-@c This is part of the Emacs manual.
-@c Copyright (C) 1985, 86, 87, 93, 94, 95, 97, 2000 Free Software Foundation, Inc.
-@c See file emacs.texi for copying conditions.
-@node Basic, Minibuffer, Exiting, Top
-@chapter Basic Editing Commands
-
-@kindex C-h t
-@findex help-with-tutorial
- We now give the basics of how to enter text, make corrections, and
-save the text in a file. If this material is new to you, you might
-learn it more easily by running the Emacs learn-by-doing tutorial. To
-use the tutorial, run Emacs and type @kbd{Control-h t}
-(@code{help-with-tutorial}).
-
- To clear the screen and redisplay, type @kbd{C-l} (@code{recenter}).
-
-@menu
-
-* Inserting Text:: Inserting text by simply typing it.
-* Moving Point:: How to move the cursor to the place where you want to
- change something.
-* Erasing:: Deleting and killing text.
-* Undo:: Undoing recent changes in the text.
-* Files: Basic Files. Visiting, creating, and saving files.
-* Help: Basic Help. Asking what a character does.
-* Blank Lines:: Commands to make or delete blank lines.
-* Continuation Lines:: Lines too wide for the screen.
-* Position Info:: What page, line, row, or column is point on?
-* Arguments:: Numeric arguments for repeating a command.
-* Repeating:: A short-cut for repeating the previous command.
-@end menu
-
-@node Inserting Text
-@section Inserting Text
-
-@cindex insertion
-@cindex graphic characters
- To insert printing characters into the text you are editing, just type
-them. This inserts the characters you type into the buffer at the
-cursor (that is, at @dfn{point}; @pxref{Point}). The cursor moves
-forward, and any text after the cursor moves forward too. If the text
-in the buffer is @samp{FOOBAR}, with the cursor before the @samp{B},
-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.
-
-@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
-at the beginning of a line deletes the preceding newline, thus joining
-the line with the preceding line.
-
- Emacs can split lines automatically when they become too long, if you
-turn on a special minor mode called @dfn{Auto Fill} mode.
-@xref{Filling}, for how to use Auto Fill mode.
-
- If you prefer to have text characters replace (overwrite) existing
-text rather than shove it to the right, you can enable Overwrite mode,
-a minor mode. @xref{Minor Modes}.
-
-@cindex quoting
-@kindex C-q
-@findex quoted-insert
- Direct insertion works for printing characters and @key{SPC}, but other
-characters act as editing commands and do not insert themselves. If you
-need to insert a control character or a character whose code is above 200
-octal, you must @dfn{quote} it by typing the character @kbd{Control-q}
-(@code{quoted-insert}) first. (This character's name is normally written
-@kbd{C-q} for short.) There are two ways to use @kbd{C-q}:@refill
-
-@itemize @bullet
-@item
-@kbd{C-q} followed by any non-graphic character (even @kbd{C-g})
-inserts that character.
-
-@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.)
-@end itemize
-
-@noindent
-When multibyte characters are enabled, if you specify a code in the
-range 0200 through 0377 octal, @kbd{C-q} assumes that you intend to use
-some ISO Latin-@var{n} character set, and converts the specified code to
-the corresponding Emacs character code. @xref{Enabling Multibyte}. You
-select @emph{which} ISO Latin character set though your choice of
-language environment (@pxref{Language Environments}).
-
-@vindex read-quoted-char-radix
-To use decimal or hexadecimal instead of octal, set the variable
-@code{read-quoted-char-radix} to 10 or 16. If the radix is greater than
-10, some letters starting with @kbd{a} serve as part of a character
-code, just like digits.
-
-A numeric argument to @kbd{C-q} specifies how many copies of the
-quoted character should be inserted (@pxref{Arguments}).
-
-@findex newline
-@findex self-insert
- Customization information: @key{DEL} in most modes runs the command
-@code{delete-backward-char}; @key{RET} runs the command @code{newline}, and
-self-inserting printing characters run the command @code{self-insert},
-which inserts whatever character was typed to invoke it. Some major modes
-rebind @key{DEL} to other commands.
-
-@node Moving Point
-@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
-@cindex moving the cursor
- To do more than insert characters, you have to know how to move point
-(@pxref{Point}). The simplest way to do this is with arrow keys, or by
-clicking the left mouse button where you want to move to.
-
- There are also control and meta characters for cursor motion. Some
-are equivalent to the arrow keys (these date back to the days before
-terminals had arrow keys, and are usable on terminals which don't have
-them). Others do more sophisticated things.
-
-@kindex C-a
-@kindex C-e
-@kindex C-f
-@kindex C-b
-@kindex C-n
-@kindex C-p
-@kindex M->
-@kindex M-<
-@kindex M-r
-@findex beginning-of-line
-@findex end-of-line
-@findex forward-char
-@findex backward-char
-@findex next-line
-@findex previous-line
-@findex beginning-of-buffer
-@findex end-of-buffer
-@findex goto-char
-@findex goto-line
-@findex move-to-window-line
-@table @kbd
-@item C-a
-Move to the beginning of the line (@code{beginning-of-line}).
-@item C-e
-Move to the end of the line (@code{end-of-line}).
-@item C-f
-Move forward one character (@code{forward-char}).
-@item C-b
-Move backward one character (@code{backward-char}).
-@item M-f
-Move forward one word (@code{forward-word}).
-@item M-b
-Move backward one word (@code{backward-word}).
-@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. When on
-the last line of text, @kbd{C-n} creates a new line and moves onto it.
-@item C-p
-Move up one line, vertically (@code{previous-line}).
-@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.
-
-A numeric argument says which screen line to place point on. It counts
-screen lines down from the top of the window (zero for the top line). A
-negative argument counts lines from the bottom (@minus{}1 for the bottom
-line).
