@c This is part of the Emacs manual.
-@c Copyright (C) 1985, 86, 87, 93, 94, 95, 97, 2000 Free Software Foundation, Inc.
+@c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 2000, 2001,
+@c 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
@c See file emacs.texi for copying conditions.
@node Basic, Minibuffer, Exiting, Top
@chapter Basic Editing Commands
then if you type @kbd{XX}, you get @samp{FOOXXBAR}, with the cursor
still before the @samp{B}.
- To @dfn{delete} text you have just inserted, use @key{DEL}. @key{DEL}
-deletes the character @emph{before} the cursor (not the one that the cursor
-is on top of or under; that is the character @var{after} the cursor). The
-cursor and all characters after it move backwards. Therefore, if you type
-a printing character and then type @key{DEL}, they cancel out.
+ To @dfn{delete} text you have just inserted, use the large key
+labeled @key{DEL}, @key{BACKSPACE} or @key{DELETE} which is a short
+distance above the @key{RET} or @key{ENTER} key. This is the key you
+normally use, outside Emacs, for erasing the last character that you
+typed. Regardless of the label on that key, Emacs thinks of it as
+@key{DEL}, and that's what we call it in this manual.
+
+ The @key{DEL} key deletes the character @emph{before} the cursor.
+As a consequence, the cursor and all the characters after it move
+backwards. If you type a printing character and then type @key{DEL},
+they cancel out.
+
+ On most computers, Emacs recognizes automatically which key ought to
+be @key{DEL}, and sets it up that way. But in some cases, especially
+with text-only terminals, you will need to tell Emacs which key to use
+for that purpose. If the large key not far above the @key{RET} or
+@key{ENTER} key doesn't delete backwards, you need to do this.
+@xref{DEL Does Not Delete}, for an explanation of how.
+
+ Most PC keyboards have both a @key{BACKSPACE} key a short ways above
+@key{RET} or @key{ENTER}, and a @key{DELETE} key elsewhere. On these
+keyboards, Emacs supports when possible the usual convention that the
+@key{BACKSPACE} key deletes backwards (it is @key{DEL}), while the
+@key{DELETE} key deletes ``forwards,'' deleting the character after
+point, the one underneath the cursor, like @kbd{C-d} (see below).
@kindex RET
@cindex newline
To end a line and start typing a new one, type @key{RET}. This
inserts a newline character in the buffer. If point is in the middle of
-a line, @key{RET} splits the line. Typing @key{DEL} when the cursor is
+a line, the effect is to split the line. Typing @key{DEL} when the cursor is
at the beginning of a line deletes the preceding newline, thus joining
the line with the preceding line.
@item
@kbd{C-q} followed by a sequence of octal digits inserts the character
with the specified octal character code. You can use any number of
-octal digits; any non-digit terminates the sequence. If the terminating
-character is @key{RET}, it serves only to terminate the sequence; any
-other non-digit is itself used as input after terminating the sequence.
-(The use of octal sequences is disabled in ordinary non-binary Overwrite
-mode, to give you a convenient way to insert a digit instead of
-overwriting with it.)
+octal digits; any non-digit terminates the sequence. If the
+terminating character is @key{RET}, it serves only to terminate the
+sequence. Any other non-digit terminates the sequence and then acts
+as normal input---thus, @kbd{C-q 1 0 1 B} inserts @samp{AB}.
+
+The use of octal sequences is disabled in ordinary non-binary
+Overwrite mode, to give you a convenient way to insert a digit instead
+of overwriting with it.
@end itemize
@cindex 8-bit character codes
@section Changing the Location of Point
@cindex arrow keys
-@kindex LEFT
-@kindex RIGHT
-@kindex UP
-@kindex DOWN
@cindex moving point
@cindex movement
@cindex cursor motion
@kindex M->
@kindex M-<
@kindex M-r
-@findex beginning-of-line
-@findex end-of-line
+@kindex LEFT
+@kindex RIGHT
+@kindex UP
+@kindex DOWN
+@findex move-beginning-of-line
+@findex move-end-of-line
@findex forward-char
@findex backward-char
@findex next-line
@findex move-to-window-line
@table @kbd
@item C-a
-Move to the beginning of the line (@code{beginning-of-line}).
