file @var{filename} read-only, and select its buffer in another frame. This runs @code{find-file-read-only-other-frame}. @xref{Visiting}. @end table @cindex default-frame-alist @cindex initial-frame-alist You can control the appearance of new frames you create by setting the frame parameters in @code{default-frame-alist}. You can use the variable @code{initial-frame-alist} to specify parameters that affect only the initial frame. @xref{Initial Parameters,,, elisp, The Emacs Lisp Reference Manual}, for more information. @cindex font (default) The easiest way to specify the principal font for all your Emacs frames is with an X resource (@pxref{Font X}), but you can also do it by modifying @code{default-frame-alist} to specify the @code{font} parameter, as shown here: @example (add-to-list 'default-frame-alist '(font . "10x20")) @end example @node Frame Commands @section Frame Commands The following commands let you create, delete and operate on frames: @table @kbd @item C-z @kindex C-z @r{(X windows)} @findex iconify-or-deiconify-frame Iconify the selected Emacs frame (@code{iconify-or-deiconify-frame}). The normal meaning of @kbd{C-z}, to suspend Emacs, is not useful under a window system, so it has a different binding in that case. If you type this command on an Emacs frame's icon, it deiconifies the frame. @item C-x 5 0 @kindex C-x 5 0 @findex delete-frame Delete the selected frame (@code{delete-frame}). This is not allowed if there is only one frame. @item C-x 5 o @kindex C-x 5 o @findex other-frame Select another frame, raise it, and warp the mouse to it so that it stays selected. If you repeat this command, it cycles through all the frames on your terminal. @item C-x 5 1 @kindex C-x 5 1 @findex delete-other-frames Delete all frames except the selected one. @end table @node Speedbar @section Making and Using a Speedbar Frame @cindex speedbar An Emacs frame can have a @dfn{speedbar}, which is a vertical window that serves as a scrollable menu of files you could visit and tags within those files. To create a speedbar, type @kbd{M-x speedbar}; this creates a speedbar window for the selected frame. From then on, you can click on a file name in the speedbar to visit that file in the corresponding Emacs frame, or click on a tag name to jump to that tag in the Emacs frame. Initially the speedbar lists the immediate contents of the current directory, one file per line. Each line also has a box, @samp{[+]} or @samp{<+>}, that you can click on with @kbd{Mouse-2} to ``open up'' the contents of that item. If the line names a directory, opening it adds the contents of that directory to the speedbar display, underneath the directory's own line. If the line lists an ordinary file, opening it up adds a list of the tags in that file to the speedbar display. When a file is opened up, the @samp{[+]} changes to @samp{[-]}; you can click on that box to ``close up'' that file (hide its contents). Some major modes, including Rmail mode, Info, and GUD, have specialized ways of putting useful items into the speedbar for you to select. For example, in Rmail mode, the speedbar shows a list of Rmail files, and lets you move the current message to another Rmail file by clicking on its @samp{} box. A speedbar belongs to one Emacs frame, and always operates on that frame. If you use multiple frames, you can make a speedbar for some or all of the frames; type @kbd{M-x speedbar} in any given frame to make a speedbar for it. @node Multiple Displays @section Multiple Displays @cindex multiple displays A single Emacs can talk to more than one X display. Initially, Emacs uses just one display---the one specified with the @env{DISPLAY} environment variable or with the @samp{--display} option (@pxref{Initial Options}). To connect to another display, use the command @code{make-frame-on-display}: @findex make-frame-on-display @table @kbd @item M-x make-frame-on-display @key{RET} @var{display} @key{RET} Create a new frame on display @var{display}. @end table A single X server can handle more than one screen. When you open frames on two screens belonging to one server, Emacs knows they share a single keyboard, and it treats all the commands arriving from these screens as a single stream of input. When you open frames on different X servers, Emacs makes a separate input stream for each server. This way, two users can type simultaneously on the two displays, and Emacs will not garble their input. Each server also has its own selected frame. The commands you enter with a particular X server apply to that server's selected frame. Despite these features, people using the same Emacs job from different displays can still interfere with each other if they are not careful. For example, if any one types @kbd{C-x C-c}, that exits the Emacs job for all of them! @node Special Buffer Frames @section Special Buffer Frames @vindex special-display-buffer-names You can make