-@item M-<
-Move to the top of the buffer (@code{beginning-of-buffer}). With
-numeric argument @var{n}, move to @var{n}/10 of the way from the top.
-@xref{Arguments}, for more information on numeric arguments.@refill
-@item M->
-Move to the end of the buffer (@code{end-of-buffer}).
-@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 C-x C-n
-@findex set-goal-column
-@kindex C-x C-n
-Use the current column of point as the @dfn{semipermanent goal column} for
-@kbd{C-n} and @kbd{C-p} (@code{set-goal-column}). Henceforth, those
-commands always move to this column in each line moved into, or as
-close as possible given the contents of the line. This goal column remains
-in effect until canceled.
-@item C-u C-x C-n
-Cancel the goal column. Henceforth, @kbd{C-n} and @kbd{C-p} once
-again try to stick to a fixed horizontal position, as usual.
-@end table
-
-@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
-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
- Normally, @kbd{C-n} on the last line of a buffer appends a newline to
-it. If the variable @code{next-line-add-newlines} is @code{nil}, then
-@kbd{C-n} gets an error instead (like @kbd{C-p} on the first line).
-
-@node Erasing
-@section Erasing Text
-
-@table @kbd
-@item @key{DEL}
-Delete the character before point (@code{delete-backward-char}).
-@item C-d
-Delete the character after point (@code{delete-char}).
-@item C-k
-Kill to the end of the line (@code{kill-line}).
-@item M-d
-Kill forward to the end of the next word (@code{kill-word}).
-@item M-@key{DEL}
-Kill back to the beginning of the previous word
-(@code{backward-kill-word}).
-@end table
-
-@cindex killing characters and lines
-@cindex deleting characters and lines
-@cindex erasing characters and lines
- You already know about the @key{DEL} key which deletes the character
-before point (that is, before the cursor). Another key, @kbd{Control-d}
-(@kbd{C-d} for short), deletes the character after point (that is, the
-character that the cursor is on). This shifts the rest of the text on
-the line to the left. If you type @kbd{C-d} at the end of a line, it
-joins together that line and the next line.
-
- To erase a larger amount of text, use the @kbd{C-k} key, which kills a
-line at a time. If you type @kbd{C-k} at the beginning or middle of a
-line, it kills all the text up to the end of the line. If you type
-@kbd{C-k} at the end of a line, it joins that line and the next line.
-
- @xref{Killing}, for more flexible ways of killing text.
-
-@node Undo
-@section Undoing Changes
-@cindex undo
-@cindex changes, undoing
-
- You can undo all the recent changes in the buffer text, up to a
-certain point. Each buffer records changes individually, and the undo
-command always applies to the current buffer. Usually each editing
-command makes a separate entry in the undo records, but some commands
-such as @code{query-replace} make many entries, and very simple commands
-such as self-inserting characters are often grouped to make undoing less
-tedious.
-
-@table @kbd
-@item C-x u
-Undo one batch of changes---usually, one command worth (@code{undo}).
-@item C-_
-The same.
-@item C-u C-x u
-Undo one batch of changes in the region.
-@end table
-
-@kindex C-x u
-@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.
-
- 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.
-
- 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.
-
-@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.
-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.
-
- If you notice that a buffer has been modified accidentally, the
-easiest way to recover is to type @kbd{C-_} repeatedly until the stars
-disappear from the front of the mode line. At this time, all the
-modifications you made have been canceled. Whenever an undo command
-makes the stars disappear from the mode line, it means that the buffer
-contents are the same as they were when the file was last read in or
-saved.
-
- If you do not remember whether you changed the buffer deliberately,
-type @kbd{C-_} once. When you see the last change you made undone, you
-will see whether it was an intentional change. If it was an accident,
-leave it undone. If it was deliberate, redo the change as described
-above.
-
- Not all buffers record undo information. Buffers whose names start with
-spaces don't; these buffers are used internally by Emacs and its extensions
-to hold text that users don't normally look at or edit.
-
- You cannot undo mere cursor motion; only changes in the buffer
-contents save undo information. However, some cursor motion commands
-set the mark, so if you use these commands from time to time, you can
-move back to the neighborhoods you have moved through by popping the
-mark ring (@pxref{Mark Ring}).
-
-@vindex undo-limit
-@vindex undo-strong-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.
-
- 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.
-
-@node Basic Files
-@section Files
-
- The commands described above are sufficient for creating and altering
-text in an Emacs buffer; the more advanced Emacs commands just make
-things easier. But to keep any text permanently you must put it in a
-@dfn{file}. Files are named units of text which are stored by the
-operating system for you to retrieve later by name. To look at or use
-the contents of a file in any way, including editing the file with
-Emacs, you must specify the file name.
-
- Consider a file named @file{/usr/rms/foo.c}. In Emacs, to begin editing
-this file, type
-
-@example
-C-x C-f /usr/rms/foo.c @key{RET}
-@end example
-
-@noindent
-Here the file name is given as an @dfn{argument} to the command @kbd{C-x
-C-f} (@code{find-file}). That command uses the @dfn{minibuffer} to
-read the argument, and you type @key{RET} to terminate the argument
-(@pxref{Minibuffer}).@refill
-
- Emacs obeys the command by @dfn{visiting} the file: creating a buffer,
-copying the contents of the file into the buffer, and then displaying
-the buffer for you to edit. If you alter the text, you can @dfn{save}
-the new text in the file by typing @kbd{C-x C-s} (@code{save-buffer}).
-This makes the changes permanent by copying the altered buffer contents
-back into the file @file{/usr/rms/foo.c}. Until you save, the changes
-exist only inside Emacs, and the file @file{foo.c} is unaltered.
