27.10 Killing Buffers

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 in general 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). Voir la section The Current Buffer.

If you kill a buffer that is the base buffer of one or more indirect buffers, the indirect buffers are automatically killed as well.

The buffer-name of a killed buffer is nil. You can use this feature to test whether a buffer has been killed:

(defun buffer-killed-p (buffer)
  "Return t if BUFFER is killed."
  (not (buffer-name buffer)))

Command: kill-buffer buffer-or-name

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, it kills the current buffer.

Any processes that have this buffer as the process-buffer are sent the SIGHUP signal, which normally causes them to terminate. (The basic meaning of SIGHUP is that a dialup line has been disconnected.) Voir la section Sending 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. Voir la section Buffer Modification.

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

Variable: kill-buffer-query-functions

After 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.

Variable: kill-buffer-hook

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. Voir la section Hooks. This variable is a permanent local, so its local binding is not cleared by changing major modes.

Variable: buffer-offer-save

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. Voir Definition of save-some-buffers. The variable buffer-offer-save automatically becomes buffer-local when set for any reason. Voir la section Buffer-Local Variables.

Variable: buffer-save-without-query

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.

Function: buffer-live-p object

This function returns t if object is a buffer which has not been killed, nil otherwise.

Ce document a été généré par Eric Reinbold le 13 Octobre 2007 en utilisant texi2html 1.78.