certain chosen buffers, for which Emacs normally creates a second window when you have just one window, appear in special frames of their own. To do this, set the variable @code{special-display-buffer-names} to a list of buffer names; any buffer whose name is in that list automatically gets a special frame, when an Emacs command wants to display it ``in another window.'' For example, if you set the variable this way, @example (setq special-display-buffer-names '("*Completions*" "*grep*" "*tex-shell*")) @end example @noindent then completion lists, @code{grep} output and the @TeX{} mode shell buffer get individual frames of their own. These frames, and the windows in them, are never automatically split or reused for any other buffers. They continue to show the buffers they were created for, unless you alter them by hand. Killing the special buffer deletes its frame automatically. @vindex special-display-regexps More generally, you can set @code{special-display-regexps} to a list of regular expressions; then a buffer gets its own frame if its name matches any of those regular expressions. (Once again, this applies only to buffers that normally get displayed for you in a separate window.) @vindex special-display-frame-alist The variable @code{special-display-frame-alist} specifies the frame parameters for these frames. It has a default value, so you don't need to set it. For those who know Lisp, an element of @code{special-display-buffer-names} or @code{special-display-regexps} can also be a list. Then the first element is the buffer name or regular expression; the rest of the list specifies how to create the frame. It can be an association list specifying frame parameter values; these values take precedence over parameter values specified in @code{special-display-frame-alist}. Alternatively, it can have this form: @example (@var{function} @var{args}...) @end example @noindent where @var{function} is a symbol. Then the frame is constructed by calling @var{function}; its first argument is the buffer, and its remaining arguments are @var{args}. An analogous feature lets you specify buffers which should be displayed in the selected window. @xref{Force Same Window}. The same-window feature takes precedence over the special-frame feature; therefore, if you add a buffer name to @code{special-display-buffer-names} and it has no effect, check to see whether that feature is also in use for the same buffer name. @node Frame Parameters @section Setting Frame Parameters @cindex colors @cindex Auto-Raise mode @cindex Auto-Lower mode This section describes commands for altering the display style and window management behavior of the selected frame. @findex set-foreground-color @findex set-background-color @findex set-cursor-color @findex set-mouse-color @findex set-border-color @findex auto-raise-mode @findex auto-lower-mode @table @kbd @item M-x set-foreground-color @key{RET} @var{color} @key{RET} Specify color @var{color} for the foreground of the selected frame. (This also changes the foreground color of the default face.) @item M-x set-background-color @key{RET} @var{color} @key{RET} Specify color @var{color} for the background of the selected frame. (This also changes the background color of the default face.) @item M-x set-cursor-color @key{RET} @var{color} @key{RET} Specify color @var{color} for the cursor of the selected frame. @item M-x set-mouse-color @key{RET} @var{color} @key{RET} Specify color @var{color} for the mouse cursor when it is over the selected frame. @item M-x set-border-color @key{RET} @var{color} @key{RET} Specify color @var{color} for the border of the selected frame. @item M-x list-colors-display Display the defined color names and show what the colors look like. This command is somewhat slow. @item M-x auto-raise-mode Toggle whether or not the selected frame should auto-raise. Auto-raise means that every time you move the mouse onto the frame, it raises the frame. Note that this auto-raise feature is implemented by Emacs itself. Some window managers also implement auto-raise. If you enable auto-raise for Emacs frames in your X window manager, it should work, but it is beyond Emacs's control and therefore @code{auto-raise-mode} has no effect on it. @item M-x auto-lower-mode Toggle whether or not the selected frame should auto-lower. Auto-lower means that every time you move the mouse off the frame, the frame moves to the bottom of the stack of X windows. The command @code{auto-lower-mode} has no effect on auto-lower implemented by the X window manager. To control that, you must use the appropriate window manager features. @findex set-frame-font @item M-x set-frame-font @key{RET} @var{font} @key{RET} @cindex font (principal) Specify font @var{font} as the principal font for the selected frame. The principal font controls several face attributes of the @code{default} face (@pxref{Faces}). For example, if the