Next: Indirect Buffers, Previous: Creating Buffers, Up: Buffers [Contents][Index]
Killing a buffer makes its name unknown to Emacs and makes the memory space it occupied available for other use.
The buffer object for the buffer that has been killed remains in
existence as long as anything refers to it, but it is specially marked
so that you cannot make it current or display it. Killed buffers retain
their identity, however; if you kill two distinct buffers, they remain
distinct according to eq although both are dead.
If you kill a buffer that is current or displayed in a window, Emacs automatically selects or displays some other buffer instead. This means that killing a buffer can change the current buffer. Therefore, when you kill a buffer, you should also take the precautions associated with changing the current buffer (unless you happen to know that the buffer being killed isn’t current). See Current Buffer.
If you kill a buffer that is the base buffer of one or more indirect buffers (see Indirect Buffers), the indirect buffers are automatically killed as well.
The buffer-name of a buffer is nil if, and only if,
the buffer is killed. A buffer that has not been killed is called a
live buffer. To test whether a buffer is live or killed, use
the function buffer-live-p (see below).
This function kills the buffer buffer-or-name, freeing all its
memory for other uses or to be returned to the operating system. If
buffer-or-name is nil or omitted, it kills the current
buffer.
Any processes that have this buffer as the process-buffer are
sent the SIGHUP (“hangup”) signal, which normally causes them
to terminate. See Signals to Processes.
If the buffer is visiting a file and contains unsaved changes,
kill-buffer asks the user to confirm before the buffer is killed.
It does this even if not called interactively. To prevent the request
for confirmation, clear the modified flag before calling
kill-buffer. See Buffer Modification.
This function calls replace-buffer-in-windows for cleaning up
all windows currently displaying the buffer to be killed.
Killing a buffer that is already dead has no effect.
This function returns t if it actually killed the buffer. It
returns nil if the user refuses to confirm or if
buffer-or-name was already dead.
(kill-buffer "foo.unchanged")
⇒ t
(kill-buffer "foo.changed")
---------- Buffer: Minibuffer ----------
Buffer foo.changed modified; kill anyway? (yes or no) yes
---------- Buffer: Minibuffer ----------
⇒ t
Before confirming unsaved changes, kill-buffer calls the functions
in the list kill-buffer-query-functions, in order of appearance,
with no arguments. The buffer being killed is the current buffer when
they are called. The idea of this feature is that these functions will
ask for confirmation from the user. If any of them returns nil,
kill-buffer spares the buffer’s life.
This is a normal hook run by kill-buffer after asking all the
questions it is going to ask, just before actually killing the buffer.
The buffer to be killed is current when the hook functions run.
See Hooks. This variable is a permanent local, so its local binding
is not cleared by changing major modes.
This variable, if non-nil in a particular buffer, tells
save-buffers-kill-emacs and save-some-buffers (if the
second optional argument to that function is t) to offer to
save that buffer, just as they offer to save file-visiting buffers.
See Definition of save-some-buffers. The variable
buffer-offer-save automatically becomes buffer-local when set
for any reason. See Buffer-Local Variables.
This variable, if non-nil in a particular buffer, tells
save-buffers-kill-emacs and save-some-buffers to save
this buffer (if it’s modified) without asking the user. The variable
automatically becomes buffer-local when set for any reason.
This function returns t if object is a live buffer (a
buffer which has not been killed), nil otherwise.
Next: Indirect Buffers, Previous: Creating Buffers, Up: Buffers [Contents][Index]