@c This is part of the Emacs manual. @c Copyright (C) 1985-1987, 1993-1995, 1997, 1999-2017 Free Software @c Foundation, Inc. @c See file emacs.texi for copying conditions. @node Frames @chapter Frames and Graphical Displays @cindex frames When Emacs is started on a graphical display, e.g., on the X Window System, it occupies a graphical system-level display region. In this manual, we call this a @dfn{frame}, reserving the word ``window'' for the part of the frame used for displaying a buffer. A frame initially contains one window, but it can be subdivided into multiple windows (@pxref{Windows}). A frame normally also contains a menu bar, tool bar, and echo area. You can also create additional frames (@pxref{Creating Frames}). All frames created in the same Emacs session have access to the same underlying buffers and other data. For instance, if a buffer is being shown in more than one frame, any changes made to it in one frame show up immediately in the other frames too. Typing @kbd{C-x C-c} closes all the frames on the current display, and ends the Emacs session if it has no frames open on any other displays (@pxref{Exiting}). To close just the selected frame, type @kbd{C-x 5 0} (that is zero, not @kbd{o}). This chapter describes Emacs features specific to graphical displays (particularly mouse commands), and features for managing multiple frames. On text terminals, many of these features are unavailable. However, it is still possible to create multiple frames on text terminals; such frames are displayed one at a time, filling the entire terminal screen (@pxref{Non-Window Terminals}). It is also possible to use the mouse on some text terminals (@pxref{Text-Only Mouse}, for doing so on GNU and Unix systems; and @iftex @pxref{MS-DOS Mouse,,,emacs-xtra,Specialized Emacs Features}, @end iftex @ifnottex @pxref{MS-DOS Mouse}, @end ifnottex for doing so on MS-DOS). Menus are supported on all text terminals. @menu * Mouse Commands:: Moving, cutting, and pasting, with the mouse. * Word and Line Mouse:: Mouse commands for selecting whole words or lines. * 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. * Fonts:: Changing the frame font. * Speedbar:: How to make and use a speedbar frame. * Multiple Displays:: How one Emacs instance can talk to several displays. * Frame Parameters:: Changing the colors and other modes of frames. * Scroll Bars:: How to enable and disable scroll bars; how to use them. * Window Dividers:: Window separators that can be dragged with the mouse. * Drag and Drop:: Using drag and drop to open files and insert text. * Menu Bars:: Enabling and disabling the menu bar. * Tool Bars:: Enabling and disabling the tool bar. * Dialog Boxes:: Controlling use of dialog boxes. * Tooltips:: Displaying information at the current mouse position. * Mouse Avoidance:: Preventing the mouse pointer from obscuring text. * Non-Window Terminals:: Multiple frames on terminals that show only one. * Text-Only Mouse:: Using the mouse in text terminals. @end menu @node Mouse Commands @section Mouse Commands for Editing @cindex mouse buttons (what they do) @cindex mouse, selecting text using @kindex mouse-1 @kindex mouse-2 @kindex mouse-3 @table @kbd @item mouse-1 Move point to where you click (@code{mouse-set-point}). @item Drag-mouse-1 Activate the region around the text selected by dragging, and put the text in the primary selection (@code{mouse-set-region}). @item mouse-2 Move point to where you click, and insert the contents of the primary selection there (@code{mouse-yank-primary}). @item mouse-3 If the region is active, move the nearer end of the region to the click position; otherwise, set mark at the current value of point and point at the click position. Save the resulting region in the kill ring; on a second click, kill it (@code{mouse-save-then-kill}). @end table @findex mouse-set-point The most basic mouse command is @code{mouse-set-point}, which is invoked by clicking with the left mouse button, @kbd{mouse-1}, in the text area of a window. This moves point to the position where you clicked. If that window was not the selected window, it becomes the selected window. You can also activate a region by double-clicking mouse-1 (@pxref{Word and Line Mouse}). @vindex x-mouse-click-focus-ignore-position Normally, if the frame you clicked in was not the selected frame, it is made the selected frame, in addition to selecting the window and setting the cursor. On the X Window System, you can change this by setting the variable @code{x-mouse-click-focus-ignore-position} to @code{t}. In that case, the initial click on an unselected frame just selects the frame, without doing anything else; clicking again selects the window and sets the cursor position. @cindex mouse, dragging @findex mouse-set-region Holding down @kbd{mouse-1} and dragging the mouse over a stretch of text activates the region around that text (@code{mouse-set-region}), placing the mark where you started holding down the mouse button, and point where you release it (@pxref{Mark}). In addition, the text in the region becomes the primary selection (@pxref{Primary Selection}). @vindex mouse-drag-copy-region If you change the variable @code{mouse-drag-copy-region} to a non-@code{nil} value, dragging the mouse over a stretch of text also adds the text to the kill ring. The default is @code{nil}. @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. @findex mouse-yank-primary @findex mouse-yank-at-click Clicking with the middle mouse button, @kbd{mouse-2}, moves point to the position where you clicked and inserts the contents of the primary selection (@code{mouse-yank-primary}). @xref{Primary Selection}. This behavior is consistent with other X applications. Alternatively, you can rebind @kbd{mouse-2} to @code{mouse-yank-at-click}, which performs a yank at the position you click. @vindex mouse-yank-at-point If you change the variable @code{mouse-yank-at-point} to a non-@code{nil} value, @kbd{mouse-2} does not move point; it inserts the text at point, regardless of where you clicked or even which of the frame's windows you clicked on. This variable affects both @code{mouse-yank-primary} and @code{mouse-yank-at-click}. @findex mouse-save-then-kill Clicking with the right mouse button, @kbd{mouse-3}, runs the command @code{mouse-save-then-kill}. This performs several actions depending on where you click and the status of the region: @itemize @bullet @item If no region is active, clicking @kbd{mouse-3} activates the region, placing the mark where point was and point at the clicked position. @item If a region is active, clicking @kbd{mouse-3} adjusts the nearer end of the region by moving it to the clicked position. The adjusted region's text is copied to the kill ring; if the text in the original region was already on the kill ring, it replaces it there. @item 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 (@pxref{Word and Line Mouse}), then adjusting the region with @kbd{mouse-3} also proceeds by entire words or lines. @item If you use @kbd{mouse-3} a second time consecutively, at the same place, that kills the region already selected. Thus, the simplest way to kill text with the mouse is to click @kbd{mouse-1} at one end, then click @kbd{mouse-3} twice at the other end. 