principal font has a height of 12 pt, all text will be drawn in 12 pt fonts, unless you use another face that specifies a different height. @xref{Font X}, for ways to list the available fonts on your system. @kindex S-Mouse-1 You can also set a frame's principal font through a pop-up menu. Press @kbd{S-Mouse-1} to activate this menu. @end table In Emacs versions that use an X toolkit, the color-setting and font-setting functions don't affect menus and the menu bar, since they are displayed by their own widget classes. To change the appearance of the menus and menu bar, you must use X resources (@pxref{Resources X}). @xref{Colors X}, regarding colors. @xref{Font X}, regarding choice of font. For information on frame parameters and customization, see @ref{Frame Parameters,,, elisp, The Emacs Lisp Reference Manual}. @node Scroll Bars @section Scroll Bars @cindex Scroll Bar mode @cindex mode, Scroll Bar When using X, Emacs normally makes a @dfn{scroll bar} at the left of each Emacs window.@footnote{Placing it at the left is usually more useful with overlapping frames with text starting at the left margin.} The scroll bar runs the height of the window, and shows a moving rectangular inner box which represents the portion of the buffer currently displayed. The entire height of the scroll bar represents the entire length of the buffer. You can use @kbd{Mouse-2} (normally, the middle button) in the scroll bar to move or drag the inner box up and down. If you move it to the top of the scroll bar, you see the top of the buffer. If you move it to the bottom of the scroll bar, you see the bottom of the buffer. The left and right buttons in the scroll bar scroll by controlled increments. @kbd{Mouse-1} (normally, the left button) moves the line at the level where you click up to the top of the window. @kbd{Mouse-3} (normally, the right button) moves the line at the top of the window down to the level where you click. By clicking repeatedly in the same place, you can scroll by the same distance over and over. If you are using Emacs's own implementation of scroll bars, as opposed to scroll bars from an X toolkit, you can also click @kbd{C-Mouse-2} in the scroll bar to split a window vertically. The split occurs on the line where you click. @findex scroll-bar-mode @vindex scroll-bar-mode You can enable or disable Scroll Bar mode with the command @kbd{M-x scroll-bar-mode}. With no argument, it toggles the use of scroll bars. With an argument, it turns use of scroll bars on if and only if the argument is positive. This command applies to all frames, including frames yet to be created. Customize the option @code{scroll-bar-mode} to control the use of scroll bars at startup. You can use it to specify that they are placed at the right of windows if you prefer that. You can use the X resource @samp{verticalScrollBars} to control the initial setting of Scroll Bar mode similarly. @xref{Resources X}. @findex toggle-scroll-bar To enable or disable scroll bars for just the selected frame, use the @kbd{M-x toggle-scroll-bar} command. @node Wheeled Mice @section Scrolling With ``Wheeled'' Mice @cindex mouse wheel @cindex wheel, mouse @findex mouse-wheel-mode @cindex Mouse Wheel minor mode @cindex mode, Mouse Wheel Some mice have a ``wheel'' instead of a third button. You can usually click the wheel to act as either @kbd{Mouse-2} or @kbd{Mouse-3}, depending on the setup. You can also use the wheel to scroll windows instead of using the scroll bar or keyboard commands. To do so, turn on Mouse Wheel global minor mode with the command @kbd{M-x mouse-wheel-mode} or by customizing the option @code{mouse-wheel-mode}. Support for the wheel depends on the system generating appropriate events for Emacs. @vindex mouse-wheel-follow-mouse @vindex mouse-wheel-scroll-amount The variables @code{mouse-wheel-follow-mouse} and @code{mouse-wheel-scroll-amount} determine where and by how much buffers are scrolled. @node Menu Bars @section Menu Bars @cindex Menu Bar mode @cindex mode, Menu Bar You can turn display of menu bars on or off with @kbd{M-x menu-bar-mode} or by customizing the option @code{menu-bar-mode}. With no argument, this command toggles Menu Bar mode, a minor mode. With an argument, the command turns Menu Bar mode on if the argument is positive, off if the argument is not positive. You can use the X resource @samp{menuBarLines} to control the initial setting of Menu Bar mode. @xref{Resources X}. @kindex C-Mouse-3 @r{(when menu bar is disabled)} Expert users often turn off the menu bar, especially on text-only terminals, where this makes one additional line available for text. If the menu bar is off, you can still pop up a menu of its contents with @kbd{C-Mouse-3} on a display which supports popup menus. @xref{Menu Mouse Clicks}. @xref{Menu Bar}, for information on how to invoke commands with the menu bar. @node Tool Bars @section Tool Bars @cindex Tool