elisp: Killing Emacs
38.2.1 Killing Emacs
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Killing Emacs means ending the execution of the Emacs process. If you
started Emacs from a terminal, the parent process normally resumes
control. The low-level primitive for killing Emacs is ‘kill-emacs’.
-- Command: kill-emacs &optional exit-data
This command calls the hook ‘kill-emacs-hook’, then exits the Emacs
process and kills it.
If EXIT-DATA is an integer, that is used as the exit status of the
Emacs process. (This is useful primarily in batch operation; see
Batch Mode.)
If EXIT-DATA is a string, its contents are stuffed into the
terminal input buffer so that the shell (or whatever program next
reads input) can read them.
The ‘kill-emacs’ function is normally called via the higher-level
command ‘C-x C-c’ (‘save-buffers-kill-terminal’).
(emacs)Exiting. It is also called automatically if Emacs receives a
‘SIGTERM’ or ‘SIGHUP’ operating system signal (e.g., when the
controlling terminal is disconnected), or if it receives a ‘SIGINT’
signal while running in batch mode (Batch Mode).
-- Variable: kill-emacs-hook
This normal hook is run by ‘kill-emacs’, before it kills Emacs.
Because ‘kill-emacs’ can be called in situations where user
interaction is impossible (e.g., when the terminal is
disconnected), functions on this hook should not attempt to
interact with the user. If you want to interact with the user when
Emacs is shutting down, use ‘kill-emacs-query-functions’, described
below.
When Emacs is killed, all the information in the Emacs process, aside
from files that have been saved, is lost. Because killing Emacs
inadvertently can lose a lot of work, the ‘save-buffers-kill-terminal’
command queries for confirmation if you have buffers that need saving or
subprocesses that are running. It also runs the abnormal hook
‘kill-emacs-query-functions’:
-- Variable: kill-emacs-query-functions
When ‘save-buffers-kill-terminal’ is killing Emacs, it calls the
functions in this hook, after asking the standard questions and
before calling ‘kill-emacs’. The functions are called in order of
appearance, with no arguments. Each function can ask for
additional confirmation from the user. If any of them returns
‘nil’, ‘save-buffers-kill-emacs’ does not kill Emacs, and does not
run the remaining functions in this hook. Calling ‘kill-emacs’
directly does not run this hook.
Info Catalog
elisp: Getting Out
elisp: Suspending Emacs