+Move to the beginning of the line (@code{move-beginning-of-line}).
@item C-e
-Move to the end of the line (@code{end-of-line}).
+Move to the end of the line (@code{move-end-of-line}).
@item C-f
-Move forward one character (@code{forward-char}).
+Move forward one character (@code{forward-char}). The right-arrow key
+does the same thing.
@item C-b
-Move backward one character (@code{backward-char}).
+Move backward one character (@code{backward-char}). The left-arrow
+key has the same effect.
@item M-f
Move forward one word (@code{forward-word}).
@item M-b
@item C-n
Move down one line, vertically (@code{next-line}). This command
attempts to keep the horizontal position unchanged, so if you start in
-the middle of one line, you end in the middle of the next.
+the middle of one line, you end in the middle of the next. The
+down-arrow key does the same thing.
@item C-p
-Move up one line, vertically (@code{previous-line}).
+Move up one line, vertically (@code{previous-line}). The up-arrow key
+has the same effect.
@item M-r
Move point to left margin, vertically centered in the window
(@code{move-to-window-line}). Text does not move on the screen.
@xref{Arguments}, for more information on numeric arguments.@refill
@item M->
Move to the end of the buffer (@code{end-of-buffer}).
+@item C-v
+@itemx @key{PAGEDOWN}
+@itemx @key{PRIOR}
+Scroll the display one screen forward, and move point if necessary to
+put it on the screen (@code{scroll-up}). This doesn't always move
+point, but it is commonly used to do so. If your keyboard has a
+@key{PAGEDOWN} or @key{PRIOR} key, it does the same thing.
+
+Scrolling commands are further described in @ref{Scrolling}.
+@item M-v
+@itemx @key{PAGEUP}
+@itemx @key{NEXT}
+Scroll one screen backward, and move point if necessary to put it on
+the screen (@code{scroll-down}). This doesn't always move point, but
+it is commonly used to do so. If your keyboard has a @key{PAGEUP} or
+@key{NEXT} key, it does the same thing.
@item M-x goto-char
Read a number @var{n} and move point to buffer position @var{n}.
Position 1 is the beginning of the buffer.
-@item M-x goto-line
-Read a number @var{n} and move point to line number @var{n}. Line 1
-is the beginning of the buffer.
+@item M-g M-g
+@itemx M-g g
+@itemx M-x goto-line
+Read a number @var{n} and move point to the beginning of line number
+@var{n}. Line 1 is the beginning of the buffer. If point is on or
+just after a number, then that is the default for @var{n}, if you just
+press @key{RET} with an empty minibuffer.
@item C-x C-n
@findex set-goal-column
@kindex C-x C-n
@vindex track-eol
If you set the variable @code{track-eol} to a non-@code{nil} value,
-then @kbd{C-n} and @kbd{C-p} when at the end of the starting line move
+then @kbd{C-n} and @kbd{C-p}, when starting at the end of the line, move
to the end of another line. Normally, @code{track-eol} is @code{nil}.
@xref{Variables}, for how to set variables such as @code{track-eol}.
@vindex next-line-add-newlines
- @kbd{C-n} normally gets an error when you use it on the last line of
-the buffer (just as @kbd{C-p} gets an error on the first line). But
-if you set the variable @code{next-line-add-newlines} to a
-non-@code{nil} value, @kbd{C-n} on the last line of a buffer creates
-an additional line at the end and moves down onto it.
+ @kbd{C-n} normally stops at the end of the buffer when you use it on
+the last line of the buffer. But if you set the variable
+@code{next-line-add-newlines} to a non-@code{nil} value, @kbd{C-n} on
+the last line of a buffer creates an additional line at the end and
+moves down onto it.
-@node Erasing
+@node Erasing
@section Erasing Text
@table @kbd
Delete the character before point (@code{delete-backward-char}).
@item C-d
Delete the character after point (@code{delete-char}).
