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date Mon, 13 Aug 2007 08:45:50 +0200
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+
+@node Basic, Undo, Command Switches, 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
+do this, type @kbd{Control-h t} (@code{help-with-tutorial}).
+
+@section Inserting Text
+
+@cindex insertion
+@cindex point
+@cindex cursor
+@cindex graphic characters
+  To insert printing characters into the text you are editing, just type
+them.  This inserts the characters into the buffer at the cursor (that
+is, at @dfn{point}; @pxref{Point}).  The cursor moves forward.  Any
+characters after the cursor move forward too.  If the text in the buffer
+is @samp{FOOBAR}, with the cursor before the @samp{B}, and you type
+@kbd{XX}, the result is @samp{FOOXXBAR}, with the cursor still before the
+@samp{B}.
+
+@kindex DEL
+@cindex deletion
+   To @dfn{delete} text you have just inserted, use @key{DEL}.
+@key{DEL} deletes the character @var{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 rubs out the newline before the line, thus
+joining the line with the preceding line.
+
+  Emacs automatically splits lines when they become too long, if you
+turn on a special mode called @dfn{Auto Fill} mode.  @xref{Filling}, for
+information on using Auto Fill mode.
+
+@findex delete-backward-char
+@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.
+
+@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.  There are two ways to use
+@kbd{C-q}:@refill
+
+@itemize @bullet
+@item
+@kbd{Control-q} followed by any non-graphic character (even @kbd{C-g})
+inserts that character.
+@item
+@kbd{Control-q} followed by three octal digits inserts the character
+with the specified character code.
+@end itemize
+
+@noindent
+A numeric argument to @kbd{C-q} specifies how many copies of the quoted
+character should be inserted (@pxref{Arguments}).
+
+  If you prefer to have text characters replace (overwrite) existing
+text instead of moving it to the right, you can enable Overwrite mode, a
+minor mode.  @xref{Minor Modes}.
+
+@section Changing the Location of Point
+
+  To do more than insert characters, you have to know how to move point
+(@pxref{Point}).  Here are a few of the available commands.
+
+  NOTE: Many of the following commands have two versions, one that uses
+the function keys (e.g. @key{LEFT} or @key{END}) and one that doesn't.
+The former versions may only be available on X terminals (i.e. not on
+TTY's), but the latter are available on all terminals.
+
+@kindex C-a
+@kindex C-e
+@kindex C-f
+@kindex C-b
+@kindex C-n
+@kindex C-p
+@kindex C-l
+@kindex C-t
+@kindex C-v
+@kindex M-v
+@kindex M->
+@kindex M-<
+@kindex M-r
+@kindex LEFT
+@kindex RIGHT
+@kindex UP
+@kindex DOWN
+@kindex HOME
+@kindex END
+@kindex PGUP
+@kindex PGDN
+@kindex C-LEFT
+@kindex C-RIGHT
+@kindex C-HOME
+@kindex C-END
+@findex beginning-of-line
+@findex end-of-line
+@findex forward-char
+@findex backward-char
+@findex next-line
+@findex previous-line
+@findex recenter
+@findex transpose-chars
+@findex beginning-of-buffer
+@findex end-of-buffer
+@findex goto-char
+@findex goto-line
+@findex move-to-window-line
+@table @kbd
+@item C-a
+@itemx HOME
+Move to the beginning of the line (@code{beginning-of-line}).
+@item C-e
+@itemx END
+Move to the end of the line (@code{end-of-line}).
+@item C-f
+@itemx RIGHT
+Move forward one character (@code{forward-char}).
+@item C-b
+@itemx LEFT
+Move backward one character (@code{backward-char}).
+@item M-f
+@itemx C-RIGHT
+Move forward one word (@code{forward-word}).
+@item M-b
+@itemx C-LEFT
+Move backward one word (@code{backward-word}).
+@item C-n
+@itemx DOWN
+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
+@itemx UP
+Move up one line, vertically (@code{previous-line}).
