mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-28 07:45:00 +00:00
918 lines
38 KiB
Plaintext
918 lines
38 KiB
Plaintext
Copyright (c) 1985 Free Software Foundation, Inc; See end for conditions.
|
|
You are looking at the Emacs tutorial.
|
|
|
|
Emacs commands generally involve the CONTROL key (sometimes labeled
|
|
CTRL or CTL) or the META key (sometimes labeled EDIT or ALT). Rather than
|
|
write that in full each time, we'll use the following abbreviations:
|
|
|
|
C-<chr> means hold the CONTROL key while typing the character <chr>
|
|
Thus, C-f would be: hold the CONTROL key and type f.
|
|
M-<chr> means hold the META or EDIT or ALT key down while typing <chr>.
|
|
If there is no META, EDIT or ALT key, instead press and release the
|
|
ESC key and then type <chr>. We write <ESC> for the ESC key.
|
|
|
|
Important note: to end the Emacs session, type C-x C-c. (Two characters.)
|
|
The characters ">>" at the left margin indicate directions for you to
|
|
try using a command. For instance:
|
|
<<Blank lines inserted here by startup of help-with-tutorial>>
|
|
>> Now type C-v (View next screen) to move to the next screen.
|
|
(go ahead, do it by depressing the control key and v together).
|
|
From now on, you'll be expected to do this whenever you finish
|
|
reading the screen.
|
|
|
|
Note that there is an overlap when going from screen to screen; this
|
|
provides some continuity when moving through the file.
|
|
|
|
The first thing that you need to know is how to move around from
|
|
place to place in the file. You already know how to move forward a
|
|
screen, with C-v. To move backwards a screen, type M-v (depress the
|
|
META key and type v, or type <ESC>v if you don't have a META or EDIT
|
|
key).
|
|
|
|
>> Try typing M-v and then C-v to move back and forth a few times.
|
|
|
|
|
|
* SUMMARY
|
|
---------
|
|
|
|
The following commands are useful for viewing screenfuls:
|
|
|
|
C-v Move forward one screenful
|
|
M-v Move backward one screenful
|
|
C-l Clear screen and redisplay everything
|
|
putting the text near the cursor at the center.
|
|
(That's control-L, not control-1.)
|
|
|
|
>> Find the cursor and remember what text is near it.
|
|
Then type a C-l.
|
|
Find the cursor again and see what text is near it now.
|
|
|
|
|
|
* BASIC CURSOR CONTROL
|
|
----------------------
|
|
|
|
Getting from screenful to screenful is useful, but how do you
|
|
reposition yourself within a given screen to a specific place?
|
|
There are several ways you can do this. One way (not the best, but
|
|
the most basic) is to use the commands previous, backward, forward
|
|
and next. As you can imagine these commands (which are given to
|
|
Emacs as C-p, C-b, C-f, and C-n respectively) move the cursor from
|
|
where it currently is to a new place in the given direction. Here,
|
|
in a more graphical form are the commands:
|
|
|
|
Previous line, C-p
|
|
:
|
|
:
|
|
Backward, C-b .... Current cursor position .... Forward, C-f
|
|
:
|
|
:
|
|
Next line, C-n
|
|
|
|
>> Move the cursor to the line in the middle of that diagram
|
|
and type C-l to see the whole diagram centered in the screen.
|
|
|
|
You'll probably find it easy to think of these by letter. P for
|
|
previous, N for next, B for backward and F for forward. These are
|
|
the basic cursor positioning commands and you'll be using them ALL
|
|
the time so it would be of great benefit if you learn them now.
|
|
|
|
>> Do a few C-n's to bring the cursor down to this line.
|
|
|
|
>> Move into the line with C-f's and then up with C-p's.
|
|
See what C-p does when the cursor is in the middle of the line.
|
|
|
|
Lines are separated by Newline characters. For most applications
|
|
there should normally be a Newline character at the end of the text,
|
|
as well, but it is up to you to make sure of this. A file can
|
|
validly exist without a Newline at the end.
|
|
|
|
>> Try to C-b at the beginning of a line. Do a few more C-b's.
|
|
Then do C-f's back to the end of the line and beyond.
|
|
|
|
When you go off the top or bottom of the screen, the text beyond
|
|
the edge is shifted onto the screen so that your instructions can
|
|
be carried out while keeping the cursor on the screen.
|
|
|
|
>> Try to move the cursor off the bottom of the screen with C-n and
|
|
see what happens.
|
|
|
|
If moving by characters is too slow, you can move by words. M-f
|
|
(Meta-f) moves forward a word and M-b moves back a word.
|
|
|
|
>> Type a few M-f's and M-b's. Intersperse them with C-f's and C-b's.
|
|
|
|
Notice the parallel between C-f and C-b on the one hand, and M-f and
|
|
M-b on the other hand. Very often Meta characters are used for
|
|
operations related to English text whereas Control characters operate
|
|
on the basic textual units that are independent of what you are
|
|
editing (characters, lines, etc). There is a similar parallel between
|
|
lines and sentences: C-a and C-e move to the beginning or end of a
|
|
line, and M-a and M-e move to the beginning or end of a sentence.
