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This is Info file ../info/emacs, produced by Makeinfo-1.63 from the
input file emacs.texi.
File: emacs, Node: Change Window, Prev: Force Same Window, Up: Windows
Deleting and Rearranging Windows
================================
`C-x 0'
Delete the selected window (`delete-window'). That is a zero.
`C-x 1'
Delete all windows in the selected frame except the selected window
(`delete-other-windows').
`C-x ^'
Make selected window taller (`enlarge-window').
`C-x }'
Make selected window wider (`enlarge-window-horizontally').
`Drag-Mouse-1'
Dragging a window's mode line up or down with `Mouse-1' changes
window heights.
`Mouse-2'
`Mouse-2' in a window's mode line deletes all other windows in the
frame (`mouse-delete-other-windows').
`Mouse-3'
`Mouse-3' in a window's mode line deletes that window
(`mouse-delete-window').
To delete a window, type `C-x 0' (`delete-window'). (That is a
zero.) The space occupied by the deleted window is given to an
adjacent window (but not the minibuffer window, even if that is active
at the time). Once a window is deleted, its attributes are forgotten;
only restoring a window configuration can bring it back. Deleting the
window has no effect on the buffer it used to display; the buffer
continues to exist, and you can select it in any window with `C-x b'.
`C-x 1' (`delete-other-windows') is more powerful than `C-x 0'; it
deletes all the windows except the selected one (and the minibuffer);
the selected window expands to use the whole frame except for the echo
area.
You can also delete a window by clicking on its mode line with
`Mouse-2', and expand a window to fill its frame by clicking on its
mode line with `Mouse-3'.
The easiest way to adjust window heights is with a mouse. If you
press `Mouse-1' on a mode line, you can drag that mode line up or down,
changing the heights of the windows above and below it.
To readjust the division of space among vertically adjacent windows,
use `C-x ^' (`enlarge-window'). It makes the currently selected window
get one line bigger, or as many lines as is specified with a numeric
argument. With a negative argument, it makes the selected window
smaller. `C-x }' (`enlarge-window-horizontally') makes the selected
window wider by the specified number of columns. The extra screen
space given to a window comes from one of its neighbors, if that is
possible. If this makes any window too small, it is deleted and its
space is given to an adjacent window. The minimum size is specified by
the variables `window-min-height' and `window-min-width'.
*Note Minibuffer Edit::, for information about the Resize-Minibuffer
mode, which automatically changes the size of the minibuffer window to
fit the text in the minibuffer.
File: emacs, Node: Frames, Next: Major Modes, Prev: Windows, Up: Top
Frames and X Windows
********************
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.
* Menu:
* Mouse Commands:: Moving, cutting, and pasting, with the mouse.
* Secondary Selection::Cutting without altering point and mark.
* 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.
* 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.
* Menu Bars:: Enabling and disabling the menu bar.
* Faces:: How to change the display style using faces.
* Modifying Faces:: How to change what a particular face looks like.
* Font Lock:: Minor mode for syntactic highlighting using faces.
* Support Modes:: Font Lock support modes make Font Lock faster.
* Misc X:: Iconifying and deleting frames. Region highlighting.
* Non-Window Terminals:: Multiple frames on terminals that only show one.
File: emacs, Node: Mouse Commands, Next: Secondary Selection, Up: Frames
Mouse Commands for Editing
==========================
The mouse commands for selecting and copying a region are mostly
compatible with the `xterm' program. You can use the same mouse
commands for copying between Emacs and other X client programs.
`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. The number of lines scrolled
per step depends on how far away from the window edge the mouse
has gone; the variable `mouse-scroll-min-lines' specifies a
minimum step size.
`Mouse-2'
Yank the last killed text, where you click (`mouse-yank-at-click').
This is normally the middle button.
`Mouse-3'
This command, `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 `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 someplace else.
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 kill ring.
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. 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).
`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. *Note
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'. *Note Yanking::. However, if
`mouse-yank-at-point' is non-`nil', `Mouse-2' 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 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.
File: emacs, Node: Secondary Selection, Next: Mouse References, Prev: Mouse Commands, Up: Frames
Secondary Selection
===================
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 the screen.
`M-Mouse-1'
Set one endpoint for the "secondary selection"
(`mouse-start-secondary').
`M-Mouse-3'
Make a secondary selection, using the place specified with
`M-Mouse-1' as the other end (`mouse-secondary-save-then-kill').
A second click at the same place kills the secondary selection
just made.
`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 like `Mouse-1'.
