+File: xemacs.info, Node: Position Info, Next: Arguments, Prev: Continuation Lines, Up: Basic
+
+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.
+
+`M-x what-page'
+ Print page number of point, and line number within page.
+
+`M-x what-line'
+ Print line number of point in the buffer.
+
+`M-x line-number-mode'
+ Toggle automatic display of current line number.
+
+`M-='
+ Print number of lines and characters in the current region
+ (`count-lines-region'). *Note Mark::, for information about the
+ region.
+
+`C-x ='
+ Print character code of character after point, character position
+ of point, and column of point (`what-cursor-position').
+
+ There are several commands for printing line numbers:
+
+ * `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 `M-x
+ goto-line'.
+
+ * `M-x what-page' counts pages from the beginning of the file, and
+ counts lines within the page, printing both of them. *Note
+ Pages::, for the command `C-x l', which counts the lines in the
+ current page.
+
+ * `M-=' (`count-lines-region') prints the number of lines in the
+ region (*note Mark::). *Note Pages::, for the command `C-x l'
+ which counts the lines in the
+
+ The command `C-x =' (`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:
+
+ Char: c (0143, 99, 0x63) point=18862 of 24800(76%) column 53
+
+(In fact, this is the output produced when point is before `column 53'
+in the example.)
+
+ The four values after `Char:' describe the character that follows
+point, first by showing it and then by giving its character code in
+octal, decimal and hex.
+
+ `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.
+
+ `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, `C-x =' prints additional
+text describing the current visible range. For example, it might say:
+
+ Char: c (0143, 99, 0x63) point=19674 of 24575(80%) <19591 - 19703> column 69
+
+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. *Note Narrowing::.
+
+ If point is at the end of the buffer (or the end of the visible
+part), `C-x =' omits any description of the character after point. The
+output looks like
+
+ point=563026 of 563025(100%) column 0
+
+\1f
+File: xemacs.info, Node: Arguments, Prev: Position Info, Up: Basic
+
+Numeric Arguments
+=================
+
+ In mathematics and computer usage, the word "argument" means "data
+provided to a function or operation." Any Emacs command can be given a
+"numeric argument" (also called a "prefix argument"). Some commands
+interpret the argument as a repetition count. For example, giving an
+argument of ten to the key `C-f' (the command `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 in
+the opposite direction.
+
+ If your keyboard has a <META> key (labelled with a diamond on
+Sun-type keyboards and labelled `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 <META> key. For example,
+ M-5 C-n
+
+would move down five lines. The characters `Meta-1', `Meta-2', and so
+on, as well as `Meta--', do this because they are keys bound to
+commands (`digit-argument' and `negative-argument') that are defined to
+contribute to an argument for the next command. Digits and `-'
+modified with Control, or Control and Meta, also specify numeric
+arguments.
+
+ Another way of specifying an argument is to use the `C-u'
+(`universal-argument') command followed by the digits of the argument.
+With `C-u', you can type the argument digits without holding down
+modifier keys; `C-u' works on all terminals. To type a negative
+argument, type a minus sign after `C-u'. Just a minus sign without
+digits normally means -1.
+
+ `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. `C-u' twice multiplies it by
+sixteen. Thus, `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 `C-u C-n', `C-u
+C-u C-n' (move down a good fraction of a frame), `C-u C-u C-o' (make "a
+lot" of blank lines), and `C-u C-k' (kill four lines).
+
+ Some commands care only about whether there is an argument and not
+about its value. For example, the command `M-q' (`fill-paragraph') with
+no argument fills text; with an argument, it justifies the text as well.
+(*Note Filling::, for more information on `M-q'.) Just `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
+`C-k' (`kill-line') with argument N kills N lines, including their
+terminating newlines. But `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 `C-k' commands with
+no arguments can kill a non-blank line, just like `C-k' with an
+argument of one. (*Note Killing::, for more information on `C-k'.)
+
+ A few commands treat a plain `C-u' differently from an ordinary
+argument. A few others may treat an argument of just a minus sign
+differently from an argument of -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, `C-u 6 4 a' inserts 64 copies of the character `a'. But this
+does not work for inserting digits; `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 `C-u'; for example, `C-u 6 4 C-u
+1' does insert 64 copies of the character `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.
+
+\1f
+File: xemacs.info, Node: Undo, Next: Minibuffer, Prev: Basic, Up: Top
+
+Undoing Changes
+***************
+
+ Emacs allows you to undo all changes you make to the text of a
+buffer, up to a certain amount of change (8000 characters). 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
+`query-replace' make many entries, and very simple commands such as
+self-inserting characters are often grouped to make undoing less
+tedious.