+@item @key{DELETE}
+@itemx @key{BACKSPACE}
+One of these keys, whichever is the large key above the @key{RET} or
+@key{ENTER} key, deletes the character before point, like @key{DEL}.
+If that is @key{BACKSPACE}, and your keyboard also has @key{DELETE},
+then @key{DELETE} deletes forwards, like @kbd{C-d}.
@item C-k
Kill to the end of the line (@code{kill-line}).
@item M-d
@item C-x u
Undo one batch of changes---usually, one command worth (@code{undo}).
@item C-_
+@itemx C-/
The same.
@item C-u C-x u
Undo one batch of changes in the region.
@kindex C-x u
@kindex C-_
+@kindex C-/
@findex undo
- The command @kbd{C-x u} or @kbd{C-_} is how you undo. The first time
-you give this command, it undoes the last change. Point moves back to
-where it was before the command that made the change.
+ The command @kbd{C-x u} (or @kbd{C-_} or @kbd{C-/}) is how you undo.
+The first time you give this command, it undoes the last change.
+Point moves back to where it was before the command that made the
+change.
Consecutive repetitions of @kbd{C-_} or @kbd{C-x u} undo earlier and
earlier changes, back to the limit of the undo information available.
If all recorded changes have already been undone, the undo command
-prints an error message and does nothing.
+displays an error message and does nothing.
+@findex undo-only
Any command other than an undo command breaks the sequence of undo
commands. Starting from that moment, the previous undo commands become
ordinary changes that you can undo. Thus, to redo changes you have
undone, type @kbd{C-f} or any other command that will harmlessly break
-the sequence of undoing, then type more undo commands.
+the sequence of undoing, then type more undo commands. On the other
+hand, if you want to ignore previous undo commands, use @kbd{M-x
+undo-only}. This is like @code{undo}, but will not redo changes
+you have just undone.
@cindex selective undo
@kindex C-u C-x u
Ordinary undo applies to all changes made in the current buffer. You
-can also perform @dfn{selective undo}, limited to the current region.
+can also perform @dfn{selective undo}, limited to the current region
+(@pxref{Mark}).
To do this, specify the region you want, then run the @code{undo}
command with a prefix argument (the value does not matter): @kbd{C-u C-x
u} or @kbd{C-u C-_}. This undoes the most recent change in the region.
To undo further changes in the same region, repeat the @code{undo}
-command (no prefix argument is needed). In Transient Mark mode, any use
-of @code{undo} when there is an active region performs selective undo;
-you do not need a prefix argument.
+command (no prefix argument is needed). In Transient Mark mode
+(@pxref{Transient Mark}), any use of @code{undo} when there is an
+active region performs selective undo; you do not need a prefix
+argument.
If you notice that a buffer has been modified accidentally, the
easiest way to recover is to type @kbd{C-_} repeatedly until the stars
@vindex undo-limit
@vindex undo-strong-limit
+@vindex undo-outer-limit
@cindex undo limit
When the undo information for a buffer becomes too large, Emacs
discards the oldest undo information from time to time (during garbage
collection). You can specify how much undo information to keep by
-setting two variables: @code{undo-limit} and @code{undo-strong-limit}.
-Their values are expressed in units of bytes of space.
+setting three variables: @code{undo-limit}, @code{undo-strong-limit},
+and @code{undo-outer-limit}. Their values are expressed in units of
+bytes of space.
The variable @code{undo-limit} sets a soft limit: Emacs keeps undo
-data for enough commands to reach this size, and perhaps exceed it, but
-does not keep data for any earlier commands beyond that. Its default
-value is 20000. The variable @code{undo-strong-limit} sets a stricter
-limit: the command which pushes the size past this amount is itself
-forgotten. Its default value is 30000.
-
- Regardless of the values of those variables, the most recent change is
-never discarded, so there is no danger that garbage collection occurring
-right after an unintentional large change might prevent you from undoing
-it.
-
- The reason the @code{undo} command has two keys, @kbd{C-x u} and
-@kbd{C-_}, set up to run it is that it is worthy of a single-character
-key, but on some keyboards it is not obvious how to type @kbd{C-_}.
