7. Exiting Emacs

There are two commands for exiting Emacs, and three kinds of exiting: iconifying Emacs, suspending Emacs, and killing Emacs.

Iconifying means replacing the Emacs frame with a small box or “icon” on the screen. This is the usual way to exit Emacs when you're using a graphical display—if you bother to “exit” at all. (Just switching to another application is usually sufficient.)

Suspending means stopping Emacs temporarily and returning control to its parent process (usually a shell), allowing you to resume editing later in the same Emacs job. This is the usual way to exit Emacs when running it on a text terminal.

Killing Emacs means destroying the Emacs job. You can run Emacs again later, but you will get a fresh Emacs; there is no way to resume the same editing session after it has been killed.

C-z

Suspend Emacs (suspend-emacs) or iconify a frame (iconify-or-deiconify-frame).

C-x C-c

Kill Emacs (save-buffers-kill-emacs).

On graphical displays, C-z runs the command iconify-or-deiconify-frame, which temporarily iconifies (or “minimizes”) the selected Emacs frame (see section Frames and Graphical Displays). You can then use the window manager to select some other application. (You could select another application without iconifying Emacs first, but getting the Emacs frame out of the way can make it more convenient to find the other application.)

On a text terminal, C-z runs the command suspend-emacs. Suspending Emacs takes you back to the shell from which you invoked Emacs. You can resume Emacs with the shell command %emacs in most common shells. On systems that don't support suspending programs, C-z starts an inferior shell that communicates directly with the terminal, and Emacs waits until you exit the subshell. (The way to do that is probably with C-d or exit, but it depends on which shell you use.) On these systems, you can only get back to the shell from which Emacs was run (to log out, for example) when you kill Emacs.

Suspending can fail if you run Emacs under a shell that doesn't support suspendion of its subjobs, even if the system itself does support it. In such a case, you can set the variable cannot-suspend to a non-nil value to force C-z to start an inferior shell.

To exit and kill Emacs, type C-x C-c (save-buffers-kill-emacs). A two-character key is used to make it harder to type by accident. This command first offers to save any modified file-visiting buffers. If you do not save them all, it asks for confirmation with yes before killing Emacs, since any changes not saved now will be lost forever. Also, if any subprocesses are still running, C-x C-c asks for confirmation about them, since killing Emacs will also kill the subprocesses.

If the value of the variable confirm-kill-emacs is non-nil, C-x C-c assumes that its value is a predicate function, and calls that function. If the result is non-nil, the session is killed, otherwise Emacs continues to run. One convenient function to use as the value of confirm-kill-emacs is the function yes-or-no-p. The default value of confirm-kill-emacs is nil.

You can't resume an Emacs session after killing it. Emacs can, however, record certain session information when you kill it, such as which files you visited, so the next time you start Emacs it will try to visit the same files. See section Saving Emacs Sessions.

The operating system usually listens for certain special characters whose meaning is to kill or suspend the program you are running. This operating system feature is turned off while you are in Emacs. The meanings of C-z and C-x C-c as keys in Emacs were inspired by the use of C-z and C-c on several operating systems as the characters for stopping or killing a program, but that is their only relationship with the operating system. You can customize these keys to run any commands of your choice (see section Keymaps).