+
+`C-x u'
+ Undo one batch of changes (usually, one command's worth) (`undo').
+
+`C-_'
+ The same.
+
+ The command `C-x u' or `C-_' allows you to undo changes. The first
+time you give this command, it undoes the last change. Point moves to
+the text affected by the undo, so you can see what was undone.
+
+ Consecutive repetitions of the `C-_' or `C-x u' commands undo
+earlier and earlier changes, back to the limit of what has been
+recorded. 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 at this moment, the previous undo commands are
+considered ordinary changes that can themselves be undone. Thus, you
+can redo changes you have undone by typing `C-f' or any other command
+that have no important effect, and then using more undo commands.
+
+ If you notice that a buffer has been modified accidentally, the
+easiest way to recover is to type `C-_' repeatedly until the stars
+disappear from the front of the mode line. When that happens, all the
+modifications you made have been canceled. If you do not remember
+whether you changed the buffer deliberately, type `C-_' once. When you
+see Emacs undo the last change you made, you probably remember why you
+made it. If the change was an accident, leave it undone. If it was
+deliberate, redo the change as described in the preceding paragraph.
+
+ Whenever an undo command makes the stars disappear from the mode
+line, the buffer contents is the same as it was when the file was last
+read in or saved.
+
+ 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.
+Minibuffers, help buffers, and documentation buffers also don't record
+undo information.
+
+ Emacs can remember at most 8000 or so characters of deleted or
+modified text in any one buffer for reinsertion by the undo command.
+There is also a limit on the number of individual insert, delete, or
+change actions that Emacs can remember.
+
+ There are two keys to run the `undo' command, `C-x u' and `C-_',
+because on some keyboards, it is not obvious how to type `C-_'. `C-x u'
+is an alternative you can type in the same fashion on any terminal.
+
+\1f
+File: xemacs.info, Node: Minibuffer, Next: M-x, Prev: Undo, Up: Top
+
+The Minibuffer
+**************
+
+ The "minibuffer" is the facility used by XEmacs commands to read
+arguments more complicated than a single number. Minibuffer arguments
+can be file names, buffer names, Lisp function names, XEmacs command
+names, Lisp expressions, and many other things, depending on the command
+reading the argument. You can use the usual XEmacs editing commands in
+the minibuffer to edit the argument text.
+
+ When the minibuffer is in use, it appears in the echo area, and the
+cursor moves there. The beginning of the minibuffer line displays a
+"prompt" which says what kind of input you should supply and how it
+will be used. Often this prompt is derived from the name of the command
+that the argument is for. The prompt normally ends with a colon.
+
+ Sometimes a "default argument" appears in parentheses after the
+colon; it, too, is part of the prompt. The default is used as the
+argument value if you enter an empty argument (e.g., by just typing
+<RET>). For example, commands that read buffer names always show a
+default, which is the name of the buffer that will be used if you type
+just <RET>.
+
+ The simplest way to enter a minibuffer argument is to type the text
+you want, terminated by <RET> which exits the minibuffer. You can
+cancel the command that wants the argument, and get out of the
+minibuffer, by typing `C-g'.
+
+ Since the minibuffer uses the screen space of the echo area, it can
+conflict with other ways XEmacs customarily uses the echo area. Here is
+how XEmacs handles such conflicts:
+
+ * If a command gets an error while you are in the minibuffer, this
+ does not cancel the minibuffer. However, the echo area is needed
+ for the error message and therefore the minibuffer itself is
+ hidden for a while. It comes back after a few seconds, or as soon
+ as you type anything.
+
+ * If in the minibuffer you use a command whose purpose is to print a
+ message in the echo area, such as `C-x =', the message is printed
+ normally, and the minibuffer is hidden for a while. It comes back
+ after a few seconds, or as soon as you type anything.
+
+ * Echoing of keystrokes does not take place while the minibuffer is
+ in use.
+
+* Menu:
+
+* File: Minibuffer File. Entering file names with the minibuffer.
+* Edit: Minibuffer Edit. How to edit in the minibuffer.
+* Completion:: An abbreviation facility for minibuffer input.
+* Minibuffer History:: Reusing recent minibuffer arguments.
+* Repetition:: Re-executing commands that used the minibuffer.