|
|
|
|
>> Try a couple of C-a's, and then a couple of C-e's.
|
|
Try a couple of M-a's, and then a couple of M-e's.
|
|
|
|
See how repeated C-a's do nothing, but repeated M-a's keep moving
|
|
farther. Do you think that this is right?
|
|
|
|
Two other simple cursor motion commands are M-< (Meta Less-than),
|
|
which moves to the beginning of the file, and M-> (Meta Greater-than),
|
|
which moves to the end of the file. You probably don't need to try
|
|
them, since finding this spot again will be boring. On most terminals
|
|
the "<" is above the comma and you must use the shift key to type it.
|
|
On these terminals you must use the shift key to type M-< also;
|
|
without the shift key, you would be typing M-comma.
|
|
|
|
The location of the cursor in the text is also called "point". To
|
|
paraphrase, the cursor shows on the screen where point is located in
|
|
the text.
|
|
|
|
Here is a summary of simple moving operations including the word and
|
|
sentence moving commands:
|
|
|
|
C-f Move forward a character
|
|
C-b Move backward a character
|
|
|
|
M-f Move forward a word
|
|
M-b Move backward a word
|
|
|
|
C-n Move to next line
|
|
C-p Move to previous line
|
|
|
|
C-a Move to beginning of line
|
|
C-e Move to end of line
|
|
|
|
M-a Move back to beginning of sentence
|
|
M-e Move forward to end of sentence
|
|
|
|
M-< Go to beginning of file
|
|
M-> Go to end of file
|
|
|
|
>> Try all of these commands now a few times for practice.
|
|
Since the last two will take you away from this screen,
|
|
you can come back here with M-v's and C-v's. These are
|
|
the most often used commands.
|
|
|
|
Like all other commands in Emacs, these commands can be given
|
|
arguments which cause them to be executed repeatedly. The way you
|
|
give a command a repeat count is by typing C-u and then the digits
|
|
before you type the command. If you have a META or EDIT key, you can
|
|
omit the C-u if you hold down the META or EDIT key while you type the
|
|
digits. This is easier, but we recommend the C-u method because it
|
|
works on any terminal.
|
|
|
|
For instance, C-u 8 C-f moves forward eight characters.
|
|
|
|
>> Try giving a suitable argument to C-n or C-p to come as close
|
|
as you can to this line in one jump.
|
|
|
|
The only apparent exception to this is the screen moving commands,
|
|
C-v and M-v. When given an argument, they scroll the screen up or
|
|
down by that many lines, rather than screenfuls. This proves to be
|
|
much more useful.
|
|
|
|
>> Try typing C-u 8 C-v now.
|
|
|
|
Did it scroll the screen up by 8 lines? If you would like to
|
|
scroll it down you can give an argument to M-v.
|
|
|
|
If you are using X Windows, there is probably a rectangular area
|
|
called a scroll bar at the right hand side of the Emacs window. You
|
|
can scroll the text by clicking the mouse in the scroll bar.
|
|
|
|
>> Try pressing the middle button at the top of the highlighted area
|
|
within the scroll bar, then moving the mouse while holding that button
|
|
down.
|
|
|
|
>> Move the mouse to a point in the scroll bar about three lines from
|
|
the top, and click the left button a couple of times. Then try the
|
|
right button a couple of times.
|
|
|
|
|
|
* WHEN EMACS IS HUNG
|
|
--------------------
|
|
|
|
If Emacs gets into an infinite (or simply very long) computation which
|
|
you don't want to finish, you can stop it safely by typing C-g.
|
|
You can also use C-g to discard a numeric argument or the beginning of
|
|
a command that you don't want to finish.
|
|
|
|
>> Type C-u 100 to make a numeric arg of 100, then type C-g.
|
|
Now type C-f. How many characters does it move?
|
|
If you have typed an <ESC> by mistake, you can get rid of it
|
|
with a C-g.
|
|
|
|
If you type <ESC> : then you get a new window appearing on the screen,
|
|
telling you that M-: is a "disabled command" and asking whether you
|
|
really want to execute it. The command M-: is marked as disabled
|
|
because we expect it would confuse beginners and you probably don't
|
|
want to use it until you know more about Emacs. If you really want to
|
|
try the M-: command, you could type a Space in answer to the question,
|
|
and M-: would go ahead. Normally, if you do not want to execute M-:,
|
|
you would type "n" to answer the question.
|
|
|
|
>> Type <ESC> :, then type n.
|
|
|
|
|
|
* WINDOWS
|
|
---------
|
|
|
|
Emacs can have several windows, each displaying its own text.
|
|
At this stage it is better not to go into the techniques of
|
|
using multiple windows. But you do need to know how to get
|
|
rid of extra windows that may appear to display help or
|
|
output from certain commands. It is simple:
|
|
|
|
C-x 1 One window (i.e., kill all other windows).
|
|
|
|
That is Control-x followed by the digit 1.
|
|
C-x 1 makes the window which the cursor is in become
|
|
the full screen, by getting rid of any other windows.
|
|
|
|
>> Move the cursor to this line and type C-u 0 C-l.
|
|
>> Type Control-h k Control-f.
|
|
See how this window shrinks, while a new one appears
|
|
to display documentation on the Control-f command.