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. @end itemize The @code{mouse-save-then-kill} command also obeys the variable @code{mouse-drag-copy-region} (described above). If the value is non-@code{nil}, then whenever the command sets or adjusts the active region, the text in the region is also added to the kill ring. If the latest kill ring entry had been added the same way, that entry is replaced rather than making a new entry. Whenever you set the region using any of the mouse commands described above, the mark will be deactivated by any subsequent unshifted cursor motion command, in addition to the usual ways of deactivating the mark. @xref{Shift Selection}. @cindex mouse wheel @findex mouse-wheel-mode @cindex Mouse Wheel minor mode @cindex mode, Mouse Wheel @vindex mouse-wheel-follow-mouse @vindex mouse-wheel-scroll-amount @vindex mouse-wheel-progressive-speed Some mice have a ``wheel'' which can be used for scrolling. Emacs supports scrolling windows with the mouse wheel, by default, on most graphical displays. To toggle this feature, use @kbd{M-x mouse-wheel-mode}. The variables @code{mouse-wheel-follow-mouse} and @code{mouse-wheel-scroll-amount} determine where and by how much buffers are scrolled. The variable @code{mouse-wheel-progressive-speed} determines whether the scroll speed is linked to how fast you move the wheel. @vindex mwheel-tilt-scroll-p @vindex mwheel-flip-direction Emacs can also support horizontal scrolling if your mouse's wheel can be tilted. This feature is off by default; the variable @code{mwheel-tilt-scroll-p} turns it on. If you'd like to reverse the direction of horizontal scrolling, customize the variable @code{mwheel-flip-direction} to a non-@code{nil} value. @node Word and Line Mouse @section Mouse Commands for Words and Lines These variants of @kbd{mouse-1} select entire words or lines at a time. Emacs activates the region around the selected text, which is also copied to the kill ring. @table @kbd @item Double-mouse-1 Select the text around the word or character which you click on. Double-clicking on a character with symbol syntax (such as underscore, in C mode) selects the symbol surrounding that character. Double-clicking on a character with open- or close-parenthesis syntax selects the parenthetical grouping which that character starts or ends. Double-clicking on a character with string-delimiter syntax (such as a single-quote or double-quote in C) selects the string constant (Emacs uses heuristics to figure out whether that character is the beginning or the end of it). Double-clicking on the beginning of a parenthetical grouping or beginning string-delimiter moves point to the end of the region, scrolling the buffer display forward if necessary to show the new location of point. Double-clicking on the end of a parenthetical grouping or end string-delimiter keeps point at the end of the region by default, so the beginning of the region will not be visible if it is above the top of the window; setting the user option @code{mouse-select-region-move-to-beginning} to non-nil changes this to move point to the beginning of the region, scrolling the display backward if necessary. @item Double-Drag-mouse-1 Select the text you drag across, in the form of whole words. @item Triple-mouse-1 Select the line you click on. @item Triple-Drag-mouse-1 Select the text you drag across, in the form of whole lines. @end table @node Mouse References @section Following References with the Mouse @kindex mouse-1 @r{(on buttons)} @kindex mouse-2 @r{(on buttons)} @cindex hyperlinks @cindex links @cindex text buttons @cindex buttons @vindex mouse-highlight Some Emacs buffers include @dfn{buttons}, or @dfn{hyperlinks}: pieces of text that perform some action (e.g., following a reference) when activated (e.g., by clicking on them). Usually, a button's text is visually highlighted: it is underlined, or a box is drawn around it. If you move the mouse over a button, the shape of the mouse cursor changes and the button lights up. If you change the variable @code{mouse-highlight} to @code{nil}, Emacs disables this highlighting. You can activate a button by moving point to it and typing @key{RET}, or by clicking either @kbd{mouse-1} or @kbd{mouse-2} on the button. For example, in a Dired buffer, each file name is a button; activating it causes Emacs to visit that file (@pxref{Dired}). In a @file{*Compilation*} buffer, each error message is a button, and activating it visits the source code for that error (@pxref{Compilation}). Although clicking @kbd{mouse-1} on a button usually activates the button, if you hold the mouse button down for a period of time before releasing it (specifically, for more than 450 milliseconds), then Emacs moves point where you clicked, without activating the button. In this way, you can use the mouse to move point over a button without activating it. Dragging the mouse over or onto a button has its usual behavior of setting the region, and does not activate the button. You can change how @kbd{mouse-1} applies to buttons by customizing the variable @code{mouse-1-click-follows-link}. If the value is a positive integer, that determines how long you need to hold the mouse button down for, in milliseconds, to cancel button activation; the default is 450, as described in the previous paragraph. If the value is @code{nil}, @kbd{mouse-1} just sets point where you clicked, and does not activate buttons. If the value is @code{double}, double clicks activate buttons but single clicks just set point. @vindex mouse-1-click-in-non-selected-windows Normally, @kbd{mouse-1} on a button activates the button even if it is in a non-selected window. If you change the variable @code{mouse-1-click-in-non-selected-windows} to @code{nil}, @kbd{mouse-1} on a button in an unselected window moves point to the clicked position and selects that window, without activating the button. @node Menu Mouse Clicks @section Mouse Clicks for Menus Several mouse clicks with the @key{CTRL} and @key{SHIFT} modifiers 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 contains entries for examining faces and other text properties, and well as for setting them (the latter is mainly useful when editing enriched text; @pxref{Enriched 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. 