-
- To create a file, just visit the file with @kbd{C-x C-f} as if it
-already existed. This creates an empty buffer in which you can insert
-the text you want to put in the file. The file is actually created when
-you save this buffer with @kbd{C-x C-s}.
-
- Of course, there is a lot more to learn about using files. @xref{Files}.
-
-@node Basic Help
-@section Help
-
-@cindex getting help with keys
- If you forget what a key does, you can find out with the Help
-character, which is @kbd{C-h} (or @key{F1}, which is an alias for
-@kbd{C-h}). Type @kbd{C-h k} followed by the key you want to know
-about; for example, @kbd{C-h k C-n} tells you all about what @kbd{C-n}
-does. @kbd{C-h} is a prefix key; @kbd{C-h k} is just one of its
-subcommands (the command @code{describe-key}). The other subcommands of
-@kbd{C-h} provide different kinds of help. Type @kbd{C-h} twice to get
-a description of all the help facilities. @xref{Help}.@refill
-
-@node Blank Lines
-@section Blank Lines
-
-@cindex inserting blank lines
-@cindex deleting blank lines
- 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}).
-@item C-x C-o
-Delete all but one of many consecutive blank lines
-(@code{delete-blank-lines}).
-@end table
-
-@kindex C-o
-@kindex C-x C-o
-@cindex blank lines
-@findex open-line
-@findex delete-blank-lines
- When you want to insert a new line of text before an existing line, you
-can do it by typing the new line of text, followed by @key{RET}.
-However, it may be easier to see what you are doing if you first make a
-blank line and then insert the desired text into it. This is easy to do
-using the key @kbd{C-o} (@code{open-line}), which inserts a newline
-after point but leaves point in front of the newline. After @kbd{C-o},
-type the text for the new line. @kbd{C-o F O O} has the same effect as
-@w{@kbd{F O O @key{RET}}}, except for the final location of point.
-
- 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}
-command inserts the fill prefix on the new line, when you use it at the
-beginning of a line. @xref{Fill Prefix}.
-
- The easy way to get rid of extra blank lines is with the command
-@kbd{C-x C-o} (@code{delete-blank-lines}). @kbd{C-x C-o} in a run of
-several blank lines deletes all but one of them. @kbd{C-x C-o} on a
-solitary blank line deletes that blank line. When point is on a
-nonblank line, @kbd{C-x C-o} deletes any blank lines following that
-nonblank line.
-
-@node Continuation Lines
-@section Continuation Lines
-
-@cindex continuation line
-@cindex wrapping
-@cindex line wrapping
- If you add too many characters to one line without breaking it with
-@key{RET}, the line will grow to occupy two (or more) lines on the screen,
-with a @samp{\} at the extreme right margin of all but the last of them.
-The @samp{\} says that the following screen line is not really a distinct
-line in the text, but just the @dfn{continuation} of a line too long to fit
-the screen. Continuation is also called @dfn{line wrapping}.
-
- Sometimes it is nice to have Emacs insert newlines automatically when
-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
-@findex toggle-truncate-lines
-@cindex truncation
- 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. @samp{$} is used in the last column
-instead of @samp{\} to inform you that truncation is in effect.
-
- Truncation instead of continuation happens whenever horizontal
-scrolling is in use, and optionally in all side-by-side windows
-(@pxref{Windows}). You can enable truncation for a particular buffer by
-setting the variable @code{truncate-lines} to non-@code{nil} in that
-buffer. (@xref{Variables}.) Altering the value of
-@code{truncate-lines} makes it local to the current buffer; until that
-time, the default value is in effect. The default is initially
-@code{nil}. @xref{Locals}.
-
- The command @kbd{M-x toggle-truncate-lines} toggles the display
-between continuation and truncation.
-
- @xref{Display Vars}, for additional variables that affect how text is
-displayed.
-
-@node Position Info
-@section Cursor Position Information
-
- Here are commands to get information about the size and position of
-parts of the buffer, and to count lines.
-
-@table @kbd
-@item M-x what-page
-Print page number of point, and line number within page.
-@item M-x what-line
-Print line number of point in the buffer.
-@item M-x line-number-mode
-@itemx M-x column-number-mode
-Toggle automatic display of current line number or column number.
-@xref{Optional Mode Line}.
-@item M-=
-Print number of lines in the current region (@code{count-lines-region}).
-@xref{Mark}, for information about the region.
-@item C-x =
-Print character code of character after point, character position of
-point, and column of point (@code{what-cursor-position}).
-@item M-x hl-line-mode
-Highlighting the current line.
-@end table
-
-@findex what-page
-@findex what-line
-@cindex line number commands
-@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.
-@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}).
-@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:
-
-@smallexample
-Char: c (0143, 99, 0x63) point=21044 of 26883(78%) column 53
-@end smallexample
-
-@noindent
-(In fact, this is the output produced when point is before the
-@samp{column} in the example.)
-
- 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
-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
-character's encoding is longer than one byte, Emacs shows @samp{ext ...}.
-
- @samp{point=} is followed by the position of point expressed as a character
-count. The front of the buffer counts as position 1, one character later
-as 2, and so on. The next, larger, number is the total number of characters
-in the buffer. Afterward in parentheses comes the position expressed as a
-percentage of the total size.
-
- @samp{column} is followed by the horizontal position of point, in
-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
-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
-@end smallexample
-
-@noindent
-where the two extra numbers give the smallest and largest character
-position that point is allowed to assume. The characters between those
-two positions are the accessible ones. @xref{Narrowing}.
