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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 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 C-x C-c in one
frame, it terminates all the frames. To delete just one
frame, use 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.
The mouse commands for selecting and copying a region are mostly compatible with the
program. You can use the same mouse commands for copying between Emacs and other X client
- Mouse-1 Move point to where you click (
mouse-set-point). This is normally the left button.
- Drag-Mouse-1 Set the region to the text you select by dragging, and copy it to the kill ring
mouse-set-region). You can specify both
ends of the region with this single command.
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.
Mouse-2 Yank the last killed text, where you
mouse-yank-at-click). This is normally the middle button.
Mouse-3 This command,
has several functions depending on where you click and the status of the region.
The most basic case is when you click Mouse-1 in one place and then 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
If you click Mouse-1, scroll with the scroll bar, and then click Mouse-3,
it remembers where point was before scrolling (where you put it with 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,
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, 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
If you originally specified the region using a
double or triple Mouse-1, so that the region
is defined to consist of entire words or lines, then adjusting the region with Mouse-3 also proceeds by entire
words or lines.
If you use Mouse-3 a second time consecutively, at the same place, that
kills the region already selected.
Double-Mouse-1 This key sets the region
around the word which you click on.
Double-Drag-Mouse-1 This key selects a region
made up of the words that you drag across.
Triple-Mouse-1 This key sets the region
around the line which you click on.
Triple-Drag-Mouse-1 This key selects a region
made up of the lines that you drag across.
The simplest way to kill text with the mouse is to
press Mouse-1 at one end, then press Mouse-3 twice at the other end.
See section Deletion and Killing. To copy the text into the kill ring without deleting it from the buffer, press Mouse-3 just once---or just drag
across the text with Mouse-1. Then you can
copy it elsewhere by yanking it.
To yank the killed or copied text somewhere else,
move the mouse there and press Mouse-2. See section Yanking. However, if
mouse-yank-at-point is non-
yanks at point. Then it does not matter precisely
where you click; all that matters is which window you
click on. The default value is
nil. This variable
also effects yanking the secondary selection.
To copy text to another X window, kill it or save it in the kill ring. Under X,
this also sets the 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 C-y or Mouse-2.
When Emacs puts text into the kill ring, or rotates
text to the front of the kill ring, it sets the 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 (
x-cut-buffer-max specifies the maximum number of
characters); putting long strings in the cut buffer can
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.
The 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.
- 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 (
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
M-Mouse-1 Set one endpoint for the secondary selection (
M-Mouse-3 Make a secondary selection, using
the place specified with M-Mouse-1 as the other end (
A second click at the same place kills the secondary selection
M-Mouse-2 Insert the secondary selection
where you click (
mouse-kill-secondary). This places point at the end of the yanked text.
Double or triple clicking of M-Mouse-1 operates on words and lines, much
mouse-yank-at-point is non-
M-Mouse-2 yanks at point. Then it does not
matter precisely where you click; all that matters is which window you click on. See section Mouse Commands for Editing.
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 Mouse-2 specially,
as a command to use or view the item you click on.
For example, if you click Mouse-2 on a file name in a Dired buffer, you visit
the that file. If you click Mouse-2 on an error
message in the *Compilation*
buffer, you go to the source code for that error message. If you
click Mouse-2 on a completion in the *Completions*
buffer, you choose that completion.
You can usually tell when Mouse-2 has this special sort of meaning because
the sensitive text highlights when you move the mouse
Mouse clicks modified with the CONTROL bring up menus.
- C-Mouse-1 This menu is for specifying the frame's
- C-Mouse-2 This menu is for specifying faces and other text properties for editing formatted text. See section Editing
C-Mouse-3 This menu is mode-specific. For most modes, this
menu has the same items as all the mode-specific menu bar menus put together. Some modes
You can use mouse clicks on window mode lines to
select and manipulate windows.
- Mouse-1 Mouse-1 on a mode line selects the window above. By dragging Mouse-1 on the mode
line, you can move it, thus changing the height of the windows above and below.
- Mouse-2 Mouse-2 on a mode line expands that window to fill its frame.
Mouse-3 Mouse-3 on a mode line deletes the window above.
C-Mouse-2 C-Mouse-2 on a mode line splits the window above horizontally, above the place in the mode
line where you click.
C-Mouse-2 on a scroll bar splits the corresponding window vertically. See section Splitting Windows.