-@kbd{C-x u} is an alternative you can type straightforwardly on any
-terminal.
+data for enough commands to reach this size, and perhaps exceed it,
+but does not keep data for any earlier commands beyond that. Its
+default value is 20000. The variable @code{undo-strong-limit} sets a
+stricter limit: a previous command (not the most recent one) which
+pushes the size past this amount is itself forgotten. The default
+value of @code{undo-strong-limit} is 30000.
+
+ Regardless of the values of those variables, the most recent change
+is never discarded unless it gets bigger than @code{undo-outer-limit}
+(normally 3,000,000). At that point, Emacs discards the undo data and
+warns you about it. This is the only situation in which you cannot
+undo the last command. If this happens, you can increase the value of
+@code{undo-outer-limit} to make it even less likely to happen in the
+future. But if you didn't expect the command to create such large
+undo data, then it is probably a bug and you should report it.
+@xref{Bugs,, Reporting Bugs}.
+
+ The reason the @code{undo} command has three key bindings, @kbd{C-x
+u}, @kbd{C-_} and @kbd{C-/}, is that it is worthy of a
+single-character key, but @kbd{C-x u} is more straightforward for
+beginners to type.
@node Basic Files
@section Files
Here are special commands and techniques for putting in and taking out
blank lines.
-@c widecommands
@table @kbd
@item C-o
Insert one or more blank lines after the cursor (@code{open-line}).
You can make several blank lines by typing @kbd{C-o} several times, or
by giving it a numeric argument to tell it how many blank lines to make.
-@xref{Arguments}, for how. If you have a fill prefix, then @kbd{C-o}
+@xref{Arguments}, for how. If you have a fill prefix, the @kbd{C-o}
command inserts the fill prefix on the new line, when you use it at the
beginning of a line. @xref{Fill Prefix}.
@cindex continuation line
@cindex wrapping
@cindex line wrapping
+@cindex fringes, and continuation lines
If you add too many characters to one line without breaking it with
@key{RET}, the line grows to occupy two (or more) lines on the screen.
On graphical displays, Emacs indicates line wrapping with small bent
a line gets too long. Continuation on the screen does not do that. Use
Auto Fill mode (@pxref{Filling}) if that's what you want.
-@vindex truncate-lines
@cindex truncation
+@cindex line truncation, and fringes
As an alternative to continuation, Emacs can display long lines by
@dfn{truncation}. This means that all the characters that do not fit
-in the width of the screen or window do not appear at all. They
-remain in the buffer, temporarily invisible. On terminals, @samp{$}
-in the last column informs you that the line has been truncated on the
-display. On window systems, a small straight arrow in the fringe to
-the right of the window indicates a truncated line.
+in the width of the screen or window do not appear at all. @samp{$}
+in the last column or a small straight arrow in the fringe to the
+right of the window indicates a truncated line.
-@findex toggle-truncate-lines
- Truncation instead of continuation happens whenever horizontal
-scrolling is in use, and optionally in all side-by-side windows
-(@pxref{Windows}). You can enable or disable truncation for a
-particular buffer with the command @kbd{M-x toggle-truncate-lines}.
-
- @xref{Display Vars}, for additional variables that affect how text is
-displayed.
+ @xref{Display Custom}, for more information about line truncation,
+and other variables that affect how text is displayed.
@node Position Info
@section Cursor Position Information
Display the character code of character after point, character position of
point, and column of point (@code{what-cursor-position}).
@item M-x hl-line-mode
-Enable or disable highlighting of the current line.
+Enable or disable highlighting of the current line. @xref{Cursor
+Display}.
+@item M-x size-indication-mode
+Toggle automatic display of the size of the buffer.
+@xref{Optional Mode Line}.
@end table
@findex what-page
@cindex location of point
@cindex cursor location
@cindex point location
- There are two commands for working with line numbers. @kbd{M-x
-what-line} computes the current line number and displays it in the echo
-area. To go to a given line by number, use @kbd{M-x goto-line}; it
-prompts you for the number. These line numbers count from one at the
-beginning of the buffer.