|
|
|
|
>> Type C-x 1 and see the documentation listing window disappear.
|
|
|
|
|
|
* INSERTING AND DELETING
|
|
------------------------
|
|
|
|
If you want to insert text, just type it. Characters which you can
|
|
see, such as A, 7, *, etc. are taken by Emacs as text and inserted
|
|
immediately. Type <Return> (the carriage-return key) to insert a
|
|
Newline character.
|
|
|
|
You can delete the last character you typed by typing <Delete>.
|
|
<Delete> is a key on the keyboard, which may be labeled "Del". In
|
|
some cases, the "Backspace" key serves as <Delete>, but not always!
|
|
|
|
More generally, <Delete> deletes the character immediately before the
|
|
current cursor position.
|
|
|
|
>> Do this now, type a few characters and then delete them
|
|
by typing <Delete> a few times. Don't worry about this file
|
|
being changed; you won't affect the master tutorial. This is just
|
|
a copy of it.
|
|
|
|
>> Now start typing text until you reach the right margin, and keep
|
|
typing. When a line of text gets too big for one line on the
|
|
screen, the line of text is "continued" onto a second screen line.
|
|
The backslash at the right margin indicates a line which has
|
|
been continued.
|
|
>> Use <Delete>s to delete the text until the line fits on one screen
|
|
line again. The continuation line goes away.
|
|
|
|
>> Move the cursor to the beginning of a line and type <Delete>. This
|
|
deletes the newline before the line and merges the line onto
|
|
the previous line. The resulting line may be too long to fit, in
|
|
which case it has a continuation line.
|
|
>> Type <Return> to reinsert the Newline you deleted.
|
|
|
|
Remember that most Emacs commands can be given a repeat count;
|
|
this includes characters which insert themselves.
|
|
|
|
>> Try that now -- type C-u 8 * and see what happens.
|
|
|
|
You've now learned the most basic way of typing something in
|
|
Emacs and correcting errors. You can delete by words or lines
|
|
as well. Here is a summary of the delete operations:
|
|
|
|
<Delete> delete the character just before the cursor
|
|
C-d delete the next character after the cursor
|
|
|
|
M-<Delete> kill the word immediately before the cursor
|
|
M-d kill the next word after the cursor
|
|
|
|
C-k kill from the cursor position to end of line
|
|
M-k kill to the end of the current sentence
|
|
|
|
Notice that <Delete> and C-d vs M-<Delete> and M-d extend the parallel
|
|
started by C-f and M-f (well, <Delete> isn't really a control
|
|
character, but let's not worry about that). C-k and M-k are like C-e
|
|
and M-e, sort of, in that lines are opposite sentences.
|
|
|
|
Now suppose you kill something, and then you decide that you want to
|
|
get it back? Well, whenever you kill something bigger than a
|
|
character, Emacs saves it for you. To yank it back, use C-y. You
|
|
can kill text in one place, move elsewhere, and then do C-y; this is
|
|
a good way to move text around. Note that the difference
|
|
between "Killing" and "Deleting" something is that "Killed" things
|
|
can be yanked back, and "Deleted" things cannot. Generally, the
|
|
commands that can destroy a lot of text save it, while the ones that
|
|
attack only one character, or nothing but blank lines and spaces, do
|
|
not save.
|
|
|
|
For instance, type C-n a couple times to position the cursor
|
|
at some line on this screen.
|
|
|
|
>> Do this now, move the cursor and kill that line with C-k.
|
|
|
|
Note that a single C-k kills the contents of the line, and a second
|
|
C-k kills the line itself, and make all the other lines move up. If
|
|
you give C-k a repeat count, it kills that many lines AND their
|
|
contents.
|
|
|
|
The text that has just disappeared is saved so that you can
|
|
retrieve it. To retrieve the last killed text and put it where
|
|
the cursor currently is, type C-y.
|
|
|
|
>> Try it; type C-y to yank the text back.
|
|
|
|
Think of C-y as if you were yanking something back that someone
|
|
took away from you. Notice that if you do several C-k's in a row
|
|
the text that is killed is all saved together so that one C-y will
|
|
yank all of the lines.
|
|
|
|
>> Do this now, type C-k several times.
|
|
|
|
Now to retrieve that killed text:
|
|
|
|
>> Type C-y. Then move the cursor down a few lines and type C-y
|
|
again. You now see how to copy some text.
|
|
|
|
What do you do if you have some text you want to yank back, and then
|
|
you kill something else? C-y would yank the more recent kill. But
|
|
the previous text is not lost. You can get back to it using the M-y
|
|
command. After you have done C-y to get the most recent kill, typing
|
|
M-Y replaces that yanked text with the previous kill. Typing M-y
|
|
again and again brings in earlier and earlier kills. When you
|
|
have reached the text you are looking for, you can just go away and
|
|
leave it there. If you M-y enough times, you come back to the
|
|
starting point (the most recent kill).
|
|
|
|
>> Kill a line, move around, kill another line.
|
|
Then do C-y to get back the second killed line.
|
|
Then do M-y and it will be replaced by the first killed line.
|
|
Do more M-y's and see what you get. Keep doing them until
|
|
the second kill line comes back, and then a few more.