If `mouse-yank-at-point' is non-`nil', `M-Mouse-2' yanks at point.
Then it does not matter precisely where you click; all that matters is
which window you click on. *Note Mouse Commands::.
File: emacs, Node: Mouse References, Next: Menu Mouse Clicks, Prev: Secondary Selection, Up: Frames
Following References with the Mouse
===================================
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 over it.
File: emacs, Node: Menu Mouse Clicks, Next: Mode Line Mouse, Prev: Mouse References, Up: Frames
Mouse Clicks for Menus
======================
Mouse clicks modified with the CONTROL and SHIFT keys bring up menus.
`C-Mouse-1'
This menu is for selecting a buffer.
`C-Mouse-2'
This menu is for specifying faces and other text properties for
editing formatted text. *Note Formatted Text::.
`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 may specify a different menu for this button.(1)
`S-mouse-1'
This menu is for specifying the frame's default font.
---------- Footnotes ----------
(1) Some systems use `Mouse-3' for a mode-specific menu. We took a
survey of users, and found they preferred to keep `Mouse-3' for
selecting and killing regions. Hence the decision to use `C-Mouse-3'
for this menu.
File: emacs, Node: Mode Line Mouse, Next: Creating Frames, Prev: Menu Mouse Clicks, Up: Frames
Mode Line Mouse Commands
========================
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. *Note Split Window::.
File: emacs, Node: Creating Frames, Next: Multiple Displays, Prev: Mode Line Mouse, Up: Frames
Creating Frames
===============
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 (*Note 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 `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
`switch-to-buffer-other-frame'.
`C-x 5 f FILENAME RET'
Visit file FILENAME and select its buffer in another frame. This
runs `find-file-other-frame'. *Note Visiting::.
`C-x 5 d DIRECTORY RET'
Select a Dired buffer for directory DIRECTORY in another frame.
This runs `dired-other-frame'. *Note Dired::.
`C-x 5 m'
Start composing a mail message in another frame. This runs
`mail-other-frame'. It is the other-frame variant of `C-x m'.
*Note 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-.'.
*Note Tags::.
`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'. *Note
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 `initial-frame-alist' to specify parameters that affect only
the initial frame. *Note Initial Parameters: (elisp)Initial
Parameters, for more information.
File: emacs, Node: Multiple Displays, Next: Special Buffer Frames, Prev: Creating Frames, Up: Frames
Multiple Displays
=================
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 (*note
Initial Options::.). To connect to another display, use the command
`make-frame-on-display':
`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!
File: emacs, Node: Special Buffer Frames, Next: Frame Parameters, Prev: Multiple Displays, Up: Frames
Special Buffer Frames
=====================
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,
(setq special-display-buffer-names
'("*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
automatically.
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.)
The variable `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
`special-display-buffer-names' or `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
`special-display-frame-alist'. Alternatively, it can have this form:
(FUNCTION ARGS...)
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.
File: emacs, Node: Frame Parameters, Next: Scroll Bars, Prev: Special Buffer Frames, Up: Frames
Setting Frame Parameters
========================
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 selected frame.
`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
`auto-raise-mode' 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.
The command `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.
`M-x set-default-font RET FONT RET'
Specify font FONT as the default for the selected frame. *Note
Font X::, 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 `S-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 (*note Resources X::.).
*Note Colors X::, regarding colors. *Note Font X::, regarding choice of
font.
For information on frame parameters and customization, see *Note
Frame Parameters: (elisp)Frame Parameters.
File: emacs, Node: Scroll Bars, Next: Menu Bars, Prev: Frame Parameters, Up: Frames
Scroll Bars
===========
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.
*Note Resources X::.
To enable or disable scroll bars for just the selected frame, use the
`M-x toggle-scroll-bar' command.
File: emacs, Node: Menu Bars, Next: Faces, Prev: Scroll Bars, Up: Frames
Menu Bars
=========
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.
When you are using a window system, you can use the mouse to choose a
command from the menu bar. On text-only terminals, you can use the menu
bar by typing `M-`' (`tmm-menubar'). This enters a mode in which you
can select a menu item from the keyboard. Either type the initial of
the item you want, or use the left and right arrow keys to choose an
item and use RET to finalize the choice.
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
interested in.
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. *Note Resources X::. Expert users often turn off the menu
bar, especially on text-only terminals where this makes one additional
line available for text.