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 changing the default face within the window's buffer. @xref{Text Scale}. @end table Some graphical applications use @kbd{mouse-3} for a mode-specific menu. If you prefer @kbd{mouse-3} in Emacs to bring up such a menu instead of running the @code{mouse-save-then-kill} command, rebind @kbd{mouse-3} by adding the following line to your init file (@pxref{Init Rebinding}): @c FIXME: `mouse-popup-menubar-stuff' is obsolete since 23.1. @smallexample (global-set-key [mouse-3] 'mouse-popup-menubar-stuff) @end smallexample @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. Some areas of the mode line, such as the buffer name, and major and minor mode names, have their own special mouse bindings. These areas are highlighted when you hold the mouse over them, and information about the special bindings will be displayed (@pxref{Tooltips}). This section's commands do not apply in those areas. @table @kbd @item mouse-1 @kindex mouse-1 @r{(mode line)} @kbd{mouse-1} on a mode line selects the window it belongs to. By dragging @kbd{mouse-1} on the mode line, you can move it, thus changing the height of the windows above and below. Changing heights with the mouse in this way never deletes windows, it just refuses to make any window smaller than the minimum height. @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 it belongs to. If the frame has only one window, it does nothing. @item C-mouse-2 @kindex C-mouse-2 @r{(mode line)} @kbd{C-mouse-2} on a mode line splits that window, producing two side-by-side windows with the boundary running through the click position (@pxref{Split Window}). @end table @kindex mouse-1 @r{(scroll bar)} Furthermore, by clicking and dragging @kbd{mouse-1} on the divider between two side-by-side mode lines, you can move the vertical boundary to the left or right. Note that resizing windows is affected by the value of @code{window-resize-pixelwise}, see @ref{Split Window}. @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}. Whereas each @kbd{C-x 4} command pops up a buffer in a different window in the selected frame (@pxref{Pop Up Window}), the @kbd{C-x 5} commands use a different frame. If an existing visible or iconified (a.k.a.@: ``minimized'') frame already displays the requested buffer, that frame is raised and deiconified (``un-minimized''); otherwise, a new frame is created on the current display terminal. 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{compose-mail-other-frame}. It is the other-frame variant of @kbd{C-x m}. @xref{Sending Mail}. @item C-x 5 . Find the definition of an identifier in another frame. This runs @code{xref-find-definitions-other-frame}, the multiple-frame variant of @kbd{M-.}. @xref{Xref}. @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 You can control the appearance and behavior of the newly-created frames by specifying @dfn{frame parameters}. @xref{Frame Parameters}. @node Frame Commands @section Frame Commands The following commands are used to delete and operate on frames: @table @kbd @item C-x 5 0 @kindex C-x 5 0 @findex delete-frame Delete the selected frame (@code{delete-frame}). This signals an error if there is only one frame. @item C-z @kindex C-z @r{(X windows)} @findex suspend-frame Minimize (or iconify) the selected Emacs frame (@code{suspend-frame}). @xref{Exiting}. @item C-x 5 o @kindex C-x 5 o @findex other-frame Select another frame, and raise it. 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 on the current terminal, except the selected one. @item M- @kindex M- @findex toggle-frame-maximized Toggle the maximization state of the current frame. When a frame is maximized, it fills the screen. @item @kindex @findex toggle-frame-fullscreen Toggle full-screen mode for the current frame. (The difference between full-screen and maximized is normally that the former hides window manager decorations, giving slightly more screen space to Emacs itself.) @end table @vindex frame-resize-pixelwise Note that with some window managers you may have to customize the variable @code{frame-resize-pixelwise} to a non-@code{nil} value in order to make a frame truly maximized or full-screen. This variable, when set to a non-@code{nil} value, in general allows resizing frames at pixel resolution, rather than in integral multiples of lines and columns. The @kbd{C-x 5 0} (@code{delete-frame}) command deletes the selected frame. However, it will refuse to delete the last frame in an Emacs session, to prevent you from losing the ability to interact with the Emacs session. Note that when Emacs is run as a daemon (@pxref{Emacs Server}), there is always a virtual frame that remains after all the ordinary, interactive frames are deleted. In this case, @kbd{C-x 5 0} can delete the last interactive frame; you can use @command{emacsclient} to reconnect to the Emacs session. The @kbd{C-x 5 1} (@code{delete-other-frames}) command deletes all other frames on the current terminal (this terminal refers to either a graphical display, or a text terminal; @pxref{Non-Window Terminals}). If the Emacs session has frames open on other graphical displays or text terminals, those are not deleted. @vindex focus-follows-mouse The @kbd{C-x 5 o} (@code{other-frame}) command selects the next frame on the current terminal. If you are using Emacs on the X Window System with a window manager that selects (or @dfn{gives focus to}) whatever frame the mouse cursor is over, you have to change the variable @code{focus-follows-mouse} to @code{t} in order for this command to work properly. Then invoking @kbd{C-x 5 