-
- If point is at the end of the buffer (or the end of the accessible
-part), the @w{@kbd{C-x =}} output does not describe a character after
-point. The output might look like this:
-
-@smallexample
-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.}:
-
-@example
-Char: @`A (04300, 2240, 0x8c0, ext ESC , A @@) (latin-iso8859-1 64)
-@end example
-
-@findex hl-line-mode
-@findex blink-cursor-mode
-@cindex cursor, locating visually
-@cindex cursor, blinking
-@kbd{M-x hl-line-mode} turns on a global minor mode which highlights the
-line about point in the selected window (on terminals which support
-highlighting). Some people find this convenient. If you find the
-cursor difficult to spot, you might try changing its color by
-customizing the @code{cursor} face or rely on (the default)
-@code{blink-cursor-mode}. Cursor color and blinking can be conrolled
-via the @code{cursor} Custom group.
-
-@node Arguments
-@section Numeric Arguments
-@cindex numeric arguments
-@cindex prefix arguments
-@cindex arguments, numeric
-@cindex arguments, prefix
-
- In mathematics and computer usage, the word @dfn{argument} means
-``data provided to a function or operation.'' You can give any Emacs
-command a @dfn{numeric argument} (also called a @dfn{prefix argument}).
-Some commands interpret the argument as a repetition count. For
-example, @kbd{C-f} with an argument of ten moves forward ten characters
-instead of one. With these commands, no argument is equivalent to an
-argument of one. Negative arguments tell most such commands to move or
-act in the opposite direction.
-
-@kindex M-1
-@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,
-@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.
-
-@kindex C-u
-@findex universal-argument
- Another way of specifying an argument is to use the @kbd{C-u}
-(@code{universal-argument}) command followed by the digits of the
-argument. With @kbd{C-u}, you can type the argument digits without
-holding down modifier keys; @kbd{C-u} works on all terminals. To type a
-negative argument, type a minus sign after @kbd{C-u}. Just a minus sign
-without digits normally means @minus{}1.
-
- @kbd{C-u} followed by a character which is neither a digit nor a minus
-sign has the special meaning of ``multiply by four.'' It multiplies the
-argument for the next command by four. @kbd{C-u} twice multiplies it by
-sixteen. Thus, @kbd{C-u C-u C-f} moves forward sixteen characters. This
-is a good way to move forward ``fast,'' since it moves about 1/5 of a line
-in the usual size screen. Other useful combinations are @kbd{C-u C-n},
-@kbd{C-u C-u C-n} (move down a good fraction of a screen), @kbd{C-u C-u
-C-o} (make ``a lot'' of blank lines), and @kbd{C-u C-k} (kill four
-lines).@refill
-
- Some commands care only about whether there is an argument, and not about
-its value. For example, the command @kbd{M-q} (@code{fill-paragraph}) with
-no argument fills text; with an argument, it justifies the text as well.
-(@xref{Filling}, for more information on @kbd{M-q}.) Plain @kbd{C-u} is a
-handy way of providing an argument for such commands.
-
- Some commands use the value of the argument as a repeat count, but do
-something peculiar when there is no argument. For example, the command
-@kbd{C-k} (@code{kill-line}) with argument @var{n} kills @var{n} lines,
-including their terminating newlines. But @kbd{C-k} with no argument is
-special: it kills the text up to the next newline, or, if point is right at
-the end of the line, it kills the newline itself. Thus, two @kbd{C-k}
-commands with no arguments can kill a nonblank line, just like @kbd{C-k}
-with an argument of one. (@xref{Killing}, for more information on
-@kbd{C-k}.)@refill
-
- 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.
-
- You can use a numeric argument to insert multiple copies of a
-character. This is straightforward unless the character is a digit; for
-example, @kbd{C-u 6 4 a} inserts 64 copies of the character @samp{a}.
-But this does not work for inserting digits; @kbd{C-u 6 4 1} specifies
-an argument of 641, rather than inserting anything. To separate the
-digit to insert from the argument, type another @kbd{C-u}; for example,
-@kbd{C-u 6 4 C-u 1} does insert 64 copies of the character @samp{1}.
-
- We use the term ``prefix argument'' as well as ``numeric argument'' to
-emphasize that you type the argument before the command, and to
-distinguish these arguments from minibuffer arguments that come after
-the command.
-
-@node Repeating
-@section Repeating a Command
-@cindex repeating a command
-
-@kindex C-x z
-@findex repeat
- The command @kbd{C-x z} (@code{repeat}) provides another way to repeat
-an Emacs command many times. This command repeats the previous Emacs
-command, whatever that was. Repeating a command uses the same arguments
-that were used before; it does not read new arguments each time.
-
- To repeat the command more than once, type additional @kbd{z}'s: each
-@kbd{z} repeats the command one more time. Repetition ends when you
-type a character other than @kbd{z}, or press a mouse button.
-
- For example, suppose you type @kbd{C-u 2 0 C-d} to delete 20
-characters. You can repeat that command (including its argument) three
-additional times, to delete a total of 80 characters, by typing @kbd{C-x
-z z z}. The first @kbd{C-x z} repeats the command once, and each
-subsequent @kbd{z} repeats it once again.
-
+@c This is part of the Emacs manual.
+@c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 2000, 2001,
+@c 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+@c See file emacs.texi for copying conditions.
+@node Basic, Minibuffer, Exiting, Top
+@chapter Basic Editing Commands
+
+@kindex C-h t
+@findex help-with-tutorial
+ Here we explain the basics of how to enter text, make corrections,
+and save the text in a file. If this material is new to you, we
+suggest you first run the Emacs learn-by-doing tutorial, by typing
+@kbd{Control-h t} inside Emacs. (@code{help-with-tutorial}).
+
+ To clear and redisplay the screen, type @kbd{C-l} (@code{recenter}).
+
+@menu
+
+* Inserting Text:: Inserting text by simply typing it.
+* Moving Point:: Moving the cursor to the place where you want to
+ change something.
+* Erasing:: Deleting and killing text.
+* Basic Undo:: Undoing recent changes in the text.
+* Files: Basic Files. Visiting, creating, and saving files.