The prefix key C-x 5 is analogous to C-x 4, with parallel
subcommands. The difference is that C-x 5 commands create a new frame rather than just a new window in the selected frame
(See section Displaying in Another 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 C-x 5 commands differ in how they find or create the buffer to select:
- C-x 5 2 Create a new frame (
make-frame). C-x 5 b bufname RET
Select buffer bufname in another window. This runs
C-x 5 f filename RET Visit file filename and
select its buffer in another frame. This runs
find-file-other-frame. See section Visiting
Files. C-x 5 d directory RET
Select a Dired buffer
for directory directory
in another frame. This runs
See section Dired, the Directory Editor. C-x 5 m
Start composing a mail message
in another frame. This runs
It is the other-frame variant of C-x m. See
section Sending Mail. C-x 5 . Find a tag in the
current tag table in another frame. This runs
find-tag-other-frame, the multiple-frame
variant of M-.. See section Tags Tables. C-x
5 r filename RET Visit file filename read-only, and
select its buffer in another frame. This runs
find-file-read-only-other-frame. See section Visiting
You can control the appearance of new frames you create by setting the frame parameters in
default-frame-alist. You can use the variable
to specify parameters that affect only the initial frame.
See section 'Initial Parameters' in The Emacs Lisp Manual, for more
A single Emacs can talk to more than one X Windows display. Initially, Emacs uses just
one display---the one specified with the
DISPLAY environment variable or with the --display option (see section Initial
Options). To connect to another display, use the command
- M-x make-frame-on-display RET display
RET Create a new frame on display display.
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 C-x
C-c, that exits the Emacs job for all of them!
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
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,
'("*Completions*" "*grep*" "*tex-shell*"))
then completion lists,
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
More generally, you can set
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.)
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
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
special-display-frame-alist. Alternatively, it can have this form:
where function is a symbol. Then the frame
is constructed by calling function; its first argument is the buffer, and its remaining arguments are args.
This section describes commands for altering the display style and window management behavior of the selected frame.
- M-x set-foreground-color RET color RET Specify
color color for the foreground of the selected frame.
- M-x set-background-color RET color RET Specify
color color for the background of the selected frame.
This changes the foreground color of the
modeline face also, so that it
remains in inverse video compared with the default.
M-x set-cursor-color RET color RET
Specify color color for the cursor of the
M-x set-mouse-color RET color RET Specify color
color for the mouse cursor when it is over
the selected frame.
M-x set-border-color RET color RET Specify
color color for the border of the selected frame.
M-x list-colors-display Display the defined
color names and show what the colors look like. This command
is somewhat slow.
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
has no effect on it.
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 of the frame, the frame moves to the bottom of the stack of X windows.
auto-lower-mode has no
effect on auto-lower implemented by the X window
manager. To control that, you must use the appropriate window
M-x set-default-font RET font RET Specify font font
as the default for the selected frame. See section Font Specification Options, for ways to list the available fonts on your system.
You can also set a frame's default font through a
pop-up menu. Press C-Mouse-1 to activate this menu.
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 (see section X Resources). See section Window
Color Options, regarding colors. See section Font
Specification Options, regarding choice of font.
For information on frame parameters and customization, see section 'Frame
Parameters' in The Emacs Lisp Manual.
When using X, Emacs normally makes a scroll bar at the right of each Emacs window. 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 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. Mouse-1
(normally, the left button) moves the line at the level where you click up to the top of
the window. 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.
Aside from scrolling, you can also click C-Mouse-2
in the scroll bar to split a window vertically. The
split occurs on the line where you click.
You can enable or disable Scroll Bar mode with the command
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. You can use the X resource verticalScrollBars to control the initial
setting of Scroll Bar mode. See section X Resources.
To enable or disable scroll bars for just the selected frame,
use the M-x toggle-scroll-bar command.
By default, each Emacs frame has a menu bar at the
top which you can use to perform certain common operations. There's no need to describe
them in detail here, as you can more easily see for yourself; also, we may change them and
add to them in subsequent Emacs versions.
Each of the operations in the menu bar is bound to an ordinary Emacs command which you can invoke equally well with M-x
or with its own key bindings. The menu lists one equivalent key binding (if the command
has any) at the right margin. To see the command's name
and documentation, type C-h k and then select the menu bar item you are
You can turn display of menu bars on or off with M-x 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 menuBarLines to control the initial setting of Menu Bar mode. See
section X Resources.
When using Emacs with X, you can set up multiple styles of displaying characters. The
aspects of style that you can control are the type font, the foreground color, the
background color, and whether to underline. Emacs 19.29 does not support faces on MS-DOS,
but future versions may support them partially (see section MS-DOS
The way you control display style is by defining named faces. Each face can
specify a type font, a foreground color, a background color, and an underline flag; but it
does not have to specify all of them.