File: emacs, Node: Faces, Next: Modifying Faces, Prev: Menu Bars, Up: Frames
Using Multiple Typefaces
========================
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 on MS-DOS supports faces partially by letting you
control the foreground and background colors of each face (*note
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. *Note Format Faces::, for how
to specify the font for text in the buffer. *Note Format Colors::, 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. *Note Display Vars::.
`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 (*note
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 named
`region'; you can control the style of highlighting by changing the
style of this face (*note Modifying Faces::.). *Note Transient Mark::,
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. *Note Font Lock::, for more information about Font Lock
mode and syntactic highlighting.
You can print out the buffer with the highlighting that appears on
your screen using the command `ps-print-buffer-with-faces'. *Note
Postscript::.
File: emacs, Node: Modifying Faces, Next: Font Lock, Prev: Faces, Up: Frames
Modifying Faces
===============
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. *Note Font X::, 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 font.
`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. *Note Resources X::.
File: emacs, Node: Font Lock, Next: Support Modes, Prev: Modifying Faces, Up: Frames
Font Lock mode
==============
Font Lock mode is a minor mode, always local to a particular buffer,
which highlights (or "fontifies") using various 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 defined or reserved keywords.
The command `M-x font-lock-mode' turns Font Lock mode on or off
according to the argument, and toggles the mode when it has no argument.
The function `turn-on-font-lock' 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 turn on Font Lock mode automatically in all modes which support
it, use the function `global-font-lock-mode', like this:
(global-font-lock-mode t)
In Font Lock mode, when you edit the text, the highlighting updates
automatically in the line that you changed. Most changes don't affect
the highlighting of subsequent lines, but occasionally they do. To
rehighlight a range of lines, use the command `C-M-g'
(`font-lock-fontify-block').
In certain major modes, `C-M-g' refontifies the entire current
function. (The variable `font-lock-mark-block-function' controls how
to find the current function.) In other major modes, `C-M-g'
refontifies 16 lines above and below point.
With a prefix argument N, `C-M-g' refontifies N lines above and
below point, regardless of the mode.
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
`font-lock-display-type' 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.
The variable `font-lock-maximum-decoration' specifies the preferred
level of fontification for modes that provide multiple levels. The
normal default is 1; larger numbers request more fontification, and
some modes support levels as high as 3. These variables can also
specify different numbers for particular major modes; for example, to
use level 3 for C/C++ modes, and the default level otherwise, use this:
(setq font-lock-maximum-decoration
'((c-mode . 3) (c++-mode . 3)))
Fontification can be too slow for large buffers, so you can suppress
it. The variable `font-lock-maximum-size' specifies a buffer size,
beyond which buffer fontification is suppressed.
File: emacs, Node: Support Modes, Next: Misc X, Prev: Font Lock, Up: Frames
Font Lock Support Modes
=======================
Font Lock support modes make Font Lock mode faster for large buffers.
There are two support modes: Fast Lock mode and Lazy Lock mode. They
use two different methods of speeding up Font Lock mode.
* Menu:
* Fast Lock Mode:: Saving font information in files.
* Lazy Lock Mode:: Fontifying only text that is actually displayed.
* Fast or Lazy:: Which support mode is best for you?
File: emacs, Node: Fast Lock Mode, Next: Lazy Lock Mode, Up: Support Modes
Fast Lock Mode
--------------
To make Font Lock mode faster for buffers visiting large files, you
can use Fast Lock mode. Fast Lock mode saves the font information for
each file in a separate cache file; each time you visit the file, it
rereads the font information from the cache file instead of refontifying
the text from scratch.
The command `M-x fast-lock-mode' turns Fast Lock mode on or off,
according to the argument (with no argument, it toggles). You can also
arrange to enable Fast Lock mode whenever you use Font Lock mode, like
this:
(setq font-lock-support-mode 'fast-lock-mode)
It is not worth writing a cache file for small buffers. Therefore,
the variable `fast-lock-minimum-size' specifies a minimum file size for
caching font information.
The variable `fast-lock-cache-directories' specifies where to put
the cache files. Its value is a list of directories to try; `"."'
means the same directory as the file being edited. The default value is
`("." "~/.emacs-flc")', which means to use the same directory if
possible, and otherwise the directory `~/.emacs-flc'.
The variable `fast-lock-save-others' specifies whether Fast Lock
mode should save cache files for files that you do not own. A
non-`nil' value means yes (and that is the default).