+* Help: Basic Help. Asking what a character does.
+* Blank Lines:: Making and deleting blank lines.
+* Continuation Lines:: How Emacs displays lines too wide for the screen.
+* Position Info:: What page, line, row, or column is point on?
+* Arguments:: Numeric arguments for repeating a command N times.
+* Repeating:: Repeating the previous command quickly.
+@end menu
+
+@node Inserting Text
+@section Inserting Text
+
+@cindex insertion
+@cindex graphic characters
+ Typing printing characters inserts them into the text you are
+editing. It inserts them into the buffer at the cursor; more
+precisely, it inserts them at @dfn{point}, but the cursor normally
+shows where point is. @xref{Point}.
+
+ Insertion moves the cursor forward, and the following text moves
+forward with the cursor. If the text in the buffer is @samp{FOOBAR},
+with the cursor before the @samp{B}, and 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 the large key
+labeled @key{DEL}, @key{BACKSPACE} or @key{DELETE} which is a short
+distance above the @key{RET} or @key{ENTER} key. Regardless of the
+label on that key, Emacs thinks of it as @key{DEL}, and that's what we
+call it in this manual. @key{DEL} is the key you normally use outside
+Emacs to erase the last character that you typed.
+
+ 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 sets up @key{DEL} automatically. In some
+cases, especially with text-only terminals, Emacs may guess wrong. If
+the key that ought to erase the last character doesn't do it in Emacs,
+see @ref{DEL Does Not Delete}.
+
+ Most PC keyboards have both a @key{BACKSPACE} key a little ways
+above @key{RET} or @key{ENTER}, and a @key{DELETE} key elsewhere. On
+these keyboards, Emacs tries to set up @key{BACKSPACE} as @key{DEL}.
+The @key{DELETE} key deletes ``forwards'' like @kbd{C-d} (see below),
+which means it deletes the character underneath the cursor (after
+point).
+
+@kindex RET
+@cindex newline
+ To end a line and start typing a new one, type @key{RET}. (This
+key may be labeled @key{RETURN} or @key{ENTER}, but in Emacs we call
+it @key{RET}.) This inserts a newline character in the buffer. If
+point is at the end of the line, this creates a new blank line after
+it. If point is in the middle of a line, the effect is to split that
+line. Typing @key{DEL} when the cursor is at the beginning of a line
+deletes the preceding newline character, thus joining the line with
+the one before it.
+
+ Emacs can split lines automatically when they become too long, if
+you turn on a special minor mode called @dfn{Auto Fill} mode.
+@xref{Filling}, for Auto Fill mode and other methods of @dfn{filling}
+text.
+
+ If you prefer printing characters to replace (overwrite) existing
+text, rather than shove it to the right, you should enable Overwrite
+mode, a minor mode. @xref{Minor Modes}.
+
+@cindex quoting
+@kindex C-q
+@findex quoted-insert
+ Only printing characters and @key{SPC} insert themselves in Emacs.
+Other characters act as editing commands and do not insert themselves.
+These include control characters, and characters with codes above 200
+octal. If you need to insert one of these characters in the buffer,
+you must @dfn{quote} it by typing the character @kbd{Control-q}
+(@code{quoted-insert}) first. (This character's name is normally
+written @kbd{C-q} for short.) There are two ways to use
+@kbd{C-q}:
+
+@itemize @bullet
+@item
+@kbd{C-q} followed by any non-graphic character (even @kbd{C-g})
+inserts that character.
+
+@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 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
+@noindent
+When multibyte characters are enabled, if you specify a code in the
+range 0200 through 0377 octal, @kbd{C-q} assumes that you intend to
+use some ISO 8859-@var{n} character set, and converts the specified
+code to the corresponding Emacs character code. @xref{Enabling
+Multibyte}. You select @emph{which} of the ISO 8859 character sets to
+use through your choice of language environment (@pxref{Language
+Environments}).
+
+@vindex read-quoted-char-radix
+To use decimal or hexadecimal instead of octal, set the variable
+@code{read-quoted-char-radix} to 10 or 16. If the radix is greater than
+10, some letters starting with @kbd{a} serve as part of a character
+code, just like digits.
+
+A numeric argument tells @kbd{C-q} how many copies of the quoted
+character to insert (@pxref{Arguments}).
+
+@findex newline
+@findex self-insert
+ Customization information: @key{DEL} in most modes runs the command
+@code{delete-backward-char}; @key{RET} runs the command
+@code{newline}, and self-inserting printing characters run the command
+@code{self-insert}, which inserts whatever character you typed. Some
+major modes rebind @key{DEL} to other commands.
+
+@node Moving Point
+@section Changing the Location of Point
+
+@cindex arrow keys
+@cindex moving point
+@cindex movement
+@cindex cursor motion
+@cindex moving the cursor
+ To do more than insert characters, you have to know how to move point
+(@pxref{Point}). The simplest way to do this is with arrow keys, or by
+clicking the left mouse button where you want to move to.
+
+ There are also control and meta characters for cursor motion. Some
+are equivalent to the arrow keys (it is faster to use these control
+keys than move your hand over to the arrow keys). Others do more
+sophisticated things.
+
+@kindex C-a
+@kindex C-e
+@kindex C-f
+@kindex C-b
+@kindex C-n
+@kindex C-p
+@kindex M->
+@kindex M-<
+@kindex M-r
+@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 previous-line
+@findex beginning-of-buffer
+@findex end-of-buffer
+@findex goto-char
+@findex goto-line
+@findex move-to-window-line
+@table @kbd
+@item C-a
+Move to the beginning of the line (@code{move-beginning-of-line}).
+@item C-e
+Move to the end of the line (@code{move-end-of-line}).
+@item C-f
+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}). The left-arrow
+key has the same effect.