The style of display used for a given character in
the text is determined by combining several faces. Any
aspect of the display style that isn't specified by overlays or text properties comes from the frame itself.
Enriched mode, the mode for editing formatted text,
includes several commands and menus for specifying faces. See section Faces in Formatted Text, for how to specify the font for text in the buffer.
See section Colors in Formatted Text, for how to specify
the foreground and background color.
To see what faces are currently defined, and what they look like, type M-x list-faces-display. It's possible for a given face
to look different in different frames; this command
shows the appearance in the frame in which you type it.
Here's a list of the standardly defined faces:
- default This face is used for ordinary text
that doesn't specify any other face. modeline This face is used for mode lines. By
default, it's set up as the inverse of the default face. See section Variables Controlling Display. highlight This face is
used for highlighting portions of text, in various modes. region
This face is used for displaying a selected region
(when Transient Mark mode is enabled---see below). secondary-selection This face is used for displaying a
secondary selection (see section Secondary Selection). bold This face uses a bold
variant of the default font, if it has one. italic This face uses an italic variant
of the default font, if it has one. bold-italic This face uses a bold italic
variant of the default font, if it has one. underline This face underlines text.
When Transient Mark mode is enabled, the text of the region is
highlighted when the mark is active. This uses the face
region; you can control the style
of highlighting by changing the style of this face (see
section Modifying Faces). See section Transient Mark Mode, for more information about Transient Mark mode and activation and deactivation of the mark.
One easy way to use faces is to turn on Font-Lock mode. This minor mode, which is
always local to a particular buffer, arranges to choose faces according to the syntax
of the text you are editing. It can recognize comments
and strings in most languages; in several languages, it can also recognize and properly
highlight various other important constructs---for example, names of functions being
Font-Lock mode is a minor mode. The command M-x
font-lock-mode turns the mode on or off. The function
unconditionally enables Font-Lock mode. This is useful in mode-hook functions. For
example, to enable Font-Lock mode whenever you edit a C file, you can do this:
(add-hook 'c-mode-hook 'turn-on-font-lock)
To get the full benefit of Font-Lock mode, you need to choose a default font which has
bold, italic, and bold-italic variants; or else you need to have a color or grayscale
screen. The variable
specifies whether Font-Lock mode should use font styles, colors, or shades of gray to
distinguish the various kinds of text. Emacs chooses
the default value according to the characteristics of your display.
Here are the commands for changing the font of a face:
- M-x set-face-font RET face RET font RET
Change face face to use font font. See section Font Specification Options, for more information about font
naming under X.
- M-x make-face-bold RET face RET Convert face face
to use a bold version of its current font.
M-x make-face-italic RET face
RET Convert face face to use a italic version of its current
M-x make-face-bold-italic RET face RET Convert
face face to use a bold-italic version of its current font.
M-x make-face-unbold RET face RET Convert face face
to use a non-bold version of its current font.
M-x make-face-unitalic RET face RET Convert
face face to use a non-italic version of its current font.
Here are the commands for setting the colors and underline flag of a face:
- M-x set-face-foreground RET face RET color
RET Use color color for the foreground of characters in face face.
- M-x set-face-background RET face RET color
RET Use color color for the background of characters in face face.
On a black-and-white display, the colors you can use for the background are black,
white, gray, gray1 and gray3. Emacs
supports the gray colors by using background stipple patterns instead of a color.
M-x set-face-stipple RET face RET pattern
RET Use stipple pattern pattern for the background of characters
in face face.
M-x list-colors-display Display the defined
color names and show what the colors look like.
M-x set-face-underline-p RET face RET flag
RET Specify whether to underline characters in face face.
M-x invert-face RET face RET Swap the
foreground and background colors of face face.
M-x modify-face RET face RET attributes...
Change various attributes of face face. This command
prompts for all the attribute of the face, one attribute at a time. For the color and
stipple attributes, the attribute's current value is the default---type just RET
if you don't want to change that attribute. Type none if you want to clear
out the attribute.
You can also use X resources to specify attributes of particular faces. See section X Resources.
The following commands let you create, delete and operate on frames:
- C-z To iconify the selected Emacs frame, type C-z
iconify-or-deiconify-frame). The normal
meaning of 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.
C-x 5 0 To delete the selected frame, type C-x 5 0 (
delete-frame). This is not allowed if there is only one frame.
M-x transient-mark-mode Under X Windows, when
Transient Mark mode is enabled, Emacs highlights the region when the mark
is active. This feature is the main motive for using Transient Mark mode. To toggle the state of this mode, use the command M-x transient-mark-mode.
See section The Mark and the Region.