1 @c This is part of the Emacs manual.
2 @c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995 Free Software Foundation, Inc.
3 @c See file emacs.texi for copying conditions.
4 @node Entering Emacs, Exiting, Text Characters, Top
5 @chapter Entering and Exiting Emacs
9 The usual way to invoke Emacs is with the shell command @command{emacs}.
10 Emacs clears the screen and then displays an initial help message and
11 copyright notice. Some operating systems discard all type-ahead when
12 Emacs starts up; they give Emacs no way to prevent this. Therefore, it
13 is advisable to wait until Emacs clears the screen before typing your
14 first editing command.
16 If you run Emacs from a shell window under the X Window System, run it
17 in the background with @command{emacs&}. This way, Emacs does not tie up
18 the shell window, so you can use that to run other shell commands while
19 Emacs operates its own X windows. You can begin typing Emacs commands
20 as soon as you direct your keyboard input to the Emacs frame.
22 @vindex initial-major-mode
23 When Emacs starts up, it makes a buffer named @samp{*scratch*}.
24 That's the buffer you start out in. The @samp{*scratch*} buffer uses Lisp
25 Interaction mode; you can use it to type Lisp expressions and evaluate
26 them, or you can ignore that capability and simply doodle. (You can
27 specify a different major mode for this buffer by setting the variable
28 @code{initial-major-mode} in your init file. @xref{Init File}.)
30 It is possible to specify files to be visited, Lisp files to be
31 loaded, and functions to be called, by giving Emacs arguments in the
32 shell command line. @xref{Command Arguments}. But we don't recommend
33 doing this. The feature exists mainly for compatibility with other
36 Many other editors are designed to be started afresh each time you
37 want to edit. You edit one file and then exit the editor. The next
38 time you want to edit either another file or the same one, you must run
39 the editor again. With these editors, it makes sense to use a
40 command-line argument to say which file to edit.
42 But starting a new Emacs each time you want to edit a different file
43 does not make sense. For one thing, this would be annoyingly slow.
44 For another, this would fail to take advantage of Emacs's ability to
45 visit more than one file in a single editing session. And it would
46 lose the other accumulated context, such as the kill ring, registers,
47 undo history, and mark ring.
49 The recommended way to use GNU Emacs is to start it only once, just
50 after you log in, and do all your editing in the same Emacs session.
51 Each time you want to edit a different file, you visit it with the
52 existing Emacs, which eventually comes to have many files in it ready
53 for editing. Usually you do not kill the Emacs until you are about to
54 log out. @xref{Files}, for more information on visiting more than one
57 @node Exiting, Basic, Entering Emacs, Top
58 @section Exiting Emacs
63 @cindex quitting Emacs
65 There are two commands for exiting Emacs because there are two kinds
66 of exiting: @dfn{suspending} Emacs and @dfn{killing} Emacs.
68 @dfn{Suspending} means stopping Emacs temporarily and returning
69 control to its parent process (usually a shell), allowing you to resume
70 editing later in the same Emacs job, with the same buffers, same kill
71 ring, same undo history, and so on. This is the usual way to exit.
73 @dfn{Killing} Emacs means destroying the Emacs job. You can run Emacs
74 again later, but you will get a fresh Emacs; there is no way to resume
75 the same editing session after it has been killed.
79 Suspend Emacs (@code{suspend-emacs}) or iconify a frame
80 (@code{iconify-or-deiconify-frame}).
82 Kill Emacs (@code{save-buffers-kill-emacs}).
87 To suspend Emacs, type @kbd{C-z} (@code{suspend-emacs}). This takes
88 you back to the shell from which you invoked Emacs. You can resume
89 Emacs with the shell command @command{%emacs} in most common shells.
91 On systems that do not support suspending programs, @kbd{C-z} starts
92 an inferior shell that communicates directly with the terminal.
93 Emacs waits until you exit the subshell. (The way to do that is
94 probably with @kbd{C-d} or @command{exit}, but it depends on which shell
95 you use.) The only way on these systems to get back to the shell from
96 which Emacs was run (to log out, for example) is to kill Emacs.
98 Suspending also fails if you run Emacs under a shell that doesn't
99 support suspending programs, even if the system itself does support it.
100 In such a case, you can set the variable @code{cannot-suspend} to a
101 non-@code{nil} value to force @kbd{C-z} to start an inferior shell.
102 (One might also describe Emacs's parent shell as ``inferior'' for
103 failing to support job control properly, but that is a matter of taste.)
105 When Emacs communicates directly with an X server and creates its own
106 dedicated X windows, @kbd{C-z} has a different meaning. Suspending an
107 application that uses its own X windows is not meaningful or useful.
108 Instead, @kbd{C-z} runs the command @code{iconify-or-deiconify-frame},
109 which temporarily closes up the selected Emacs frame (@pxref{Frames}).
110 The way to get back to a shell window is with the window manager.
113 @findex save-buffers-kill-emacs
114 To kill Emacs, type @kbd{C-x C-c} (@code{save-buffers-kill-emacs}). A
115 two-character key is used for this to make it harder to type. This
116 command first offers to save any modified file-visiting buffers. If you
117 do not save them all, it asks for reconfirmation with @kbd{yes} before
118 killing Emacs, since any changes not saved will be lost forever. Also,
119 if any subprocesses are still running, @kbd{C-x C-c} asks for
120 confirmation about them, since killing Emacs will kill the subprocesses
123 There is no way to restart an Emacs session once you have killed it.
124 You can, however, arrange for Emacs to record certain session
125 information, such as which files are visited, when you kill it, so that
126 the next time you restart Emacs it will try to visit the same files and
127 so on. @xref{Saving Emacs Sessions}.
129 The operating system usually listens for certain special characters
130 whose meaning is to kill or suspend the program you are running.
131 @b{This operating system feature is turned off while you are in Emacs.}
132 The meanings of @kbd{C-z} and @kbd{C-x C-c} as keys in Emacs were
133 inspired by the use of @kbd{C-z} and @kbd{C-c} on several operating
134 systems as the characters for stopping or killing a program, but that is
135 their only relationship with the operating system. You can customize
136 these keys to run any commands of your choice (@pxref{Keymaps}).