+@item M-f
+Move forward one word (@code{forward-word}).
+@item M-b
+Move backward one word (@code{backward-word}).
+@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 move to the middle of the next. The
+down-arrow key does the same thing.
+@item C-p
+Move up one line, vertically (@code{previous-line}). The up-arrow key
+has the same effect. This command preserves position within the line,
+like @kbd{C-n}.
+@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.
+A numeric argument says which screen line to place point on, counting
+downward from the top of the window (zero means the top line). A
+negative argument counts lines up from the bottom (@minus{}1 means the
+bottom line).
+@item M-<
+Move to the top of the buffer (@code{beginning-of-buffer}). With
+numeric argument @var{n}, move to @var{n}/10 of the way from the top.
+@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 described further 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-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 in the buffer, and you type @key{RET} with the
+minibuffer empty, that number is used for @var{n}.
+@item C-x C-n
+@findex set-goal-column
+@kindex C-x C-n
+Use the current column of point as the @dfn{semipermanent goal column}
+for @kbd{C-n} and @kbd{C-p} (@code{set-goal-column}). When a
+semipermanent goal column is in effect, those commands always try to
+move to this column, or as close as possible to it, after moving
+vertically. The goal column remains in effect until canceled.
+@item C-u C-x C-n
+Cancel the goal column. Henceforth, @kbd{C-n} and @kbd{C-p} try to
+preserve the horizontal position, as usual.
+@end table
+
+@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 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 stops at the end of the buffer when you use it on
+the last line of the buffer. However, 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 into it.
+
+@node Erasing
+@section Erasing Text
+
+@table @kbd
+@item @key{DEL}
+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---it is @key{DEL}.
+If @key{BACKSPACE} is @key{DEL}, 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
+Kill forward to the end of the next word (@code{kill-word}).
+@item M-@key{DEL}
+Kill back to the beginning of the previous word
+(@code{backward-kill-word}).
+@end table
+
+@cindex killing characters and lines
+@cindex deleting characters and lines
+@cindex erasing characters and lines
+ You already know about the @key{DEL} key which deletes the character
+before point (that is, before the cursor). Another key, @kbd{Control-d}
+(@kbd{C-d} for short), deletes the character after point (that is, the
+character that the cursor is on). This shifts the rest of the text on
+the line to the left. If you type @kbd{C-d} at the end of a line, it
+joins that line with the following line.
+
+ To erase a larger amount of text, use the @kbd{C-k} key, which
+erases (kills) a line at a time. If you type @kbd{C-k} at the
+beginning or middle of a line, it kills all the text up to the end of
+the line. If you type @kbd{C-k} at the end of a line, it joins that
+line with the following line.
+
+ @xref{Killing}, for more flexible ways of killing text.
+
+@node Basic Undo
+@section Undoing Changes
+
+ Emacs records a list of changes made in the buffer text, so you can
+you can undo recent changes, as far as the records go.
+Usually each editing command makes a separate entry in the undo
+records, but sometimes an entry covers just part of a command, and
+very simple commands may be grouped.
+
+@table @kbd
+@item C-x u
+Undo one entry of the undo records---usually, one command worth
+(@code{undo}).
+@item C-_
+@itemx C-/
+The same.
+@end table
+
+ The command @kbd{C-x u} (or @kbd{C-_} or @kbd{C-/}) is how you undo.
+Normally this command undoes the last change, and moves point back to
+where it was before the change.
+
+ If you repeat @kbd{C-x u} (or its aliases), each repetition undoes
+another, earlier change, back to the limit of the undo information
+available. If all recorded changes have already been undone, the undo
+command displays an error message and does nothing.
+
+ The undo command applies only to changes in the buffer; you can't
+use it to undo mere cursor motion. However, some cursor motion
+commands set the mark, so if you use these commands from time to time,
+you can move back to the neighborhoods you have moved through by
+popping the mark ring (@pxref{Mark Ring}).
+
+@node Basic Files
+@section Files
+
+ Text that you insert in an Emacs buffer lasts only as long as the
+Emacs session. To keep any text permanently you must put it in a
+@dfn{file}. Files are named units of text which are stored by the
+operating system for you to retrieve later by name. To use the
+contents of a file in any way, you must specify the file name. That
+includes editing the file with Emacs.
+
+ Suppose there is a file named @file{test.emacs} in your home
+directory. To begin editing this file in Emacs, type
+
+@example
+C-x C-f test.emacs @key{RET}
+@end example
+
+@noindent
+Here the file name is given as an @dfn{argument} to the command @kbd{C-x
+C-f} (@code{find-file}). That command uses the @dfn{minibuffer} to
+read the argument, and you type @key{RET} to terminate the argument
+(@pxref{Minibuffer}).
+
+ Emacs obeys this command by @dfn{visiting} the file: it creates a
+buffer, it copies the contents of the file into the buffer, and then
+displays the buffer for editing. If you alter the text, you can
+@dfn{save} the new text in the file by typing @kbd{C-x C-s}
+(@code{save-buffer}). This copies the altered buffer contents back
+into the file @file{test.emacs}, making them permanent. Until you
+save, the changed text exists only inside Emacs, and the file
+@file{test.emacs} is unaltered.
+
+ To create a file, just visit it with @kbd{C-x C-f} as if it already
+existed. This creates an empty buffer, in which you can insert the
+text you want to put in the file. Emacs actually creates the file the
+first time you save this buffer with @kbd{C-x C-s}.
+
+ To learn more about using files in Emacs, see @ref{Files}.