-
- You can also see the current line number in the mode line; @xref{Mode
-Line}. If you narrow the buffer, then the line number in the mode line
-is relative to the accessible portion (@pxref{Narrowing}). By contrast,
-@code{what-line} shows both the line number relative to the narrowed
-region and the line number relative to the whole buffer.
-
- By contrast, @kbd{M-x what-page} counts pages from the beginning of
-the file, and counts lines within the page, printing both numbers.
+ @kbd{M-x what-line} computes the current line number and displays it
+in the echo area. You can also see the current line number in the
+mode line; see @ref{Mode Line}. If you narrow the buffer, then the
+line number in the mode line is relative to the accessible portion
+(@pxref{Narrowing}). By contrast, @code{what-line} shows both the
+line number relative to the narrowed region and the line number
+relative to the whole buffer.
+
+ @kbd{M-x what-page} counts pages from the beginning of the file, and
+counts lines within the page, showing both numbers in the echo area.
@xref{Pages}.
@kindex M-=
@findex count-lines-region
While on this subject, we might as well mention @kbd{M-=} (@code{count-lines-region}),
-which prints the number of lines in the region (@pxref{Mark}).
+which displays the number of lines in the region (@pxref{Mark}).
@xref{Pages}, for the command @kbd{C-x l} which counts the lines in the
current page.
@kindex C-x =
@findex what-cursor-position
- The command @kbd{C-x =} (@code{what-cursor-position}) can be used to find out
-the column that the cursor is in, and other miscellaneous information about
-point. It prints a line in the echo area that looks like this:
+ The command @kbd{C-x =} (@code{what-cursor-position}) shows what
+column the cursor is in, and other miscellaneous information about
+point and the character after it. It displays a line in the echo area
+that looks like this:
@smallexample
-Char: c (0143, 99, 0x63) point=21044 of 26883(78%) column 53
+Char: c (0143, 99, 0x63) point=21044 of 26883(78%) column 53
@end smallexample
@noindent
The four values after @samp{Char:} describe the character that follows
point, first by showing it and then by giving its character code in
-octal, decimal and hex. For a non-ASCII multibyte character, these are
+octal, decimal and hex. For a non-@acronym{ASCII} multibyte character, these are
followed by @samp{ext} and the character's representation, in hex, in
the buffer's coding system, if that coding system encodes the character
safely and with a single byte (@pxref{Coding Systems}). If the
columns from the left edge of the window.
If the buffer has been narrowed, making some of the text at the
-beginning and the end temporarily inaccessible, @kbd{C-x =} prints
+beginning and the end temporarily inaccessible, @kbd{C-x =} displays
additional text describing the currently accessible range. For example, it
might display this:
@smallexample
-Char: C (0103, 67, 0x43) point=252 of 889(28%) <231 - 599> column 0
+Char: C (0103, 67, 0x43) point=252 of 889(28%) <231 - 599> column 0
@end smallexample
@noindent
point. The output might look like this:
@smallexample
-point=26957 of 26956(100%) column 0
+point=26957 of 26956(100%) column 0
@end smallexample
- @w{@kbd{C-u C-x =}} displays additional information about a character,
-in place of the buffer coordinates and column: the character set name
-and the codes that identify the character within that character set;
-ASCII characters are identified as belonging to the @code{ASCII}
-character set. In addition, the full character encoding, even if it
-takes more than a single byte, is shown after @samp{ext}. Here's an
-example for a Latin-1 character A with a grave accent in a buffer whose
-coding system is iso-2022-7bit@footnote{On terminals that support
-Latin-1 characters, the character shown after @samp{Char:} is displayed
-as the actual glyph of A with grave accent.}:
+@cindex character set of character at point
+@cindex font of character at point
+@cindex text properties at point
+ @w{@kbd{C-u C-x =}} displays the following additional information about a
+character.
-@example
-Char: @`A (04300, 2240, 0x8c0, ext ESC , A @@) (latin-iso8859-1 64)
-@end example
+@itemize @bullet
+@item
+The character set name, and the codes that identify the character
+within that character set; @acronym{ASCII} characters are identified
+as belonging to the @code{ascii} character set.
+
+@item
+The character's syntax and categories.
