bug#25209: 25.1; can't delete *Shell Command Output*

[Andreas Schwab <schwab@linux-m68k.org>]

On Dez 19 2016, Andreas Schwab <schwab@linux-m68k.org> wrote:

> On Dez 15 2016, Francesco Potortì <pot@gnu.org> wrote:
>
>> On a long-running multi-tty Emacs, at one point the *Shell Command
>> Output* buffer refuses to go away.
>>
>> If I try to kill it, nothing happens, whether the current buffer is that
>> one or any other one.  The contents of the *Shell Command Output* buffer
>> are always visible in the minibuffer.  So, to make it unobtrusive, I
>> need to issue an
>>  M-! echo -n RET
>> every time the *Shell Command Output* buffer is dirtied.
>
> Did you perhaps quit while the output of a shell-command was being
> displayed, because it took too long?  In that situation Emacs can end up
> in a state where (minibuffer-window) points to the *Shell Command
> Output* buffer, and kill-buffer will refuse to kill the buffer.

I think the problem is that vertical-motion (as called by
display-message-or-buffer via count-screen-lines) is not properly
protecting against quit when it temporarily modifies the window's
buffer.

Andreas.

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Andreas Schwab, schwab@linux-m68k.org
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