o} will also warp the mouse cursor to the chosen frame. @node Fonts @section Fonts @cindex fonts By default, Emacs displays text on graphical displays using a 10-point monospace font. There are several different ways to specify a different font: @itemize @item Click on @samp{Set Default Font} in the @samp{Options} menu. This makes the selected font the default on all existing graphical frames. To save this for future sessions, click on @samp{Save Options} in the @samp{Options} menu. @item Add a line to your init file, modifying the variable @code{default-frame-alist} to specify the @code{font} parameter (@pxref{Frame Parameters}), like this: @example (add-to-list 'default-frame-alist '(font . "DejaVu Sans Mono-10")) @end example @noindent This makes the font the default on all graphical frames created after restarting Emacs with that init file. @cindex X defaults file @cindex X resources file @item Add an @samp{emacs.font} X resource setting to your X resource file, like this: @example emacs.font: DejaVu Sans Mono-12 @end example @noindent You must restart X, or use the @command{xrdb} command, for the X resources file to take effect. @xref{Resources}. Do not quote font names in X resource files. @item If you are running Emacs on the GNOME desktop, you can tell Emacs to use the default system font by setting the variable @code{font-use-system-font} to @code{t} (the default is @code{nil}). For this to work, Emacs must have been compiled with support for Gsettings (or the older Gconf). @item Use the command line option @samp{-fn} (or @samp{--font}). @xref{Font X}. @end itemize To check what font you're currently using, the @kbd{C-u C-x =} command can be helpful. It describes the character at point, and names the font that it's rendered in. @cindex fontconfig On X, there are four different ways to express a font name. The first is to use a @dfn{Fontconfig pattern}. Fontconfig patterns have the following form: @example @var{fontname}[-@var{fontsize}][:@var{name1}=@var{values1}][:@var{name2}=@var{values2}]... @end example @noindent Within this format, any of the elements in brackets may be omitted. Here, @var{fontname} is the @dfn{family name} of the font, such as @samp{Monospace} or @samp{DejaVu Sans Mono}; @var{fontsize} is the @dfn{point size} of the font (one @dfn{printer's point} is about 1/72 of an inch); and the @samp{@var{name}=@var{values}} entries specify settings such as the slant and weight of the font. Each @var{values} may be a single value, or a list of values separated by commas. In addition, some property values are valid with only one kind of property name, in which case the @samp{@var{name}=} part may be omitted. Here is a list of common font properties: @table @samp @item slant One of @samp{italic}, @samp{oblique}, or @samp{roman}. @item weight One of @samp{light}, @samp{medium}, @samp{demibold}, @samp{bold} or @samp{black}. @item style Some fonts define special styles which are a combination of slant and weight. For instance, @samp{Dejavu Sans} defines the @samp{book} style, which overrides the slant and weight properties. @item width One of @samp{condensed}, @samp{normal}, or @samp{expanded}. @item spacing One of @samp{monospace}, @samp{proportional}, @samp{dual-width}, or @samp{charcell}. @end table @noindent Here are some examples of Fontconfig patterns: @example Monospace Monospace-12 Monospace-12:bold DejaVu Sans Mono:bold:italic Monospace-12:weight=bold:slant=italic @end example For a more detailed description of Fontconfig patterns, see the Fontconfig manual, which is distributed with Fontconfig and available online at @url{http://fontconfig.org/fontconfig-user.html}. @cindex GTK font pattern The second way to specify a font is to use a @dfn{GTK font pattern}. These have the syntax @example @var{fontname} [@var{properties}] [@var{fontsize}] @end example @noindent where @var{fontname} is the family name, @var{properties} is a list of property values separated by spaces, and @var{fontsize} is the point size. The properties that you may specify for GTK font patterns are as follows: @itemize @item Slant properties: @samp{Italic} or @samp{Oblique}. If omitted, the default (roman) slant is implied. @item Weight properties: @samp{Bold}, @samp{Book}, @samp{Light}, @samp{Medium}, @samp{Semi-bold}, or @samp{Ultra-light}. If omitted, @samp{Medium} weight is implied. @item Width properties: @samp{Semi-Condensed} or @samp{Condensed}. If omitted, a default width is used. @end itemize @noindent Here are some examples of GTK font patterns: @example Monospace 12 Monospace Bold Italic 12 @end example @cindex XLFD @cindex X Logical Font Description The third way to specify a font is to use an @dfn{XLFD} (@dfn{X Logical Font Description}). This is the traditional method for specifying fonts under X@. Each XLFD consists of fourteen words or numbers, separated by dashes, like this: @example -misc-fixed-medium-r-semicondensed--13-*-*-*-c-60-iso8859-1 @end example @noindent A wildcard character (@samp{*}) in an XLFD matches any sequence of characters (including none), and @samp{?} matches any single character. However, matching is implementation-dependent, and can be inaccurate when wildcards match dashes in a long name. For reliable results, supply all 14 dashes and use wildcards only within a field. Case is insignificant in an XLFD@. The syntax for an XLFD is as follows: @example -@var{maker}-@var{family}-@var{weight}-@var{slant}-@var{widthtype}-@var{style}@dots{} @dots{}-@var{pixels}-@var{height}-@var{horiz}-@var{vert}-@var{spacing}-@var{width}-@var{registry}-@var{encoding} @end example @noindent The entries have the following meanings: @table @var @item maker The name of the font manufacturer. @item family The name of the font family (e.g., @samp{courier}). @item weight The font weight---normally either @samp{bold}, @samp{medium} or @samp{light}. Some font names support other values. @item slant The font slant---normally @samp{r} (roman), @samp{i} (italic), @samp{o} (oblique), @samp{ri} (reverse italic), or @samp{ot} (other). Some font names support other values. @item widthtype The font width---normally @samp{normal}, @samp{condensed}, @samp{semicondensed}, or @samp{extended}. Some font names support other values. @item style An optional additional style name. Usually it is empty---most XLFDs have two hyphens in a row at this point. The style name can also specify a