|
|
If you like, you can try giving M-y positive and negative
|
|
arguments.
|
|
|
|
|
|
* UNDO
|
|
------
|
|
|
|
Any time you make a change to the text and wish you had not done so,
|
|
you can undo the change (return the text to its previous state)
|
|
with the undo command, C-x u. Normally, C-x u undoes one command's
|
|
worth of changes; if you repeat the C-x u several times in a row,
|
|
each time undoes one more command. There are two exceptions:
|
|
commands that made no change (just moved the cursor) do not count,
|
|
and self-inserting characters are often lumped together in groups
|
|
of up to 20. This is to reduce the number of C-x u's you have to type.
|
|
|
|
>> Kill this line with C-k, then type C-x u and it should reappear.
|
|
|
|
C-_ is another command for undoing; it is just the same as C-x u
|
|
but easier to type several times in a row. The problem with C-_ is
|
|
that on some keyboards it is not obvious how to type it. That is
|
|
why C-x u is provided as well. On some DEC terminals, you can type
|
|
C-_ by typing / while holding down CTRL. Illogical, but what can
|
|
you expect from DEC?
|
|
|
|
Giving a numeric argument to C-_ or C-x u is equivalent to repeating
|
|
it as many times as the argument says.
|
|
|
|
|
|
* FILES
|
|
-------
|
|
|
|
In order to make the text you edit permanent, you must put it in a
|
|
file. Otherwise, it will go away when your invocation of Emacs goes
|
|
away. You put your editing in a file by "finding" the file. What
|
|
finding means is that you see the contents of the file in your Emacs;
|
|
and, loosely speaking, what you are editing is the file itself.
|
|
However, the changes still don't become permanent until you "save" the
|
|
file. This is so you can have control to avoid leaving a half-changed
|
|
file around when you don't want to. Even then, Emacs leaves the
|
|
original file under a changed name in case your changes turn out
|
|
to be a mistake.
|
|
|
|
If you look near the bottom of the screen you will see a line that
|
|
begins and ends with dashes, and contains the string "Emacs: TUTORIAL".
|
|
Your copy of the Emacs tutorial is called "TUTORIAL". Whatever
|
|
file you find, that file's name will appear in that precise
|
|
spot.
|
|
|
|
The commands for finding and saving files are unlike the other
|
|
commands you have learned in that they consist of two characters.
|
|
They both start with the character Control-x. There is a whole series
|
|
of commands that start with Control-x; many of them have to do with
|
|
files, buffers, and related things, and all of them consist of
|
|
Control-x followed by some other character.
|
|
|
|
Another thing about the command for finding a file is that you have
|
|
to say what file name you want. We say the command "reads an argument
|
|
from the terminal" (in this case, the argument is the name of the
|
|
file). After you type the command
|
|
|
|
C-x C-f Find a file
|
|
|
|
Emacs asks you to type the file name. It echoes on the bottom
|
|
line of the screen. You are using the minibuffer now! this is
|
|
what the minibuffer is for. When you type <Return> to end the
|
|
file name, the minibuffer is no longer needed, so it disappears.
|
|
|
|
>> Type C-x C-f, then type C-g. This cancels the minibuffer,
|
|
and also cancels the C-x C-f command that was using the
|
|
minibuffer. So you do not find any file.
|
|
|
|
In a little while the file contents appear on the screen. You can
|
|
edit the contents. When you wish to make the changes permanent,
|
|
issue the command
|
|
|
|
C-x C-s Save the file
|
|
|
|
The contents of Emacs are written into the file. The first time you
|
|
do this, the original file is renamed to a new name so that it
|
|
is not lost. The new name is made by appending "~" to the end
|
|
of the original file's name.
|
|
|
|
When saving is finished, Emacs prints the name of the file written.
|
|
You should save fairly often, so that you will not lose very much
|
|
work if the system should crash.
|
|
|
|
>> Type C-x C-s, saving your copy of the tutorial.
|
|
This should print "Wrote .../TUTORIAL" at the bottom of the screen.
|
|
On VMS it will print "Wrote ...[...]TUTORIAL."
|
|
|
|
NOTE: On some systems, typing C-x C-s will freeze the screen and you
|
|
will see no further output from Emacs. This indicates that an
|
|
operating system "feature" called "flow control" is intercepting the
|
|
C-s and not letting it get through to Emacs. To unfreeze the screen,
|
|
type C-q. Then see the section "Spontaneous Entry to Incremental
|
|
Search" in the Emacs manual for advice on dealing with this "feature".
|
|
|
|
To make a new file, just find it "as if" it already existed. Then
|
|
start typing in the text. When you ask to "save" the file, Emacs
|
|
will really create the file with the text that you have inserted.
|
|
From then on, you can consider yourself to be editing an already
|
|
existing file.
|
|
|
|
|
|
* BUFFERS
|
|
---------
|
|
|
|
If you find a second file with C-x C-f, the first file remains
|
|
inside Emacs. You can switch back to it by finding it again with
|
|
C-x C-f. This way you can get quite a number of files inside Emacs.
|
|
|
|
The object inside Emacs which holds the text read from one file
|
|
is called a "buffer." Finding a file makes a new buffer inside Emacs.