+
+@node Basic Help
+@section Help
+
+@cindex getting help with keys
+ If you forget what a key does, you can find out with the Help
+character, which is @kbd{C-h} (or @key{F1}, which is an alias for
+@kbd{C-h}). Type @kbd{C-h k} followed by the key of interest; for
+example, @kbd{C-h k C-n} tells you what @kbd{C-n} does. @kbd{C-h} is
+a prefix key; @kbd{C-h k} is just one of its subcommands (the command
+@code{describe-key}). The other subcommands of @kbd{C-h} provide
+different kinds of help. Type @kbd{C-h} twice to get a description of
+all the help facilities. @xref{Help}.
+
+@node Blank Lines
+@section Blank Lines
+
+@cindex inserting blank lines
+@cindex deleting blank lines
+ Here are special commands and techniques for inserting and deleting
+blank lines.
+
+@table @kbd
+@item C-o
+Insert one or more blank lines after the cursor (@code{open-line}).
+@item C-x C-o
+Delete all but one of many consecutive blank lines
+(@code{delete-blank-lines}).
+@end table
+
+@kindex C-o
+@kindex C-x C-o
+@cindex blank lines
+@findex open-line
+@findex delete-blank-lines
+ To insert a new line of text before an existing line,
+type the new line of text, followed by @key{RET}.
+However, it may be easier to see what you are doing if you first make a
+blank line and then insert the desired text into it. This is easy to do
+using the key @kbd{C-o} (@code{open-line}), which inserts a newline
+after point but leaves point in front of the newline. After @kbd{C-o},
+type the text for the new line. @kbd{C-o F O O} has the same effect as
+@w{@kbd{F O O @key{RET}}}, except for the final location of point.
+
+ You can make several blank lines by typing @kbd{C-o} several times, or
+by giving it a numeric argument specifying how many blank lines to make.
+@xref{Arguments}, for how. If you have a fill prefix, the @kbd{C-o}
+command inserts the fill prefix on the new line, if typed at the
+beginning of a line. @xref{Fill Prefix}.
+
+ The easy way to get rid of extra blank lines is with the command
+@kbd{C-x C-o} (@code{delete-blank-lines}). @kbd{C-x C-o} in a run of
+several blank lines deletes all but one of them. @kbd{C-x C-o} on a
+lone blank line deletes that one. When point is on a nonblank line,
+@kbd{C-x C-o} deletes all following blank lines (if any).
+
+@node Continuation Lines
+@section Continuation Lines
+
+@cindex continuation line
+@cindex wrapping
+@cindex line wrapping
+@cindex fringes, and continuation lines
+ When a text line is too long to fit in one screen line, Emacs
+displays it on two or more screen lines. This is called
+@dfn{continuation} or @dfn{line wrapping}. On graphical displays,
+Emacs indicates line wrapping with small bent arrows in the left and
+right window fringes. On text-only terminals, Emacs displays a
+@samp{\} character at the right margin of a screen line if it is not
+the last in its text line. This @samp{\} character says that the
+following screen line is not really a new text line.
+
+ When line wrapping occurs just before a character that is wider than one
+column, some columns at the end of the previous screen line may be
+``empty.'' In this case, Emacs displays additional @samp{\}
+characters in the ``empty'' columns before the @samp{\}
+character that indicates continuation.
+
+ Continued lines can be difficult to read, since lines can break in
+the middle of a word. If you prefer, you can make Emacs insert a
+newline automatically when a line gets too long, by using Auto Fill
+mode. Or enable Long Lines mode, which ensures that wrapping only
+occurs between words. @xref{Filling}.
+
+@cindex truncation
+@cindex line truncation, and fringes
+ Emacs can optionally @dfn{truncate} long lines---this means
+displaying just one screen line worth, and the rest of the long line
+does not appear at all. @samp{$} in the last column or a small
+straight arrow in the window's right fringe indicates a truncated
+line.
+
+ @xref{Display Custom}, for more about line truncation,
+and other variables that control how text is displayed.
+
+@node Position Info
+@section Cursor Position Information
+
+ Here are commands to get information about the size and position of
+parts of the buffer, and to count lines.
+
+@table @kbd
+@item M-x what-page
+Display the page number of point, and the line number within that page.
+@item M-x what-line
+Display the line number of point in the whole buffer.
+@item M-x line-number-mode
+@itemx M-x column-number-mode
+Toggle automatic display of the current line number or column number.
+@xref{Optional Mode Line}.
+@item M-=
+Display the number of lines in the current region (@code{count-lines-region}).
+@xref{Mark}, for information about the region.
+@item C-x =
+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. @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
+@findex what-line
+@cindex line number commands
+@cindex location of point
+@cindex cursor location
+@cindex point location
+ @kbd{M-x what-line} displays the current line number
+in the echo area. You can also see the current line number in the
+mode line; see @ref{Mode Line}; but if you narrow the buffer, 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
+ Use @kbd{M-=} (@code{count-lines-region}) to 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}) shows what
+cursor's column position, and other information about point and the
+character after it. It displays a line in the echo area that looks
+like this:
+
+@smallexample
+Char: c (99, #o143, #x63) point=28062 of 36168 (78%) column=53
+@end smallexample
+
+ The four values after @samp{Char:} describe the character that follows
+point, first by showing it and then by giving its character code in
+decimal, octal and hex. For a non-@acronym{ASCII} multibyte character, these are
+followed by @samp{file} 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
+character's encoding is longer than one byte, Emacs shows @samp{file ...}.
+
+ However, if the character displayed is in the range 0200 through
+0377 octal, it may actually stand for an invalid UTF-8 byte read from
+a file. In Emacs, that byte is represented as a sequence of 8-bit
+characters, but all of them together display as the original invalid
+byte, in octal code. In this case, @kbd{C-x =} shows @samp{part of
+display ...} instead of @samp{file}.
+
+ @samp{point=} is followed by the position of point expressed as a
+character count. The start of the buffer is position 1, one character
+later is position 2, and so on. The next, larger, number is the total
+number of characters in the buffer. Afterward in parentheses comes
+the position expressed as a percentage of the total size.