+
+\1f
+File: xemacs.info, Node: Minibuffer File, Next: Minibuffer Edit, Prev: Minibuffer, Up: Minibuffer
+
+Minibuffers for File Names
+==========================
+
+ Sometimes the minibuffer starts out with text in it. For example,
+when you are supposed to give a file name, the minibuffer starts out
+containing the "default directory", which ends with a slash. This is
+to inform you which directory the file will be found in if you do not
+specify a directory.
+
+ For example, the minibuffer might start out with these contents:
+
+ Find File: /u2/emacs/src/
+
+where `Find File: ' is the prompt. Typing `buffer.c' specifies the
+file `/u2/emacs/src/buffer.c'. To find files in nearby directories,
+use `..'; thus, if you type `../lisp/simple.el', you will get the file
+named `/u2/emacs/lisp/simple.el'. Alternatively, you can kill with
+`M-<DEL>' the directory names you don't want (*note Words::).
+
+ If you don't want any of the default, you can kill it with `C-a
+C-k'. But you don't need to kill the default; you can simply ignore it.
+Insert an absolute file name, one starting with a slash or a tilde,
+after the default directory. For example, to specify the file
+`/etc/termcap', just insert that name, giving these minibuffer contents:
+
+ Find File: /u2/emacs/src//etc/termcap
+
+XEmacs gives a special meaning to a double slash (which is not normally
+a useful thing to write): it means, "ignore everything before the
+second slash in the pair." Thus, `/u2/emacs/src/' is ignored in the
+example above, and you get the file `/etc/termcap'.
+
+ If you set `insert-default-directory' to `nil', the default
+directory is not inserted in the minibuffer. This way, the minibuffer
+starts out empty. But the name you type, if relative, is still
+interpreted with respect to the same default directory.
+
+\1f
+File: xemacs.info, Node: Minibuffer Edit, Next: Completion, Prev: Minibuffer File, Up: Minibuffer
+
+Editing in the Minibuffer
+=========================
+
+ The minibuffer is an XEmacs buffer (albeit a peculiar one), and the
+usual XEmacs commands are available for editing the text of an argument
+you are entering.
+
+ Since <RET> in the minibuffer is defined to exit the minibuffer, you
+can't use it to insert a newline in the minibuffer. To do that, type
+`C-o' or `C-q C-j'. (Recall that a newline is really the character
+control-J.)
+
+ The minibuffer has its own window which always has space on the
+screen but acts as if it were not there when the minibuffer is not in
+use. When the minibuffer is in use, its window is just like the
+others; you can switch to another window with `C-x o', edit text in
+other windows and perhaps even visit more files, before returning to the
+minibuffer to submit the argument. You can kill text in another window,
+return to the minibuffer window, and then yank the text to use it in the
+argument. *Note Windows::.
+
+ There are some restrictions on the use of the minibuffer window,
+however. You cannot switch buffers in it--the minibuffer and its
+window are permanently attached. Also, you cannot split or kill the
+minibuffer window. But you can make it taller in the normal fashion with
+`C-x ^'. If you enable Resize-Minibuffer mode, then the minibuffer
+window expands vertically as necessary to hold the text that you put in
+the minibuffer. Use `M-x resize-minibuffer-mode' to enable or disable
+this minor mode (*note Minor Modes::).
+
+ If while in the minibuffer you issue a command that displays help
+text of any sort in another window, you can use the `C-M-v' command
+while in the minibuffer to scroll the help text. This lasts until you
+exit the minibuffer. This feature is especially useful if a completing
+minibuffer gives you a list of possible completions. *Note Other
+Window::.
+
+ If the variable `minibuffer-confirm-incomplete' is `t', you are
+asked for confirmation if there is no known completion for the text you
+typed. For example, if you attempted to visit a non-existent file, the
+minibuffer might read:
+ Find File: chocolate_bar.c [no completions, confirm]
+ If you press `Return' again, that confirms the filename. Otherwise,
+you can continue editing it.
+
+ XEmacs supports recursive use of the minibuffer. However, it is easy
+to do this by accident (because of autorepeating keyboards, for example)
+and get confused. Therefore, most XEmacs commands that use the
+minibuffer refuse to operate if the minibuffer window is selected. If
+the minibuffer is active but you have switched to a different window,
+recursive use of the minibuffer is allowed--if you know enough to try
+to do this, you probably will not get confused.
+
+ If you set the variable `enable-recursive-minibuffers' to a
+non-`nil', recursive use of the minibuffer is always allowed.
+
+\1f
projects / chise / xemacs-chise.git- / blobdiff