two-letter ISO-639 language name, like @samp{ja} or @samp{ko}; some fonts that support CJK scripts have that spelled out in the style name part. @item pixels The font height, in pixels. @item height The font height on the screen, measured in tenths of a printer's point. This is the point size of the font, times ten. For a given vertical resolution, @var{height} and @var{pixels} are proportional; therefore, it is common to specify just one of them and use @samp{*} for the other. @item horiz The horizontal resolution, in pixels per inch, of the screen for which the font is intended. @item vert The vertical resolution, in pixels per inch, of the screen for which the font is intended. Normally the resolution of the fonts on your system is the right value for your screen; therefore, you normally specify @samp{*} for this and @var{horiz}. @item spacing This is @samp{m} (monospace), @samp{p} (proportional) or @samp{c} (character cell). @item width The average character width, in pixels, multiplied by ten. @item registry @itemx encoding The X font character set that the font depicts. (X font character sets are not the same as Emacs character sets, but they are similar.) You can use the @command{xfontsel} program to check which choices you have. Normally you should use @samp{iso8859} for @var{registry} and @samp{1} for @var{encoding}. @end table The fourth and final method of specifying a font is to use a font nickname. Certain fonts have shorter nicknames, which you can use instead of a normal font specification. For instance, @samp{6x13} is equivalent to @example -misc-fixed-medium-r-semicondensed--13-*-*-*-c-60-iso8859-1 @end example @cindex client-side fonts @cindex server-side fonts On X, Emacs recognizes two types of fonts: @dfn{client-side} fonts, which are provided by the Xft and Fontconfig libraries, and @dfn{server-side} fonts, which are provided by the X server itself. Most client-side fonts support advanced font features such as antialiasing and subpixel hinting, while server-side fonts do not. Fontconfig and GTK patterns match only client-side fonts. @cindex listing system fonts You will probably want to use a fixed-width default font---that is, a font in which all characters have the same width. For Xft and Fontconfig fonts, you can use the @command{fc-list} command to list the available fixed-width fonts, like this: @example fc-list :spacing=mono fc-list :spacing=charcell @end example @noindent For server-side X fonts, you can use the @command{xlsfonts} program to list the available fixed-width fonts, like this: @example xlsfonts -fn '*x*' | grep -E '^[0-9]+x[0-9]+' xlsfonts -fn '*-*-*-*-*-*-*-*-*-*-*-m*' xlsfonts -fn '*-*-*-*-*-*-*-*-*-*-*-c*' @end example @noindent Any font with @samp{m} or @samp{c} in the @var{spacing} field of the XLFD is a fixed-width font. To see what a particular font looks like, use the @command{xfd} command. For example: @example xfd -fn 6x13 @end example @noindent displays the entire font @samp{6x13}. While running Emacs, you can also set the font of a specific kind of text (@pxref{Faces}), or a particular frame (@pxref{Frame Parameters}). @node Speedbar @section Speedbar Frames @cindex speedbar @cindex attached frame (of speedbar) The @dfn{speedbar} is a special frame for conveniently navigating in or operating on another frame. The speedbar, when it exists, is always associated with a specific frame, called its @dfn{attached frame}; all speedbar operations act on that frame. Type @kbd{M-x speedbar} to create the speedbar and associate it with the current frame. To dismiss the speedbar, type @kbd{M-x speedbar} again, or select the speedbar and type @kbd{q}. (You can also delete the speedbar frame like any other Emacs frame.) If you wish to associate the speedbar with a different frame, dismiss it and call @kbd{M-x speedbar} from that frame. The speedbar can operate in various modes. Its default mode is @dfn{File Display} mode, which shows the files in the current directory of the selected window of the attached frame, one file per line. Clicking on a non-directory visits that file in the selected window of the attached frame, and clicking on a directory shows that directory in the speedbar (@pxref{Mouse References}). Each line also has a box, @samp{[+]} or @samp{<+>}, that you can click on to @dfn{expand} the contents of that item. Expanding a directory adds the contents of that directory to the speedbar display, underneath the directory's own line. Expanding an ordinary file adds a list of the tags in that file to the speedbar display; you can click on a tag name to jump to that tag in the selected window of the attached frame. When a file or directory is expanded, the @samp{[+]} changes to @samp{[-]}; you can click on that box to @dfn{contract} the item, hiding its contents. You navigate through the speedbar using the keyboard, too. Typing @key{RET} while point is on a line in the speedbar is equivalent to clicking the item on the current line, and @key{SPC} expands or contracts the item. @kbd{U} displays the parent directory of the current directory. To copy, delete, or rename the file on the current line, type @kbd{C}, @kbd{D}, and @kbd{R} respectively. To create a new directory, type @kbd{M}. Another general-purpose speedbar mode is @dfn{Buffer Display} mode; in this mode, the speedbar displays a list of Emacs buffers. To switch to this mode, type @kbd{b} in the speedbar. To return to File Display mode, type @kbd{f}. You can also change the display mode by clicking @kbd{mouse-3} anywhere in the speedbar window (or @kbd{mouse-1} on the mode-line) and selecting @samp{Displays} in the pop-up menu. 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. For more details on using and programming the speedbar, @xref{Top, Speedbar,,speedbar, Speedbar Manual}. @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. Each server also has its own selected frame. The commands you enter with a particular X server apply to that server's selected frame. @node Frame Parameters @section Frame Parameters @cindex default-frame-alist You can control the default appearance and behavior of all frames by specifying a default list of @dfn{frame parameters} in the variable @code{default-frame-alist}. Its value should be a list of entries, each specifying a parameter name and a value for that parameter. These entries take effect whenever Emacs creates a new frame, including the initial frame. @cindex frame size, specifying default For example, you can add the following lines to your init file (@pxref{Init File}) to set the default frame width to 90 character columns, the default frame height to 40 character rows, and the default font to @samp{Monospace-10}: @example (add-to-list 'default-frame-alist '(width . 