Commit | Line | Data |
---|---|---|
6bf7aab6 DL |
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 | |
6 | @cindex entering Emacs | |
7 | @cindex starting Emacs | |
8 | ||
60a96371 | 9 | The usual way to invoke Emacs is with the shell command @command{emacs}. |
6bf7aab6 DL |
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. | |
15 | ||
16 | If you run Emacs from a shell window under the X Window System, run it | |
60a96371 | 17 | in the background with @command{emacs&}. This way, Emacs does not tie up |
6bf7aab6 DL |
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. | |
21 | ||
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}.) | |
29 | ||
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 | |
34 | editors. | |
35 | ||
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. | |
41 | ||
42 | But starting a new Emacs each time you want to edit a different file | |
291ff57c RS |
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. | |
6bf7aab6 DL |
48 | |
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 | |
55 | file. | |
56 | ||
57 | @node Exiting, Basic, Entering Emacs, Top | |
58 | @section Exiting Emacs | |
59 | @cindex exiting | |
60 | @cindex killing Emacs | |
61 | @cindex suspending | |
62 | @cindex leaving Emacs | |
63 | @cindex quitting Emacs | |
64 | ||
65 | There are two commands for exiting Emacs because there are two kinds | |
66 | of exiting: @dfn{suspending} Emacs and @dfn{killing} Emacs. | |
67 | ||
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. | |
72 | ||
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. | |
76 | ||
77 | @table @kbd | |
78 | @item C-z | |
79 | Suspend Emacs (@code{suspend-emacs}) or iconify a frame | |
80 | (@code{iconify-or-deiconify-frame}). | |
81 | @item C-x C-c | |
82 | Kill Emacs (@code{save-buffers-kill-emacs}). | |
83 | @end table | |
84 | ||
85 | @kindex C-z | |
86 | @findex suspend-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 | |
60a96371 | 89 | Emacs with the shell command @command{%emacs} in most common shells. |
6bf7aab6 DL |
90 | |
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 | |
60a96371 | 94 | probably with @kbd{C-d} or @command{exit}, but it depends on which shell |
6bf7aab6 DL |
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. | |
97 | ||
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.) | |
104 | ||
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 | |
015a26d7 | 107 | application that uses its own X windows is not meaningful or useful. |
6bf7aab6 DL |
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. | |
111 | ||
112 | @kindex C-x C-c | |
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 | |
121 | immediately. | |
122 | ||
e020c833 EZ |
123 | @vindex confirm-kill-emacs |
124 | If the value of the variable @code{confirm-kill-emacs} is | |
125 | non-@code{nil}, @kbd{C-x C-c} assumes that its value is a predicate | |
126 | function, and calls that function. If the result is non-@code{nil}, the | |
127 | session is killed, otherwise Emacs continues to run. One convenient | |
128 | function to use as the value of @code{confirm-kill-emacs} is the | |
129 | function @code{yes-or-no-p}. The default value of | |
130 | @code{confirm-kill-emacs} is @code{nil}. | |
131 | ||
6bf7aab6 DL |
132 | There is no way to restart an Emacs session once you have killed it. |
133 | You can, however, arrange for Emacs to record certain session | |
134 | information, such as which files are visited, when you kill it, so that | |
135 | the next time you restart Emacs it will try to visit the same files and | |
136 | so on. @xref{Saving Emacs Sessions}. | |
137 | ||
138 | The operating system usually listens for certain special characters | |
139 | whose meaning is to kill or suspend the program you are running. | |
140 | @b{This operating system feature is turned off while you are in Emacs.} | |
141 | The meanings of @kbd{C-z} and @kbd{C-x C-c} as keys in Emacs were | |
142 | inspired by the use of @kbd{C-z} and @kbd{C-c} on several operating | |
143 | systems as the characters for stopping or killing a program, but that is | |
144 | their only relationship with the operating system. You can customize | |
145 | these keys to run any commands of your choice (@pxref{Keymaps}). |