|
|
To see a list of the buffers that exist in Emacs, type
|
|
|
|
C-x C-b List buffers
|
|
|
|
>> Try C-x C-b now.
|
|
|
|
See how each buffer has a name, and it may also have a file name
|
|
for the file whose contents it holds. Some buffers do not correspond
|
|
to files. For example, the buffer named "*Buffer List*" does
|
|
not have any file. It is the buffer which contains the buffer
|
|
list that was made by C-x C-b. ANY text you see in an Emacs window
|
|
has to be in some buffer.
|
|
|
|
>> Type C-x 1 to get rid of the buffer list.
|
|
|
|
If you make changes to the text of one file, then find another file,
|
|
this does not save the first file. Its changes remain inside Emacs,
|
|
in that file's buffer. The creation or editing of the second file's
|
|
buffer has no effect on the first file's buffer. This is very useful,
|
|
but it also means that you need a convenient way to save the first
|
|
file's buffer. It would be a nuisance to have to switch back to
|
|
it with C-x C-f in order to save it with C-x C-s. So we have
|
|
|
|
C-x s Save some buffers
|
|
|
|
C-x s goes through the list of all the buffers you have
|
|
and finds the ones that contain files you have changed.
|
|
For each such buffer, C-x s asks you whether to save it.
|
|
|
|
|
|
* EXTENDING THE COMMAND SET
|
|
---------------------------
|
|
|
|
There are many, many more Emacs commands than could possibly be put
|
|
on all the control and meta characters. Emacs gets around this with
|
|
the X (eXtend) command. This comes in two flavors:
|
|
|
|
C-x Character eXtend. Followed by one character.
|
|
M-x Named command eXtend. Followed by a long name.
|
|
|
|
These are commands that are generally useful but used less than the
|
|
commands you have already learned about. You have already seen two
|
|
of them: the file commands C-x C-f to Find and C-x C-s to Save.
|
|
Another example is the command to tell Emacs that you'd like to stop
|
|
editing and get rid of Emacs. The command to do this is C-x C-c.
|
|
(Don't worry; it offers to save each changed file before it kills the
|
|
Emacs.)
|
|
|
|
C-z is the command to exit Emacs *temporarily*--so that you can go
|
|
back to the same Emacs session afterward.
|
|
|
|
On systems which allow it, C-z exits from Emacs to the shell but does
|
|
not destroy the Emacs; if you use the C shell, you can resume Emacs
|
|
with the `fg' command (or, more generally, with `%emacs', which works
|
|
even if your most recent job was some other). On systems which don't
|
|
implement suspending, C-z creates a subshell running under Emacs to
|
|
give you the chance to run other programs and return to Emacs
|
|
afterward; it does not truly "exit" from Emacs. In this case, the
|
|
shell command `exit' is the usual way to get back to Emacs from the
|
|
subshell.
|
|
|
|
The time to use C-x C-c is when you are about to log out. It's also
|
|
the right thing to use to exit an Emacs invoked under mail handling
|
|
programs and other random utilities, since they may not know how to
|
|
cope with suspension of Emacs. On other occasions, use C-z, and
|
|
resume the Emacs when you have more editing to do.
|
|
|
|
There are many C-x commands. The ones you know are:
|
|
|
|
C-x C-f Find file.
|
|
C-x C-s Save file.
|
|
C-x C-b List buffers.
|
|
C-x C-c Quit Emacs.
|
|
C-x u Undo.
|
|
|
|
Named eXtended commands are commands which are used even less
|
|
frequently, or commands which are used only in certain modes. These
|
|
commands are usually called "functions". An example is the function
|
|
replace-string, which globally replaces one string with another. When
|
|
you type M-x, Emacs prompts you at the bottom of the screen with
|
|
M-x and you should type the name of the function you wish to call; in
|
|
this case, "replace-string". Just type "repl s<TAB>" and Emacs will
|
|
complete the name. End the command name with <Return>.
|
|
Then type the two "arguments"--the string to be replaced, and the string
|
|
to replace it with--each one ended with a Return.
|
|
|
|
>> Move the cursor to the blank line two lines below this one.
|
|
Then type M-x repl s<Return>changed<Return>altered<Return>.
|
|
|
|
Notice how this line has changed: you've replaced
|
|
the word c-h-a-n-g-e-d with "altered" wherever it occurred
|
|
after the cursor.
|
|
|
|
|
|
* AUTO SAVE
|
|
-----------
|
|
|
|
When you have made changes in a file, but you have not saved them yet,
|
|
they could be lost if your computer crashes. To protect you from
|
|
this, Emacs writes "auto save" files periodically. The auto save file
|
|
name has a # at the beginning and the end; for example, if your file
|
|
is named "hello.c", its auto save file's name is "#hello.c#". When
|
|
you save the file in the normal way, its auto save file is no longer
|
|
necessary so Emacs deletes it.
|
|
|
|
If the computer crashes, you can recover your auto-saved editing by
|
|
finding the file normally (the file you were editing, not the auto
|
|
save file) and then typing M-x recover file<return>. When it asks for
|
|
confirmation, type yes<return> to go ahead and recover the auto-save
|
|
data.