90)) (add-to-list 'default-frame-alist '(height . 40)) (add-to-list 'default-frame-alist '(font . "Monospace-10")) @end example For a list of frame parameters and their effects, see @ref{Frame Parameters,,, elisp, The Emacs Lisp Reference Manual}. @cindex initial-frame-alist You can also specify a list of frame parameters which apply to just the initial frame, by customizing the variable @code{initial-frame-alist}. If Emacs is compiled to use an X toolkit, frame parameters that specify colors and fonts don't affect menus and the menu bar, since those are drawn by the toolkit and not directly by Emacs. Note that if you are using the desktop library to save and restore your sessions, the frames to be restored are recorded in the desktop file, together with their parameters. When these frames are restored, the recorded parameters take precedence over the frame parameters specified by @code{default-frame-alist} and @code{initial-frame-alist} in your init file. @xref{Saving Emacs Sessions}, for how to avoid that. @node Scroll Bars @section Scroll Bars @cindex Scroll Bar mode @cindex mode, Scroll Bar @cindex Vertical Scroll Bar On graphical displays, there is a @dfn{vertical scroll bar} on the side of each Emacs window. Clicking @kbd{mouse-1} on the scroll bar's up and down buttons scrolls the window by one line at a time. Clicking @kbd{mouse-1} above or below the scroll bar's inner box scrolls the window by nearly the entire height of the window, like @kbd{M-v} and @kbd{C-v} respectively (@pxref{Moving Point}). Dragging the inner box scrolls continuously. If Emacs is compiled on the X Window System without X toolkit support, the scroll bar behaves differently. Clicking @kbd{mouse-1} anywhere on the scroll bar scrolls forward like @kbd{C-v}, while @kbd{mouse-3} scrolls backward like @kbd{M-v}. Clicking @kbd{mouse-2} in the scroll bar lets you drag the inner box up and down. @findex scroll-bar-mode @findex toggle-scroll-bar To toggle the use of vertical scroll bars, type @kbd{M-x scroll-bar-mode}. This command applies to all frames, including frames yet to be created. To toggle vertical scroll bars for just the selected frame, use the command @kbd{M-x toggle-scroll-bar}. @vindex scroll-bar-mode To control the use of vertical scroll bars at startup, customize the variable @code{scroll-bar-mode}. Its value should be either @code{right} (put scroll bars on the right side of windows), @code{left} (put them on the left), or @code{nil} (disable vertical scroll bars). By default, Emacs puts scroll bars on the right if it was compiled with GTK+ support on the X Window System, and on MS-Windows or Mac OS; Emacs puts scroll bars on the left if compiled on the X Window System without GTK+ support (following the old convention for X applications). @vindex scroll-bar-width @cindex width of the vertical scroll bar You can also use the X resource @samp{verticalScrollBars} to enable or disable the scroll bars (@pxref{Resources}). To control the scroll bar width, change the @code{scroll-bar-width} frame parameter (@pxref{Frame Parameters,,, elisp, The Emacs Lisp Reference Manual}). @vindex scroll-bar-adjust-thumb-portion @cindex overscrolling If you're using Emacs on X (with GTK+ or Motif), you can customize the variable @code{scroll-bar-adjust-thumb-portion} to control @dfn{overscrolling} of the scroll bar, i.e., dragging the thumb down even when the end of the buffer is visible. If its value is non-@code{nil}, the scroll bar can be dragged downwards even if the end of the buffer is shown; if @code{nil}, the thumb will be at the bottom when the end of the buffer is shown. You can not over-scroll when the entire buffer is visible. @cindex scroll-bar face The visual appearance of the scroll bars is controlled by the @code{scroll-bar} face. @cindex vertical border On graphical frames, vertical scroll bars implicitly serve to separate side-by-side windows visually. When vertical scroll bars are disabled, Emacs by default separates such windows with the help of a one-pixel wide @dfn{vertical border}. That border occupies the first pixel column of the window on the right and may thus overdraw the leftmost pixels of any glyph displayed there. If these pixels convey important information, you can make them visible by enabling window dividers, see @ref{Window Dividers}. To replicate the look of vertical borders, set the @code{right-divider-width} parameter of frames to one and have the @code{window-divider} face inherit from that of @code{vertical-border}, @ref{Window Dividers,, Window Dividers, elisp, The Emacs Lisp Reference Manual}. @cindex Horizontal Scroll Bar @cindex Horizontal Scroll Bar mode On graphical displays with toolkit support, Emacs may also supply a @dfn{horizontal scroll bar} on the bottom of each window. Clicking @kbd{mouse-1} on that scroll bar's left and right buttons scrolls the window horizontally by one column at a time. Clicking @kbd{mouse-1} on the left or right of the scroll bar's inner box scrolls the window by four columns. Dragging the inner box scrolls the window continuously. Note that such horizontal scrolling can make the window's position of point disappear on the left or the right. Typing a character to insert text or moving point with a keyboard command will usually bring it back into view. @findex horizontal-scroll-bar-mode To toggle the use of horizontal scroll bars, type @kbd{M-x horizontal-scroll-bar-mode}. This command applies to all frames, including frames yet to be created. To toggle horizontal scroll bars for just the selected frame, use the command @kbd{M-x toggle-horizontal-scroll-bar}. @vindex horizontal-scroll-bar-mode To control the use of horizontal scroll bars at startup, customize the variable @code{horizontal-scroll-bar-mode}. @vindex scroll-bar-height @cindex height of the horizontal scroll bar You can also use the X resource @samp{horizontalScrollBars} to enable or disable horizontal scroll bars (@pxref{Resources}). To control the scroll bar height, change the @code{scroll-bar-height} frame