Either quit or abort, whichever makes sense (@code{keyboard-escape-quit}).
@item M-x top-level
Abort all recursive editing levels that are currently executing.
-@item C-x u
+@item C-/
+@itemx C-x u
+@itemx C-_
Cancel a previously made change in the buffer contents (@code{undo}).
@end table
ordinary key and has its meaning only because of its binding in the
keymap. @xref{Recursive Edit}.
- @kbd{C-x u} (@code{undo}) is not strictly speaking a way of canceling
+ @kbd{C-/} (@code{undo}) is not strictly speaking a way of canceling
a command, but you can think of it as canceling a command that already
-finished executing. @xref{Undo}, for more information
-about the undo facility.
+finished executing. @xref{Undo}, for more information about the undo
+facility.
@node Lossage, Bugs, Quitting, Top
@section Dealing with Emacs Trouble
@cindex @key{BACKSPACE} vs @key{DEL}
@cindex usual erasure key
- Every keyboard has a large key, a little ways above the @key{RET} or
-@key{ENTER} key, which you normally use outside Emacs to erase the
-last character that you typed. We call this key @dfn{the usual
-erasure key}. In Emacs, it is supposed to be equivalent to @key{DEL},
-and when Emacs is properly configured for your terminal, it translates
-that key into the character @key{DEL}.
+ Every keyboard has a large key, usually labelled @key{Backspace},
+which is ordinarily used to erase the last character that you typed.
+We call this key @dfn{the usual erasure key}. In Emacs, it is
+supposed to be equivalent to @key{DEL}.
When Emacs starts up on a graphical display, it determines
-automatically which key should be @key{DEL}. In some unusual cases
+automatically which key should be @key{DEL}. In some unusual cases,
Emacs gets the wrong information from the system. If the usual
erasure key deletes forwards instead of backwards, that is probably
-what happened---Emacs ought to be treating the @key{DELETE} key as
+what happened---Emacs ought to be treating the @key{Backspace} key as
@key{DEL}, but it isn't.
- On a graphical display, if the usual erasure key is labeled
-@key{BACKSPACE} and there is a @key{DELETE} key elsewhere, but the
-@key{DELETE} key deletes backward instead of forward, that too
+ Some keyboards also have a @key{Delete} key, which is ordinarily
+used to forwards. If this key deletes backward in Emacs, that too
suggests Emacs got the wrong information---but in the opposite sense.
-It ought to be treating the @key{BACKSPACE} key as @key{DEL}, and
-treating @key{DELETE} differently, but it isn't.
On a text-only terminal, if you find the usual erasure key prompts
for a Help command, like @kbd{Control-h}, instead of deleting a
@findex normal-erase-is-backspace-mode
To fix the problem automatically for every Emacs session, you can
put one of the following lines into your @file{.emacs} file
-(@pxref{Init File}). For the first case above, where @key{DELETE}
+(@pxref{Init File}). For the first case above, where @key{Backspace}
deletes forwards instead of backwards, use this line to make
-@key{DELETE} act as @key{DEL} (resulting in behavior compatible
+@key{Backspace} act as @key{DEL} (resulting in behavior compatible
with Emacs 20 and previous versions):
@lisp
@end lisp
@noindent
-For the other two cases, where @key{BACKSPACE} ought to act as
-@key{DEL}, use this line:
+For the other two cases, use this line:
@lisp
(normal-erase-is-backspace-mode 1)
@key{DEL}, and @code{nil} specifies the other mode. @xref{Easy
Customization}.
- On a graphical display, it can also happen that the usual erasure key
-is labeled @key{BACKSPACE}, there is a @key{DELETE} key elsewhere, and
-both keys delete forward. This probably means that someone has
-redefined your @key{BACKSPACE} key as a @key{DELETE} key. With X,
-this is typically done with a command to the @code{xmodmap} program
-when you start the server or log in. The most likely motive for this
-customization was to support old versions of Emacs, so we recommend
-you simply remove it now.
-
@node Stuck Recursive
@subsection Recursive Editing Levels