+
+ @samp{column=} is followed by the horizontal position of point, in
+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 =} displays
+additional text describing the currently accessible range. For example, it
+might display this:
+
+@smallexample
+Char: C (67, #o103, #x43) point=252 of 889 (28%) <231-599> column=0
+@end smallexample
+
+@noindent
+where the two extra numbers give the smallest and largest character
+position that point is allowed to assume. The characters between those
+two positions are the accessible ones. @xref{Narrowing}.
+
+ If point is at the end of the buffer (or the end of the accessible
+part), the @w{@kbd{C-x =}} output does not describe a character after
+point. The output might look like this:
+
+@smallexample
+point=36169 of 36168 (EOB) column=0
+@end smallexample
+
+@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.
+
+@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 keys to type to input the character in the current input method
+(if it supports the character).
+
+@item
+If you are running Emacs on a graphical display, the font name and
+glyph code for the character. If you are running Emacs on a text-only
+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 (2240, #o4300, #x8c0, U+00C0)
+ charset: latin-iso8859-1
+ (Right-Hand Part of Latin Alphabet 1@dots{}
+ code point: #x40
+ syntax: w which means: word
+ category: l:Latin
+ to input: type "`A" with latin-1-prefix
+buffer code: #x81 #xC0
+ file code: #xC0 (encoded by coding system iso-latin-1)
+ display: terminal code #xC0
+
+There are text properties here:
+ fontified t
+@end smallexample
+
+@node Arguments
+@section Numeric Arguments
+@cindex numeric arguments
+@cindex prefix arguments
+@cindex arguments to commands
+
+ In mathematics and computer usage, @dfn{argument} means
+``data provided to a function or operation.'' You can give any Emacs
+command a @dfn{numeric argument} (also called a @dfn{prefix argument}).
+Some commands interpret the argument as a repetition count. For
+example, @kbd{C-f} with an argument of ten moves forward ten characters
+instead of one. With these commands, no argument is equivalent to an
+argument of one. Negative arguments tell most such commands to move or
+act in the opposite direction.
+
+@kindex M-1
+@kindex M-@t{-}
+@findex digit-argument
+@findex negative-argument
+ 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
+moves 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 set up 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
+ You can also specify a numeric argument by typing @kbd{C-u}
+(@code{universal-argument}) followed by the digits. The advantage of
+@kbd{C-u} is that you can type the digits without modifier keys; thus,
+@kbd{C-u} works on all terminals. For a negative argument, type a
+minus sign after @kbd{C-u}. A minus sign without digits normally
+means @minus{}1.
+
+ @kbd{C-u} alone has the special meaning of
+``four times'': it multiplies the argument for the next command by
+four. @kbd{C-u C-u} multiplies it by sixteen. Thus, @kbd{C-u C-u
+C-f} moves forward sixteen characters. This is a good way to move
+forward ``fast,'' since it moves about 1/5 of a line in the usual size
+screen. Other useful combinations are @kbd{C-u C-n}, @kbd{C-u C-u
+C-n} (move down a good fraction of a screen), @kbd{C-u C-u C-o} (make
+``a lot'' of blank lines), and @kbd{C-u C-k} (kill four lines).
+
+ Some commands care whether there is an argument, but ignore its
+value. For example, the command @kbd{M-q} (@code{fill-paragraph})
+fills text; with an argument, it justifies the text as well.
+(@xref{Filling}, for more information on @kbd{M-q}.) Plain @kbd{C-u}
+is a handy way of providing an argument for such commands.
+
+ Some commands use the value of the argument as a repeat count, but do
+something peculiar when there is no argument. For example, the command
+@kbd{C-k} (@code{kill-line}) with argument @var{n} kills @var{n} lines,
+including their terminating newlines. But @kbd{C-k} with no argument is
+special: it kills the text up to the next newline, or, if point is right at
+the end of the line, it kills the newline itself. Thus, two @kbd{C-k}
+commands with no arguments can kill a nonblank line, just like @kbd{C-k}
+with an argument of one. (@xref{Killing}, for more information on
+@kbd{C-k}.)
+
+ 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 exist to make an individual command
+more convenient, and they are documented in that command's
+documentation string.
+
+ You can use a numeric argument before a self-inserting character to
+insert multiple copies of it. This is straightforward when the
+character is not a digit; for example, @kbd{C-u 6 4 a} inserts 64
+copies of the character @samp{a}. But this does not work for
+inserting digits; @kbd{C-u 6 4 1} specifies an argument of 641. You
+can separate the argument from the digit to insert with another
+@kbd{C-u}; for example, @kbd{C-u 6 4 C-u 1} does insert 64 copies of
+the character @samp{1}.
+
+ We use the term ``prefix argument'' as well as ``numeric argument'',
+to emphasize that you type these argument before the command, and to
+distinguish them from minibuffer arguments that come after the
+command.
+
+@node Repeating
+@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 input, or uses a numeric argument in another way, that
+method won't work.
+
+@kindex C-x z
+@findex repeat
+ The command @kbd{C-x z} (@code{repeat}) provides another way to repeat
+an Emacs command many times. This command repeats the previous Emacs
+command, whatever that was. Repeating a command uses the same arguments
+that were used before; it does not read new arguments each time.
+
+ To repeat the command more than once, type additional @kbd{z}'s: each
+@kbd{z} repeats the command one more time. Repetition ends when you
+type a character other than @kbd{z}, or press a mouse button.
+
+ For example, suppose you type @kbd{C-u 2 0 C-d} to delete 20
+characters. You can repeat that command (including its argument) three
+additional times, to delete a total of 80 characters, by typing @kbd{C-x
+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
HCoop / bpt / emacs.git / blobdiff