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Each text window's last line is a mode line, which describes what is going on in that window. When there is only one text window, the mode line appears right above the echo area; it is the next-to-last line on the frame. The mode line is in inverse video if the terminal supports that, and it starts and ends with dashes.
Normally, the mode line looks like this:
-cs:ch buf (major minor)--line--pos------
This gives information about the buffer being displayed in the window: the buffer's name, what major and minor modes are in use, whether the buffer's text has been changed, and how far down the buffer you are currently looking.
ch contains two stars `**' if the text in the buffer has
been edited (the buffer is ``modified''), or `--' if the buffer has
not been edited. For a read-only buffer, it is `%*' if the buffer
is modified, and `%%' otherwise.
buf is the name of the window's buffer. In most cases this is the same as the name of a file you are editing. See Buffers.
The buffer displayed in the selected window (the window that the cursor is in) is also Emacs's selected buffer, the one that editing takes place in. When we speak of what some command does to ``the buffer,'' we are talking about the currently selected buffer.
line is `L' followed by the current line number of point.
This is present when Line Number mode is enabled (which it normally is).
You can optionally display the current column number too, by turning on
Column Number mode (which is not enabled by default because it is
somewhat slower). See Optional Mode Line.
pos tells you whether there is additional text above the top of
the window, or below the bottom. If your buffer is small and it is all
visible in the window, pos is `All'. Otherwise, it is
`Top' if you are looking at the beginning of the buffer, `Bot'
if you are looking at the end of the buffer, or `nn%', where
nn is the percentage of the buffer above the top of the
window.
major is the name of the major mode in effect in the buffer. At any time, each buffer is in one and only one of the possible major modes. The major modes available include Fundamental mode (the least specialized), Text mode, Lisp mode, C mode, Texinfo mode, and many others. See Major Modes, for details of how the modes differ and how to select one.
Some major modes display additional information after the major mode name. For example, Rmail buffers display the current message number and the total number of messages. Compilation buffers and Shell buffers display the status of the subprocess.
minor is a list of some of the minor modes that are turned
on at the moment in the window's chosen buffer. For example,
`Fill' means that Auto Fill mode is on. `Abbrev' means that
Word Abbrev mode is on. `Ovwrt' means that Overwrite mode is on.
See Minor Modes, for more information. `Narrow' means that the
buffer being displayed has editing restricted to only a portion of its
text. This is not really a minor mode, but is like one.
See Narrowing. `Def' means that a keyboard macro is being
defined. See Keyboard Macros.
In addition, if Emacs is currently inside a recursive editing level,
square brackets (`[...]') appear around the parentheses that
surround the modes. If Emacs is in one recursive editing level within
another, double square brackets appear, and so on. Since recursive
editing levels affect Emacs globally, not just one buffer, the square
brackets appear in every window's mode line or not in any of them.
See Recursive Edit.
Non-windowing terminals can only show a single Emacs frame at a time
(see Frames). On such terminals, the mode line displays the name of
the selected frame, after ch. The initial frame's name is
`F1'.
cs states the coding system used for the file you are editing.
A dash indicates the default state of affairs: no code conversion,
except for end-of-line translation if the file contents call for that.
`=' means no conversion whatsoever. Nontrivial code conversions
are represented by various letters---for example, `1' refers to ISO
Latin-1. See Coding Systems, for more information. If you are using
an input method, a string of the form `i>' is added to the
beginning of cs; i identifies the input method. (Some input
methods show `+' or `@' instead of `>'.) See Input Methods.
When you are using a character-only terminal (not a window system), cs uses three characters to describe, respectively, the coding system for keyboard input, the coding system for terminal output, and the coding system used for the file you are editing.
When multibyte characters are not enabled, cs does not appear at all. See Enabling Multibyte.
The colon after cs can change to another string in certain
circumstances. Emacs uses newline to separate lines in the buffer.
Some files use different conventions for separating lines: either
carriage-return linefeed (the MS-DOS convention) or just carriage-return
(the Macintosh convention). If the buffer's file uses carriage-return
linefeed, the colon changes to either a backslash (`\') or
`(DOS)', depending on the operating system. If the file uses just
carriage-return, the colon indicator changes to either a forward slash
(`/') or `(Mac)'. On some systems, Emacs displays
`(Unix)' instead of the colon even for files that use newline to
separate lines.
You can customize the mode line display for each of the end-of-line
formats by setting each of the variables eol-mnemonic-unix,
eol-mnemonic-dos, eol-mnemonic-mac, and
eol-mnemonic-undecided to any string you find appropriate.
See Variables, for an explanation how to set variables.
See Optional Mode Line, for features that add other handy information to the mode line, such as the current column number of point, the current time, and whether new mail for you has arrived.
Echo Area
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