|
|
|
|
|
|
* MODE LINE
|
|
-----------
|
|
|
|
If Emacs sees that you are typing commands slowly it shows them to you
|
|
at the bottom of the screen in an area called the "echo area." The echo
|
|
area contains the bottom line of the screen. The line immediately above
|
|
it is called the MODE LINE. The mode line says something like
|
|
|
|
--**-Emacs: TUTORIAL (Fundamental)--58%----------------------
|
|
|
|
This is a very useful "information" line.
|
|
|
|
You already know what the filename means--it is the file you have
|
|
found. What the --NN%-- means is that NN percent of the file is
|
|
above the top of the screen. If the top of the file is on the screen,
|
|
it will say --Top-- instead of --00%--. If the bottom of the file is
|
|
on the screen, it will say --Bot--. If you are looking at a file so
|
|
small it all fits on the screen, it says --All--.
|
|
|
|
The stars near the front mean that you have made changes to the text.
|
|
Right after you visit or save a file, there are no stars, just dashes.
|
|
|
|
The part of the mode line inside the parentheses is to tell you what
|
|
modes you are in. The default mode is Fundamental which is what you
|
|
are in now. It is an example of a "major mode". There are several
|
|
major modes in Emacs for editing different languages and text, such as
|
|
Lisp mode, Text mode, etc. At any time one and only one major mode is
|
|
active, and its name can always be found in the mode line just where
|
|
"Fundamental" is now. Each major mode makes a few commands behave
|
|
differently. For example, there are commands for creating comments in
|
|
a program, and since each programming language has a different idea of
|
|
what a comment should look like, each major mode has to insert
|
|
comments differently. Each major mode is the name of an extended
|
|
command, which is how you get into the mode. For example,
|
|
M-x fundamental-mode is how to get into Fundamental mode.
|
|
|
|
If you are going to be editing English text, such as this file, you
|
|
should probably use Text Mode.
|
|
>> Type M-x text-mode<Return>.
|
|
|
|
Don't worry, none of the commands you have learned changes Emacs in
|
|
any great way. But you can observe that apostrophes are now part of
|
|
words when you do M-f or M-b. Major modes are usually like that:
|
|
commands don't change into completely unrelated things, but they work
|
|
a little bit differently.
|
|
|
|
To get documentation on your current major mode, type C-h m.
|
|
|
|
>> Use C-u C-v once or more to bring this line near the top of screen.
|
|
>> Type C-h m, to see how Text mode differs from Fundamental mode.
|
|
>> Type C-x 1 to remove the documentation from the screen.
|
|
|
|
Major modes are called major because there are also minor modes.
|
|
They are called minor because they aren't alternatives to the major
|
|
modes, just minor modifications of them. Each minor mode can be
|
|
turned on or off by itself, regardless of what major mode you are in,
|
|
and regardless of the other minor modes. So you can use no minor
|
|
modes, or one minor mode, or any combination of several minor modes.
|
|
|
|
One minor mode which is very useful, especially for editing English
|
|
text, is Auto Fill mode. When this mode is on, Emacs breaks the line
|
|
in between words automatically whenever the line gets too long. You
|
|
can turn this mode on by doing M-x auto-fill-mode<Return>. When the
|
|
mode is on, you can turn it off by doing M-x auto-fill-mode<Return>.
|
|
If the mode is off, this function turns it on, and if the mode is on,
|
|
this function turns it off. This is called "toggling".
|
|
|
|
>> Type M-x auto-fill-mode<Return> now. Then insert a line of "asdf "
|
|
over again until you see it divide into two lines. You must put in
|
|
spaces between them because Auto Fill breaks lines only at spaces.
|
|
|
|
The margin is usually set at 70 characters, but you can change it
|
|
with the C-x f command. You should give the margin setting you want
|
|
as a numeric argument.
|
|
|
|
>> Type C-x f with an argument of 20. (C-u 2 0 C-x f).
|
|
Then type in some text and see Emacs fill lines of 20
|
|
characters with it. Then set the margin back to 70 using
|
|
C-x f again.
|
|
|
|
If you makes changes in the middle of a paragraph, Auto Fill mode
|
|
does not re-fill it for you.
|
|
To re-fill the paragraph, type M-q (Meta-q) with the cursor inside
|
|
that paragraph.
|
|
|
|
>> Move the cursor into the previous paragraph and type M-q.
|
|
|
|
* SEARCHING
|
|
-----------
|
|
|
|
Emacs can do searches for strings (these are groups of contiguous
|
|
characters or words) either forward through the file or backward
|
|
through it. To search for the string means that you are trying to
|
|
locate it somewhere in the file and have Emacs show you where the
|
|
occurrences of the string exist. This type of search is somewhat
|
|
different from what you may be familiar with. It is a search that is
|
|
performed as you type in the thing to search for. The command to
|
|
initiate a search is C-s for forward search, and C-r for reverse
|
|
search. BUT WAIT! Don't do them now. When you type C-s you'll
|
|
notice that the string "I-search" appears as a prompt in the echo
|
|
area. This tells you that Emacs is in what is called an incremental
|
|
search waiting for you to type the thing that you want to search for.
|
|
<RET> terminates a search.