File: emacs, Node: Lazy Lock Mode, Next: Fast or Lazy, Prev: Fast Lock Mode, Up: Support Modes
Lazy Lock Mode
--------------
To make Font Lock mode faster for large buffers, you can use Lazy
Lock mode to reduce the amount of text that is fontified. In Lazy Lock
mode, buffer fontification is demand-driven; it happens to portions of
the buffer that are about to be displayed. And fontification of your
changes is deferred; it happens only when Emacs has been idle for a
certain short period of time.
The command `M-x lazy-lock-mode' turns Lazy Lock mode on or off,
according to the argument (with no argument, it toggles). You can also
arrange to enable Lazy Lock mode whenever you use Font Lock mode, like
this:
(setq font-lock-support-mode 'lazy-lock-mode)
It is not worth avoiding buffer fontification for small buffers.
Therefore, the variable `lazy-lock-minimum-size' specifies a minimum
buffer size for demand-driven buffer fontification. Buffers smaller
than that are fontified all at once, as in plain Font Lock mode.
When you alter the buffer, Lazy Lock mode defers fontification of the
text you changed. The variable `lazy-lock-defer-time' specifies how
many seconds Emacs must be idle before it starts fontifying your
changes. If the value is `nil', then changes are fontified
immediately, as in plain Font Lock mode.
Lazy Lock mode normally fontifies newly visible portions of the
buffer before they are first displayed. However, if the value of
`lazy-lock-defer-driven' is non-`nil', newly visible text is fontified
only when Emacs is idle for `lazy-lock-defer-time' seconds.
When Emacs is idle for a long time, Lazy Lock fontifies additional
portions of the buffer, not yet displayed, in case you will display them
later. This is called "stealth fontification".
The variable `lazy-lock-stealth-time' specifies how many seconds
Emacs has to be idle before stealth fontification starts. A value of
`nil' means no stealth fontification. The variables
`lazy-lock-stealth-lines' and `lazy-lock-stealth-verbose' specify the
granularity and verbosity of stealth fontification.
File: emacs, Node: Fast or Lazy, Prev: Lazy Lock Mode, Up: Support Modes
Fast Lock or Lazy Lock?
-----------------------
Here is a simple guide to help you choose one of the Font Lock
support modes.
* Fast Lock mode only intervenes during file visiting and buffer
killing (and related events); therefore buffer editing and window
scrolling are no faster or slower than plain Font Lock mode.
* Fast Lock mode is slower at reading a cache file than Lazy Lock
mode is at fontifying a window; therefore Fast Lock mode is slower
at visiting a file than Lazy Lock mode.
* Lazy Lock mode intervenes during window scrolling to fontify text
that scrolls onto the screen; therefore, scrolling is slower than
in plain Font Lock mode.
* Lazy Lock mode doesn't fontify during buffer editing (it defers
fontification of changes); therefore, editing is faster than in
plain Font Lock mode.
* Fast Lock mode can be fooled by a file that is kept under version
control software; therefore buffer fontification may occur even
when a cache file exists for the file.
* Fast Lock mode only works with a buffer visiting a file; Lazy Lock
mode works with any buffer.
* Fast Lock mode generates cache files; Lazy Lock mode does not.
The variable `font-lock-support-mode' specifies which of these
support modes to use; for example, to specify that Fast Lock mode is
used for C/C++ modes, and Lazy Lock mode otherwise, set the variable
like this:
(setq font-lock-support-mode
'((c-mode . fast-lock-mode) (c++-mode . fast-lock-mode)
(t . lazy-lock-mode)))
File: emacs, Node: Misc X, Next: Non-Window Terminals, Prev: Support Modes, Up: Frames
Miscellaneous X Window Features
===============================
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.
`C-x 5 o'
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.
`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'.
*Note Mark::.
File: emacs, Node: Non-Window Terminals, Prev: Misc X, Up: Frames
Non-Window 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 `C-x 5 2' to create a new frame and switch to it; use `C-x 5 o'
to cycle through the existing frames; use `C-x 5 0' to delete the
current frame.
Each frame has a number to distinguish it. The selected frame's
number appears in the mode line after `Emacs', except when frame 1 is
selected.
File: emacs, Node: Major Modes, Next: Indentation, Prev: Frames, Up: Top
Major Modes
***********
Emacs provides many alternative "major modes", each of which
customizes Emacs for editing text of a particular sort. The major modes
are mutually exclusive, and each buffer has one major mode at any time.
The mode line normally shows the name of the current major mode, in
parentheses (*note Mode Line::.).