parameter (@pxref{Frame Parameters,,, elisp, The Emacs Lisp Reference Manual}). @node Window Dividers @section Window Dividers @cindex Window Divider mode @cindex mode, Window Divider On graphical displays, you can use @dfn{window dividers} in order to separate windows visually. Window dividers are bars that can be dragged with the mouse, thus allowing you to easily resize adjacent windows. @findex window-divider-mode To toggle the display of window dividers, use the command @kbd{M-x window-divider-mode}. @vindex window-divider-default-places To customize where dividers should appear, use the option @code{window-divider-default-places}. Its value should be either @code{bottom-only} (to show dividers only on the bottom of windows), @code{right-only} (to show dividers only on the right of windows), or @code{t} (to show them on the bottom and on the right). @vindex window-divider-default-bottom-width @vindex window-divider-default-right-width To adjust the width of window dividers displayed by this mode customize the options @code{window-divider-default-bottom-width} and @code{window-divider-default-right-width}. When vertical scroll bars are disabled, dividers can be also useful to make the first pixel column of a window visible which would be otherwise covered by the vertical border used to separate side-by-side windows (@pxref{Scroll Bars}). For more details about window dividers see @ref{Window Dividers,, Window Dividers, elisp, The Emacs Lisp Reference Manual}. @node Drag and Drop @section Drag and Drop @cindex drag and drop In most graphical desktop environments, Emacs has basic support for @dfn{drag and drop} operations. For instance, dropping text onto an Emacs frame inserts the text where it is dropped. Dropping a file onto an Emacs frame visits that file. As a special case, dropping the file on a Dired buffer moves or copies the file (according to the conventions of the application it came from) into the directory displayed in that buffer. @vindex mouse-drag-and-drop-region Emacs can also optionally drag the region of text by mouse into another portion of this or another buffer. To enable that, customize the variable @code{mouse-drag-and-drop-region} to a non-nil value. Normally, the text is moved, i.e. cut and pasted, when the destination is the same buffer as the origin; dropping the region on another buffer copies the text instead. If the value of this variable names a modifier key, such as @samp{shift} or @samp{control} or @samp{alt}, then pressing that modifier key when dropping the text will copy it instead of cutting it, even if you drop on the same buffer as the one from which the text came. If you want to cut text even when source and destination buffers differ, set variable @code{mouse-drag-and-drop-region-cut-when-buffers-differ} to non-nil. If you do not want to see selected text in a tooltip in a graphic display and/or move point together with the mouse cursor during dragging, set @code{mouse-drag-and-drop-region-show-tooltip} and/or @code{mouse-drag-and-drop-region-show-cursor} to nil. @vindex dnd-open-file-other-window Dropping a file normally visits it in the window you drop it on. If you prefer to visit the file in a new window in such cases, customize the variable @code{dnd-open-file-other-window}. The XDND and Motif drag and drop protocols, and the old KDE 1.x protocol, are currently supported. @node Menu Bars @section Menu Bars @cindex Menu Bar mode @cindex mode, Menu Bar @findex menu-bar-mode @vindex menu-bar-mode You can toggle the use of menu bars with @kbd{M-x menu-bar-mode}. With no argument, this command toggles Menu Bar mode, a global minor mode. With an argument, the command turns Menu Bar mode on if the argument is positive, off if the argument is not positive. To control the use of menu bars at startup, customize the variable @code{menu-bar-mode}. @kindex C-mouse-3 @r{(when menu bar is disabled)} Expert users often turn off the menu bar, especially on text 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 pop-up menus. @xref{Menu Mouse Clicks}. @xref{Menu Bar}, for information on how to invoke commands with the menu bar. @xref{X Resources}, for how to customize the menu bar menus' visual appearance. @node Tool Bars @section Tool Bars @cindex Tool Bar mode @cindex mode, Tool Bar @cindex icons, toolbar On graphical displays, Emacs puts a @dfn{tool bar} at the top of each frame, just below the menu bar. This is a row of icons which you can click on with the mouse to invoke various commands. The global (default) tool bar contains general commands. Some major modes define their own tool bars; whenever a buffer with such a major mode is current, the mode's tool bar replaces the global tool bar. @findex tool-bar-mode @vindex tool-bar-mode To toggle the use of tool bars, type @kbd{M-x tool-bar-mode}. This command applies to all frames, including frames yet to be created. To control the use of tool bars at startup, customize the variable @code{tool-bar-mode}. @vindex tool-bar-style @cindex Tool Bar style When Emacs is compiled with GTK+ support, each tool bar item can consist of an image, or a text label, or both. By default, Emacs follows the Gnome desktop's tool bar style setting; if none is defined, it displays tool bar items as just images. To impose a specific tool bar style, customize the variable @code{tool-bar-style}. @cindex Tool Bar position You can also control the placement of the tool bar for the GTK+ tool bar with the frame parameter @code{tool-bar-position}. @xref{Frame Parameters,,, elisp, The Emacs Lisp Reference Manual}. NS builds consider the tool bar to be a window decoration, and therefore do not display it when a window is undecorated. @xref{Frame Parameters,,, elisp, The Emacs Lisp Reference Manual}. On macOS the tool bar is hidden when the frame is put into fullscreen, but can be displayed by moving the mouse pointer to the top of the screen. @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 that led to the question. To disable the use of dialog boxes, change the variable @code{use-dialog-box} to @code{nil}. In that case, Emacs always performs yes-or-no prompts using the echo area and keyboard input. This variable also controls whether to use file selection windows (but those are not supported on all platforms). @vindex use-file-dialog @cindex file selection dialog, how to disable A file selection window is a