+@item C-v
+@itemx PGDN
+Move down one page, vertically (@code{scroll-up}).
+@item M-v
+@itemx PGUP
+Move up one page, vertically (@code{scroll-down}).
+@item C-l
+Clear the frame and reprint everything (@code{recenter}).  Text moves
+on the frame to bring point to the center of the window.
+@item M-r
+Move point to left margin on the line halfway down the frame or
+window (@code{move-to-window-line}).  Text does not move on the
+frame.  A numeric argument says how many screen lines down from the
+top of the window (zero for the top).  A negative argument counts from
+the bottom (@minus{}1 for the bottom).
+@item C-t
+Transpose two characters, the ones before and after the cursor
+@*(@code{transpose-chars}).
+@item M-<
+@itemx C-HOME
+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->
+@itemx C-END
+Move to the end of the buffer (@code{end-of-buffer}).
+@item M-x goto-char
+Read a number @var{n} and move the cursor to character number @var{n}.
+Position 1 is the beginning of the buffer.
+@item M-g
+Read a number @var{n} and move cursor to line number @var{n}
+(@code{goto-line}).  Line 1 is the beginning of the buffer.
+@item C-x C-n
+@findex set-goal-column
+Use the current column of point as the @dfn{semi-permanent 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 avoid changing the horizontal position, as usual.
+@end table
+
+@vindex track-eol
+  If you set the variable @code{track-eol} to a non-@code{nil} value,
+@kbd{C-n} and @kbd{C-p} move to the end of the line when at the end of
+the starting line.  By default, @code{track-eol} is @code{nil}.
+
+@section Erasing Text
+
+@table @kbd
+@item @key{DEL}
+Delete the character before the cursor (@code{delete-backward-char}).
+@item C-d
+Delete the character after the cursor (@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
+
+  In contrast to the @key{DEL} key, which deletes the character before
+the cursor, @kbd{Control-d} deletes the character after the cursor,
+causing the rest of the text on the line to shift left.  If
+@kbd{Control-d} is typed at the end of a line, that line and the next
+line are joined.
+
+  To erase a larger amount of text, use @kbd{Control-k}, which kills a
+line at a time.  If you use @kbd{C-k} at the beginning or in the middle
+of a line, it kills all the text up to the end of the line.  If you use
+@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.
+
+@section Files
+
+@cindex files
+  The commands above are sufficient for creating and altering text in an
+Emacs buffer.  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 and which
+you can retrieve 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}.  To begin editing
+this file from Emacs, type:
+
+@example
+C-x C-f /usr/rms/foo.c @key{RET}
+@end example
+
+@noindent
+The file name is given as an @dfn{argument} to the command @kbd{C-x
+C-f} (@code{find-file}).  The command uses the @dfn{minibuffer} to
+read the argument.  You have to type @key{RET} to terminate the argument
+(@pxref{Minibuffer}).@refill
+
+  You can also use the @b{Open...} menu item from the @b{File} menu, then
+type the name of the file to the prompt.
+
+  Emacs obeys the command by @dfn{visiting} the file: it creates a
+buffer, copies the contents of the file into the buffer, and then
+displays the buffer for you to edit.  You can make changes in the
+buffer, and then @dfn{save} the file by typing @kbd{C-x C-s}
+(@code{save-buffer}) or choosing @b{Save Buffer} from the @b{File} menu.
+This makes the changes permanent by copying the altered contents of the
+buffer back into the file @file{/usr/rms/foo.c}.  Until then, the
+changes are only inside your Emacs buffer, and the file @file{foo.c} is
+not changed.@refill
+
+  To create a file, visit the file with @kbd{C-x C-f} as if it already
+existed or choose @b{Open...} from the @b{File} menu and provide the
+name for the new file in the minibuffer.  Emacs will create an empty
+buffer in which you can insert the text you want to put in the file.