|
|
|
|
>> Now type C-s to start a search. SLOWLY, one letter at a time,
|
|
type the word 'cursor', pausing after you type each
|
|
character to notice what happens to the cursor.
|
|
>> Type C-s to find the next occurrence of "cursor".
|
|
>> Now type <Delete> four times and see how the cursor moves.
|
|
>> Type <RET> to terminate the search.
|
|
|
|
Did you see what happened? Emacs, in an incremental search, tries to
|
|
go to the occurrence of the string that you've typed out so far. To go
|
|
to the next occurrence of 'cursor' just type C-s again. If no such
|
|
occurrence exists Emacs beeps and tells you that it is a failing
|
|
search. C-g would also terminate the search.
|
|
|
|
NOTE: On some systems, typing C-s will freeze the screen and you will
|
|
see no further output from Emacs. This indicates that an operating
|
|
system "feature" called "flow control" is intercepting the C-s and not
|
|
letting it get through to Emacs. To unfreeze the screen, type C-q.
|
|
Then see the section "Spontaneous Entry to Incremental Search" in the
|
|
Emacs manual for advice on dealing with this "feature".
|
|
|
|
If you are in the middle of an incremental search and type <Delete>,
|
|
you'll notice that the last character in the search string is erased
|
|
and the search backs up to the last place of the search. For
|
|
instance, suppose you currently have typed 'cu' and you see that your
|
|
cursor is at the first occurrence of 'cu'. If you now type <Delete>,
|
|
the 'u' on the search line is erased and you'll be repositioned in the
|
|
text to the occurrence of 'c' where the search took you before you
|
|
typed the 'u'. This provides a useful means for backing up while you
|
|
are searching.
|
|
|
|
If you are in the middle of a search and type a control or meta
|
|
character (with a few exceptions--characters that are special in
|
|
a search, such as C-s and C-r), the search is terminated.
|
|
|
|
The C-s starts a search that looks for any occurrence of the search
|
|
string AFTER the current cursor position. But what if you want to
|
|
search for something earlier in the text? To do this, type C-r for
|
|
Reverse search. Everything that applies to C-s applies to C-r except
|
|
that the direction of the search is reversed.
|
|
|
|
|
|
* MULTIPLE WINDOWS
|
|
------------------
|
|
|
|
One of the nice features of Emacs is that you can display more than one
|
|
window on the screen at the same time.
|
|
|
|
>> Move the cursor to this line and type C-u 0 C-l.
|
|
|
|
>> Now type C-x 2 which splits the screen into two windows.
|
|
Both windows display this tutorial. The cursor stays in the top window.
|
|
|
|
>> Type C-M-v to scroll the bottom window.
|
|
(If you don't have a real Meta key, type ESC C-v.)
|
|
|
|
>> Type C-x o ("o" for "other") to move the cursor to the bottom window.
|
|
>> Use C-v and M-v in the bottom window to scroll it.
|
|
Keep reading these directions in the top window.
|
|
|
|
>> Type C-x o again to move the cursor back to the top window.
|
|
The cursor is still just where it was in the top window before.
|
|
|
|
You can keep using C-x o to switch between the windows. Each
|
|
window has its own cursor position, but only one window actually
|
|
shows the cursor. All the ordinary editing commands apply to the
|
|
window that the cursor is in.
|
|
|
|
The command C-M-v is very useful when you are editing text in one
|
|
window and using the other window just for reference. You can keep
|
|
the cursor always in the window where you are editing, and edit
|
|
there as you advance through the other window.
|
|
|
|
C-M-v is an example of a CONTROL-META character. If you have a real
|
|
META key, you can type C-M-v by holding down both CTRL and META while
|
|
typing v.
|
|
|
|
It doesn't matter whether CTRL or META "comes first," because both of
|
|
these keys act by modifying the characters you type. But if you don't
|
|
have a real META key, and you use ESC instead, the order does matter:
|
|
you must type ESC followed by CTRL-v; CTRL-ESC v will not work. This
|
|
is because ESC is a character in its own right, not a modifier key.
|
|
|
|
>> Type C-x 1 (in the top window) to get rid of the bottom window.
|
|
|
|
(If you had typed C-x 1 in the bottom window, that would get rid
|
|
of the top one. Think of this command as "Keep just one
|
|
window--the window I am already in.")
|
|
|
|
You don't have to display the same buffer in both windows. If
|
|
you use C-x C-f to find a file in one window, the other window
|
|
doesn't change. You can pick a file in each window
|
|
independently.
|
|
|
|
Here is another way to use two windows to display two different
|
|
things:
|
|
|
|
>> Type C-x 4 C-f followed by the name of one of your files.
|
|
End with <RETURN>. See the specified file appear in the bottom
|
|
window. The cursor goes there, too.
|
|
|
|
>> Type C-x o to go back to the top window, and C-x 1 to delete
|
|
the bottom window.
|
|
|
|
|
|
* RECURSIVE EDITING LEVELS
|
|
--------------------------
|
|
|
|
Sometimes you will get into what is called a "recursive editing
|
|
level". This is indicated by square brackets in the mode line,
|
|
surrounding the parentheses around the major mode name. For
|
|
example, you might see [(Fundamental)] instead of (Fundamental).