The least specialized major mode is called "Fundamental mode". This
mode has no mode-specific redefinitions or variable settings, so that
each Emacs command behaves in its most general manner, and each option
is in its default state. For editing text of a specific type that
Emacs knows about, such as Lisp code or English text, you should switch
to the appropriate major mode, such as Lisp mode or Text mode.
Selecting a major mode changes the meanings of a few keys to become
more specifically adapted to the language being edited. The ones which
are changed frequently are TAB, DEL, and LFD. The prefix key `C-c'
normally contains mode-specific commands. In addition, the commands
which handle comments use the mode to determine how comments are to be
delimited. Many major modes redefine the syntactical properties of
characters appearing in the buffer. *Note Syntax::.
The major modes fall into three major groups. Lisp mode (which has
several variants), C mode, Fortran mode and others are for specific
programming languages. Text mode, Nroff mode, TeX mode and Outline
mode are for editing English text. The remaining major modes are not
intended for use on users' files; they are used in buffers created for
specific purposes by Emacs, such as Dired mode for buffers made by Dired
(*note Dired::.), and Mail mode for buffers made by `C-x m' (*note
Sending Mail::.), and Shell mode for buffers used for communicating
with an inferior shell process (*note Interactive Shell::.).
Most programming language major modes specify that only blank lines
separate paragraphs. This is to make the paragraph commands useful.
(*Note Paragraphs::.) They also cause Auto Fill mode to use the
definition of TAB to indent the new lines it creates. This is because
most lines in a program are usually indented. (*Note Indentation::.)
* Menu:
* Choosing Modes:: How major modes are specified or chosen.
File: emacs, Node: Choosing Modes, Prev: Major Modes, Up: Major Modes
How Major Modes are Chosen
==========================
You can select a major mode explicitly for the current buffer, but
most of the time Emacs determines which mode to use based on the file
name or on special text in the file.
Explicit selection of a new major mode is done with a `M-x' command.
From the name of a major mode, add `-mode' to get the name of a command
to select that mode. Thus, you can enter Lisp mode by executing `M-x
lisp-mode'.
When you visit a file, Emacs usually chooses the right major mode
based on the file's name. For example, files whose names end in `.c'
are edited in C mode. The correspondence between file names and major
modes is controlled by the variable `auto-mode-alist'. Its value is a
list in which each element has this form,
(REGEXP . MODE-FUNCTION)
or this form,
(REGEXP MODE-FUNCTION FLAG)
For example, one element normally found in the list has the form
`("\\.c\\'" . c-mode)', and it is responsible for selecting C mode for
files whose names end in `.c'. (Note that `\\' is needed in Lisp
syntax to include a `\' in the string, which is needed to suppress the
special meaning of `.' in regexps.) If the element has the form
`(REGEXP MODE-FUNCTION FLAG)' and FLAG is non-nil, then after calling
FUNCTION, the suffix that matched REGEXP is deleted and the list is
searched again for another match.
You can specify which major mode should be used for editing a certain
file by a special sort of text in the first nonblank line of the file.
The mode name should appear in this line both preceded and followed by
`-*-'. Other text may appear on the line as well. For example,
;-*-Lisp-*-
tells Emacs to use Lisp mode. Such an explicit specification overrides
any defaulting based on the file name. Note how the semicolon is used
to make Lisp treat this line as a comment.
Another format of mode specification is
-*-Mode: MODENAME;-*-
which allows you to specify local variables as well, like this:
-*- mode: MODENAME; VAR: VALUE; ... -*-
*Note File Variables::, for more information about this.
When a file's contents begin with `#!', it can serve as an
executable shell command, which works by running an interpreter named on
the file's first line. The rest of the file is used as input to the
interpreter.
When you visit such a file in Emacs, if the file's name does not
specify a major mode, Emacs uses the interpreter name on the first line
to choose a mode. If the first line is the name of a recognized
interpreter program, such as `perl' or `tcl', Emacs uses a mode
appropriate for programs for that interpreter. The variable
`interpreter-mode-alist' specifies the correspondence between
interpreter program names and major modes.
When you visit a file that does not specify a major mode to use, or
when you create a new buffer with `C-x b', the variable
`default-major-mode' specifies which major mode to use. Normally its
value is the symbol `fundamental-mode', which specifies Fundamental
mode. If `default-major-mode' is `nil', the major mode is taken from
the previously selected buffer.
If you change the major mode of a buffer, you can go back to the
major mode Emacs would choose automatically: use the command `M-x
normal-mode' to do this. This is the same function that `find-file'
calls to choose the major mode. It also processes the file's local
variables list if any.