* doc/emacs/misc.texi (Single Shell): Mention async-shell-command-buffer.

* etc/NEWS: Related markup.

doc/emacs/ChangeLog

+2012-11-12  Glenn Morris  <rgm@gnu.org>
+
+	* misc.texi (Single Shell): Mention async-shell-command-buffer.
+
 2012-11-10  Glenn Morris  <rgm@gnu.org>
 
 	* misc.texi (Terminal emulator): Rename `term-face' to `term'.

doc/emacs/misc.texi

@@ -542,11 +542,19 @@ which is impossible to ignore.
 You can also type @kbd{M-&} (@code{async-shell-command}) to execute a
 shell command asynchronously; this is exactly like calling @kbd{M-!}
 with a trailing @samp{&}, except that you do not need the @samp{&}.
-The output buffer for asynchronous shell commands is named
+The default output buffer for asynchronous shell commands is named
 @samp{*Async Shell Command*}.  Emacs inserts the output into this
 buffer as it comes in, whether or not the buffer is visible in a
 window.
 
+@vindex async-shell-command-buffer
+  If you want to run more than one asynchronous shell command at the
+same time, they could end up competing for the output buffer.  The
+option @code{async-shell-command-buffer} specifies what to do about
+this; e.g., whether to rename the pre-existing output buffer, or to
+use a different buffer for the new command.  Consult the variable's
+documentation for more possibilities.
+
 @kindex M-|
 @findex shell-command-on-region
   @kbd{M-|} (@code{shell-command-on-region}) is like @kbd{M-!}, but

etc/NEWS

@@ -561,8 +561,9 @@ Sphinx support has been improved.
 
 *** `sh-use-smie' lets you choose a new indentation and navigation code.
 
++++
 ** New option `async-shell-command-buffer' specifies the buffer to use
-for a new asynchronous shell command when the default output buffer
+for a new asynchronous `shell-command' when the default output buffer
 `*Async Shell Command*' is already in use.
 
 ---