|
|
|
|
To get out of the recursive editing level, type ESC ESC ESC. That is
|
|
an all-purpose "get out" command. You can also use it for eliminating
|
|
extra windows, and getting out of the minibuffer.
|
|
|
|
>> Type M-x to get into a minibuffer; then type ESC ESC ESC to get out.
|
|
|
|
You can't use C-g to get out of a recursive editing level because C-g
|
|
is used for canceling commands and arguments WITHIN the recursive
|
|
editing level.
|
|
|
|
|
|
* GETTING MORE HELP
|
|
-------------------
|
|
|
|
In this tutorial we have tried to supply just enough information to
|
|
get you started using Emacs. There is so much available in Emacs that
|
|
it would be impossible to explain it all here. However, you may want
|
|
to learn more about Emacs since it has numerous desirable features
|
|
that you don't know about yet. Emacs has a great deal of internal
|
|
documentation. All of these commands can be accessed through
|
|
the character Control-h, which we call "the Help character"
|
|
because of the function it serves.
|
|
|
|
To use the HELP features, type the C-h character, and then a
|
|
character saying what kind of help you want. If you are REALLY lost,
|
|
type C-h ? and Emacs will tell you what kinds of help it can give.
|
|
If you have typed C-h and decide you don't want any help, just
|
|
type C-g to cancel it.
|
|
|
|
(Some sites rebind the character C-h. They really shouldn't do this
|
|
as a blanket measure, so complain to the operator. Meanwhile, if C-h
|
|
does not display a message about help at the bottom of the screen, try
|
|
typing M-x help RET instead.)
|
|
|
|
The most basic HELP feature is C-h c. Type C-h, a c, and a
|
|
command character or sequence, and Emacs displays a very brief
|
|
description of the command.
|
|
|
|
>> Type C-h c Control-p.
|
|
The message should be something like
|
|
|
|
C-p runs the command previous-line
|
|
|
|
This tells you the "name of the function". That is important in
|
|
writing Lisp code to extend Emacs; it also is enough to remind
|
|
you of what the command does if you have seen it before but did
|
|
not remember.
|
|
|
|
Multi-character commands such as C-x C-s and (if you have no META or
|
|
EDIT key) <ESC>v are also allowed after C-h c.
|
|
|
|
To get more information on the command, use C-h k instead of C-h c.
|
|
|
|
>> Type C-h k Control-p.
|
|
|
|
This displays the documentation of the function, as well as its
|
|
name, in an Emacs window. When you are finished reading the
|
|
output, type C-x 1 to get rid of the help text. You do not have
|
|
to do this right away. You can do some editing while referring
|
|
to the help text and then type C-x 1.
|
|
|
|
Here are some other useful C-h options:
|
|
|
|
C-h f Describe a function. You type in the name of the
|
|
function.
|
|
|
|
>> Try typing C-h f previous-line<Return>.
|
|
This prints all the information Emacs has about the
|
|
function which implements the C-p command.
|
|
|
|
C-h a Command Apropos. Type in a keyword and Emacs will list
|
|
all the commands whose names contain that keyword.
|
|
These commands can all be invoked with Meta-x.
|
|
For some commands, Command Apropos will also list a one
|
|
or two character sequence which has the same effect.
|
|
|
|
>> Type C-h a file<Return>.
|
|
|
|
This displays in another window a list of all M-x commands with
|
|
"file" in their names. You will also see commands like C-x C-f
|
|
and C-x C-w, listed beside the command names find-file and
|
|
write-file.
|
|
|
|
>> Type C-M-v to scroll the help window. Do this a few times.
|
|
|
|
>> Type C-x 1 to delete the help window.
|
|
|
|
|
|
* CONCLUSION
|
|
------------
|
|
|
|
Remember, to exit Emacs permanently use C-x C-c. To exit to a shell
|
|
temporarily, so that you can come back in, use C-z.
|
|
|
|
This tutorial is meant to be understandable to all new users, so if
|
|
you found something unclear, don't sit and blame yourself - complain!
|
|
|
|
|
|
COPYING
|
|
-------
|
|
|
|
This tutorial descends from a long line of Emacs tutorials
|
|
starting with the one written by Stuart Cracraft for the original Emacs.
|
|
|
|
This version of the tutorial, like GNU Emacs, is copyrighted, and
|
|
comes with permission to distribute copies on certain conditions:
|
|
|
|
Copyright (c) 1985 Free Software Foundation
|
|
|
|
Permission is granted to anyone to make or distribute verbatim copies
|
|
of this document as received, in any medium, provided that the
|
|
copyright notice and permission notice are preserved,
|
|
and that the distributor grants the recipient permission
|
|
for further redistribution as permitted by this notice.
|
|
|
|
Permission is granted to distribute modified versions
|
|
of this document, or of portions of it,
|
|
under the above conditions, provided also that they
|
|
carry prominent notices stating who last altered them.
|
|
|
|
The conditions for copying Emacs itself are slightly different
|
|
but in the same spirit. Please read the file COPYING and then
|
|
do give copies of GNU Emacs to your friends.
|
|
Help stamp out software obstructionism ("ownership") by using,
|
|
writing, and sharing free software!
|