+When you save the buffer with @kbd{C-x C-s}, or by choosing @b{Save
+Buffer} from the @b{File} menu, the file is created.
+
+  To learn more about using files, @pxref{Files}.
+
+@section Help
+
+  If you forget what a key does, you can use the Help character
+(@kbd{C-h}) to find out: Type @kbd{C-h k} followed by the key you want
+to know about.  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} three times
+to get a description of all the help facilities.  @xref{Help}.@refill
+
+@menu
+* Blank Lines::        Commands to make or delete blank lines.
+* Continuation Lines:: Lines too wide for the frame.
+* Position Info::      What page, line, row, or column is point on?
+* Arguments::	       Numeric arguments for repeating a command.
+@end menu
+
+@node Blank Lines, Continuation Lines, Basic, Basic
+@section Blank Lines
+
+  Here are special commands and techniques for entering and removing
+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 just type the new line of text, followed by @key{RET}.  If you
+prefer to create a blank line first and then insert the desired text,
+use the key @kbd{C-o} (@code{open-line}), which inserts a newline after
+point but leaves point in front of the newline.  Then type
+the text into the new line.  @kbd{C-o F O O} has the same effect as
+@kbd{F O O @key{RET}}, except for the final location of point.
+
+  To create several blank lines, type @kbd{C-o} several times, or
+give @kbd{C-o} an argument indicating how many blank lines to create.
+@xref{Arguments}, for more information.
+
+  If you have many blank lines in a row and want to get rid of them, use
+@kbd{C-x C-o} (@code{delete-blank-lines}).  If point is on a blank
+line which is adjacent to at least one other blank line, @kbd{C-x C-o}
+deletes all but one of the blank lines.
+If point is on a blank line with no other adjacent blank line, the
+sole blank line is deleted.  If point is on a non-blank
+line, @kbd{C-x C-o} deletes any blank lines following that non-blank
+line.
+
+@node Continuation Lines, Position Info, Blank Lines, Basic
+@section Continuation Lines
+
+@cindex continuation line
+  If you add too many characters to one line without breaking with a
+@key{RET}, the line grows to occupy two (or more) screen lines, with a
+curved arrow at the extreme right margin of all but the last line.  The
+curved arrow indicates 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 frame.  You can use Auto Fill mode (@pxref{Filling})
+to have Emacs insert newlines automatically when a line gets too long.
+
+
+@vindex truncate-lines
+@cindex truncation
+  Instead of continuation, long lines can be displayed by @dfn{truncation}.
+This means that all the characters that do not fit in the width of the
+frame or window do not appear at all.  They remain in the buffer,
+temporarily invisible.  Three diagonal dots in the last column (instead of
+the curved arrow inform you that truncation is in effect.
+
+  To turn off continuation for a particular buffer, set the
+variable @code{truncate-lines} to non-@code{nil} in that buffer.
+Truncation instead of continuation also happens whenever horizontal
+scrolling is in use, and optionally whenever side-by-side windows are in
+use (@pxref{Windows}).  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}.@refill
+
+@node Position Info, Arguments, Continuation Lines, Basic
+@section Cursor Position Information
+
+  If you are accustomed to other display editors, you may be surprised
+that Emacs does not always display the page number or line number of
+point in the mode line.  In Emacs, this information is only rarely
+needed, and a number of commands are available to compute and print it.
+Since text is stored in a way that makes it difficult to compute the
+information, it is not displayed all the time.
+
+@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-=
+Print number of lines and characters in the current region 
+(@code{count-lines-region}).
+@item C-x =
+Print character code of character after point, character position of
+point, and column of point (@code{what-cursor-position}).
+@end table
+
+@findex what-page
+@findex what-line
+@cindex line number
+@cindex page number
+@kindex M-=
+@findex count-lines-region
+
+  There are several commands for printing line numbers:
+@itemize @bullet
+@item
+@kbd{M-x what-line} counts lines from the beginning of the file and
+prints the line number point is on.  The first line of the file is line
+number 1.  You can use these numbers as arguments to @kbd{M-x
+goto-line}.