Bar mode @cindex mode, Tool Bar @cindex icons, tool bar The @dfn{tool bar} is a line (or multiple lines) of icons at the top of the Emacs window. You can click on these icons with the mouse to do various jobs. The global tool bar contains general commands. Some major modes define their own tool bars to replace it. A few ``special'' modes that are not designed for ordinary editing remove some items from the global tool bar. Tool bars work only on a graphical display. The tool bar uses colored XPM icons if Emacs was built with XPM support. Otherwise, the tool bar uses monochrome icons (PBM or XBM format). You can turn display of tool bars on or off with @kbd{M-x tool-bar-mode}. @node Dialog Boxes @section Using Dialog Boxes @cindex dialog boxes @vindex use-dialog-box A dialog box is a special kind of menu for asking you a yes-or-no question or some other special question. Many Emacs commands use a dialog box to ask a yes-or-no question, if you used the mouse to invoke the command to begin with. You can customize the option @code{use-dialog-box} to suppress the use of dialog boxes. This also controls whether to use file selection windows (but those are not supported on all platforms). @node Tooltips @section Tooltips (or ``Balloon Help'') @cindex balloon help Tooltips are small X windows displaying a help string at the current mouse position, typically over text---including the mode line---which can be activated with the mouse or other keys. (This facility is sometimes known as @dfn{balloon help}.) Help text may be available for menu items too. @findex tooltip-mode To use tooltips, enable Tooltip mode with the command @kbd{M-x tooltip-mode}. The customization group @code{tooltip} controls various aspects of how tooltips work. When Tooltip mode is disabled, the help text is displayed in the echo area instead. As of Emacs 21.1, tooltips are not supported on MS-Windows. @node Mouse Avoidance @section Mouse Avoidance @cindex avoiding mouse in the way of your typing @cindex mouse avoidance @vindex mouse-avoidance-mode Mouse Avoidance mode keeps the window system mouse pointer away from point, to avoid obscuring text. Whenever it moves the mouse, it also raises the frame. To use Mouse Avoidance mode, customize the option @code{mouse-avoidance-mode}. You can set this to various values to move the mouse in several ways: @table @code @item banish Move the mouse to the upper-right corner on any keypress; @item exile Move the mouse to the corner only if the cursor gets too close, and allow it to return once the cursor is out of the way; @item jump If the cursor gets too close to the mouse, displace the mouse a random distance & direction; @item animate As @code{jump}, but shows steps along the way for illusion of motion; @item cat-and-mouse The same as @code{animate}; @item proteus As @code{animate}, but changes the shape of the mouse pointer too. @end table @findex mouse-avoidance-mode You can also use the command @kbd{M-x mouse-avoidance-mode} to enable the mode. @node Non-Window Terminals @section Non-Window Terminals @cindex non-window terminals @cindex single-frame terminals If your terminal does not have a window system that Emacs supports, then it can display only one Emacs frame at a time. However, you can still create multiple Emacs frames, and switch between them. Switching frames on these terminals is much like switching between different window configurations. Use @kbd{C-x 5 2} to create a new frame and switch to it; use @kbd{C-x 5 o} to cycle through the existing frames; use @kbd{C-x 5 0} to delete the current frame. Each frame has a number to distinguish it. If your terminal can display only one frame at a time, the selected frame's number @var{n} appears near the beginning of the mode line, in the form @samp{F@var{n}}. @findex set-frame-name @findex select-frame-by-name @samp{F@var{n}} is actually the frame's name. You can also specify a different name if you wish, and you can select a frame by its name. Use the command @kbd{M-x set-frame-name @key{RET} @var{name} @key{RET}} to specify a new name for the selected frame, and use @kbd{M-x select-frame-by-name @key{RET} @var{name} @key{RET}} to select a frame according to its name. The name you specify appears in the mode line when the frame is selected. @node XTerm Mouse @section Using a Mouse in Terminal Emulators @cindex xterm, mouse support @cindex terminal emulators, mouse support Some terminal emulators under X support mouse clicks in the terminal window. In a terminal emulator which is compatible with @code{xterm}, you can use @kbd{M-x xterm-mouse-mode} to enable simple use of the mouse---only single clicks are supported. The normal @code{xterm} mouse functionality is still available by holding down the @kbd{SHIFT} key when you press the mouse button. The Linux console supports this mode if it has support for the mouse enabled, e.g.@: using the @command{gpm} daemon.