+
+@item
+The character's encodings, both internally in the buffer, and externally
+if you were to save the file.
+
+@item
+What to type to input the character in the current input method
+(if it supports the character).
+
+@item
+If you are running Emacs on a window system, the font name and glyph
+code for the character. If you are running Emacs on a terminal, the
+code(s) sent to the terminal.
+
+@item
+The character's text properties (@pxref{Text Properties,,,
+elisp, the Emacs Lisp Reference Manual}), and any overlays containing it
+(@pxref{Overlays,,, elisp, the same manual}).
+@end itemize
+
+ Here's an example showing the Latin-1 character A with grave accent,
+in a buffer whose coding system is @code{iso-latin-1}, whose
+terminal coding system is @code{iso-latin-1} (so the terminal actually
+displays the character as @samp{@`A}), and which has font-lock-mode
+(@pxref{Font Lock}) enabled:
+
+@smallexample
+ character: @`A (04300, 2240, 0x8c0, U+00C0)
+ charset: latin-iso8859-1
+ (Right-Hand Part of Latin Alphabet 1@dots{}
+ code point: 64
+ syntax: w which means: word
+ category: l:Latin
+ to input: type "`A"
+buffer code: 0x81 0xC0
+ file code: ESC 2C 41 40 (encoded by coding system iso-2022-7bit)
+ display: terminal code 0xC0
+
+There are text properties here:
+ fontified t
+@end smallexample
@node Arguments
@section Numeric Arguments
@cindex numeric arguments
@cindex prefix arguments
-@cindex arguments, numeric
-@cindex arguments, prefix
+@cindex arguments to commands
In mathematics and computer usage, the word @dfn{argument} means
``data provided to a function or operation.'' You can give any Emacs
@kindex M-@t{-}
@findex digit-argument
@findex negative-argument
- If your terminal keyboard has a @key{META} key, the easiest way to
-specify a numeric argument is to type digits and/or a minus sign while
-holding down the @key{META} key. For example,
+ If your terminal keyboard has a @key{META} key (labeled @key{ALT} on
+PC keyboards), the easiest way to specify a numeric argument is to
+type digits and/or a minus sign while holding down the @key{META} key.
+For example,
+
@example
M-5 C-n
@end example
+
@noindent
would move down five lines. The characters @kbd{Meta-1}, @kbd{Meta-2},
and so on, as well as @kbd{Meta--}, do this because they are keys bound
to commands (@code{digit-argument} and @code{negative-argument}) that
-are defined to contribute to an argument for the next command. Digits
-and @kbd{-} modified with Control, or Control and Meta, also specify
-numeric arguments.
+are defined to contribute to an argument for the next command.
+@kbd{Meta--} without digits normally means @minus{}1. Digits and
+@kbd{-} modified with Control, or Control and Meta, also specify numeric
+arguments.
@kindex C-u
@findex universal-argument
A few commands treat a plain @kbd{C-u} differently from an ordinary
argument. A few others may treat an argument of just a minus sign
differently from an argument of @minus{}1. These unusual cases are
-described when they come up; they are always for reasons of convenience
-of use of the individual command.
+described when they come up; they are always for reasons of
+convenience of use of the individual command, and they are documented
+in the command's documentation string.
You can use a numeric argument to insert multiple copies of a
character. This is straightforward unless the character is a digit; for
@section Repeating a Command
@cindex repeating a command
+ Many simple commands, such as those invoked with a single key or
+with @kbd{M-x @var{command-name} @key{RET}}, can be repeated by
+invoking them with a numeric argument that serves as a repeat count
+(@pxref{Arguments}). However, if the command you want to repeat
+prompts for some input, or uses a numeric argument in another way,
+repetition using a numeric argument might be problematical.
+
@kindex C-x z
@findex repeat
The command @kbd{C-x z} (@code{repeat}) provides another way to repeat
z z z}. The first @kbd{C-x z} repeats the command once, and each
subsequent @kbd{z} repeats it once again.
+@ignore
+ arch-tag: cda8952a-c439-41c1-aecf-4bc0d6482956
+@end ignore