+@item
+@kbd{M-x what-page} counts pages from the beginning of the file, and
+counts lines within the page, printing both of them.  @xref{Pages}, for
+the command @kbd{C-x l}, which counts the lines in the current page.
+@item
+@kbd{M-=} (@code{count-lines-region}) prints the number of lines in
+the region (@pxref{Mark}).
+@end itemize
+
+@kindex C-x =
+@findex what-cursor-position
+  The command @kbd{C-x =} (@code{what-cursor-position}) provides
+information about point and about the column the cursor is in.
+It prints a line in the echo area that looks like this:
+
+@example
+Char: x (0170)  point=65986 of 563027(12%)  column 44
+@end example
+
+@noindent
+(In fact, this is the output produced when point is before @samp{column 44}
+in the example.)
+
+  The two values after @samp{Char:} describe the character following point,
+first by showing it and second by giving its octal character code.
+
+  @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 invisible, @kbd{C-x =} prints
+additional text describing the current visible range.  For example, it
+might say:
+
+@smallexample
+Char: x (0170)  point=65986 of 563025(12%) <65102 - 68533>  column 44
+@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 visible ones.  @xref{Narrowing}.
+
+  If point is at the end of the buffer (or the end of the visible part),
+@kbd{C-x =} omits any description of the character after point.
+The output looks like
+
+@smallexample
+point=563026 of 563025(100%)  column 0
+@end smallexample
+
+@node Arguments,, Position Info, Basic
+@section Numeric Arguments
+@cindex numeric arguments
+
+  Any Emacs command can be given a @dfn{numeric argument}.  Some commands
+interpret the argument as a repetition count.  For example, giving an
+argument of ten to the key @kbd{C-f} (the command @code{forward-char}, move
+forward one character) moves forward ten characters.  With these commands,
+no argument is equivalent to an argument of one.  Negative arguments are
+allowed.  Often they tell a command to move or act backwards.
+
+@kindex M-1
+@kindex M-@t{-}
+@findex digit-argument
+@findex negative-argument
+  If your keyboard has a @key{META} key (labelled with a diamond on
+Sun-type keyboards and labelled @samp{Alt} on some other keyboards), the
+easiest way to specify a numeric argument is to type digits and/or a
+minus sign while holding down the 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 contribute to an argument for the next command.
+
+@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 shift keys.  To type a negative argument, start with a minus sign.
+Just a minus sign normally means @minus{}1.  @kbd{C-u} works on all terminals.
+
+  @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 frame.  Other useful combinations are @kbd{C-u C-n},
+@kbd{C-u C-u C-n} (move down a good fraction of a frame), @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}.)  Just @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 non-blank 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 will be
+described when they come up; they are always to make the individual
+command more convenient to use.
+
+@c section Autoarg Mode
+@ignore
+@cindex autoarg mode
+  Users of ASCII keyboards may prefer to use Autoarg mode.  Autoarg mode
+means that you don't need to type @kbd{C-u} to specify a numeric argument.
+Instead, you type just the digits.  Digits followed by an ordinary
+inserting character are themselves inserted, but digits followed by an
+Escape or Control character serve as an argument to it and are not
+inserted.  A minus sign can also be part of an argument, but only at the
+beginning.  If you type a minus sign following some digits, both the digits
+and the minus sign are inserted.
+
+  To use Autoarg mode, set the variable Autoarg Mode nonzero.
+@xref{Variables}.
+
+  Autoargument digits echo at the bottom of the frame; the first
+nondigit causes them to be inserted or uses them as an argument.  To
+insert some digits and nothing else, you must follow them with a Space
+and then rub it out.  @kbd{C-g} cancels the digits, while Delete inserts
+them all and then rubs out the last.
+@end ignore