special kind of dialog box for asking for file names. You can customize the variable @code{use-file-dialog} to suppress the use of file selection windows, even if you still want other kinds of dialogs. This variable has no effect if you have suppressed all dialog boxes with the variable @code{use-dialog-box}. @vindex x-gtk-show-hidden-files @vindex x-gtk-file-dialog-help-text @cindex hidden files, in GTK+ file chooser @cindex help text, in GTK+ file chooser When Emacs is compiled with GTK+ support, it uses the GTK+ file chooser dialog. Emacs adds an additional toggle button to this dialog, which you can use to enable or disable the display of hidden files (files starting with a dot) in that dialog. If you want this toggle to be activated by default, change the variable @code{x-gtk-show-hidden-files} to @code{t}. In addition, Emacs adds help text to the GTK+ file chooser dialog; to disable this help text, change the variable @code{x-gtk-file-dialog-help-text} to @code{nil}. @node Tooltips @section Tooltips @cindex tooltips @dfn{Tooltips} are small special frames that display text information at the current mouse position. They activate when there is a pause in mouse movement over some significant piece of text in a window, or the mode line, or some other part of the Emacs frame such as a tool bar button or menu item. @findex tooltip-mode You can toggle the use of tooltips with the command @kbd{M-x tooltip-mode}. When Tooltip mode is disabled, the help text is displayed in the echo area instead. To control the use of tooltips at startup, customize the variable @code{tooltip-mode}. The following variables provide customization options for tooltip display: @vtable @code @item tooltip-delay This variable specifies how long Emacs should wait before displaying the first tooltip. The value is in seconds. @item tooltip-short-delay This variable specifies how long Emacs should wait before displaying subsequent tooltips on different items, having already displayed the first tooltip. The value is in seconds. @item tooltip-hide-delay The number of seconds since displaying a tooltip to hide it, if the mouse doesn't move. @item tooltip-x-offset @itemx tooltip-y-offset The X and Y offsets, in pixels, of the left top corner of the tooltip from the mouse pointer position. Note that these are ignored if @code{tooltip-frame-parameters} was customized to include, respectively, the @code{left} and @code{top} parameters. The values of the offsets should be chosen so that the tooltip doesn't cover the mouse pointer's hot spot, or it might interfere with clicking the mouse. @item tooltip-frame-parameters The frame parameters used for displaying tooltips. @xref{Frame Parameters,,, elisp, The Emacs Lisp Reference Manual}, and also @ref{Tooltips,,, elisp, The Emacs Lisp Reference Manual}. @end vtable For additional customization options for displaying tooltips, use @kbd{M-x customize-group @key{RET} tooltip @key{RET}}. @vindex x-gtk-use-system-tooltips If Emacs is built with GTK+ support, it displays tooltips via GTK+, using the default appearance of GTK+ tooltips. To disable this, change the variable @code{x-gtk-use-system-tooltips} to @code{nil}. If you do this, or if Emacs is built without GTK+ support, most attributes of the tooltip text are specified by the @code{tooltip} face, and by X resources (@pxref{X Resources}). @dfn{GUD tooltips} are special tooltips that show the values of variables when debugging a program with GUD@. @xref{Debugger Operation}. @node Mouse Avoidance @section Mouse Avoidance @cindex avoiding mouse in the way of your typing @cindex mouse avoidance On graphical terminals, the mouse pointer may obscure the text in the Emacs frame. Emacs provides two methods to avoid this problem. @vindex make-pointer-invisible Firstly, Emacs hides the mouse pointer each time you type a self-inserting character, if the pointer lies inside an Emacs frame; moving the mouse pointer makes it visible again. To disable this feature, set the variable @code{make-pointer-invisible} to @code{nil}. @vindex mouse-avoidance-mode Secondly, you can use Mouse Avoidance mode, a minor mode, to keep the mouse pointer away from point. To use Mouse Avoidance mode, customize the variable @code{mouse-avoidance-mode}. You can set this to various values to move the mouse in several ways: @table @code @item banish Move the pointer to a corner of the frame on any key-press. You can customize the variable @code{mouse-avoidance-banish-position} to specify where the pointer goes when it is banished. @item exile Banish the pointer 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 pointer, displace the pointer by a random distance and 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. Whenever Mouse Avoidance mode moves the mouse, it also raises the frame. @node Non-Window Terminals @section Non-Window Terminals @cindex text terminal On a text terminal, Emacs 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 in fact the frame's initial name. You can give frames more meaningful names 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 Text-Only Mouse @section Using a Mouse in Text Terminals @cindex mouse support @cindex terminal emulators, mouse support Some text terminals support mouse clicks in the terminal window. @cindex xterm In a terminal emulator which is compatible with @command{xterm}, you can use @kbd{M-x xterm-mouse-mode} to give Emacs control over simple uses of the mouse---basically, only non-modified single clicks are supported. Newer versions of @command{xterm} also support mouse-tracking. The normal @command{xterm} mouse functionality for such clicks is still available by holding down the @kbd{SHIFT} key when you press the mouse button. Xterm Mouse mode is a global minor mode (@pxref{Minor Modes}). Repeating the command turns the mode off again. @findex gpm-mouse-mode In the console on GNU/Linux, you can use @kbd{M-x gpm-mouse-mode} to enable mouse support. You must have the gpm server installed and running on your system in order for this to work. Note that when this mode is enabled, you cannot use the mouse to transfer text between Emacs and other programs which use GPM. This is due to limitations in GPM and the Linux kernel. @iftex @xref{MS-DOS Mouse,,,emacs-xtra,Specialized Emacs Features}, @end iftex @ifnottex @xref{MS-DOS Mouse}, @end ifnottex for information about mouse support on MS-DOS.