Re: [Crash-utility] The "ctrl + c" doesn't work in crash
Hi Dave,
-----Original Message-----
From: crash-utility-bounces(a)redhat.com
[mailto:crash-utility-bounces@redhat.com] On Behalf Of Dave Anderson
Sent: Thursday, March 15, 2012 9:31 PM
To: Discussion list for crash utility usage, maintenance and development
Subject: Re: [Crash-utility] The "ctrl + c" doesn't work in crash
----- Original Message -----
> Hi Dave,
>
> I found the "ctrl + c" doesn't work well in crash. Sometimes, we may
> type a wrong command and want to directly cancel it by "ctrl+c" like
> in the bash. But this combination only do seldom response, what I
> mean is I once see it works once or twice.
>
> I also notice there was a mail thread talking about it:
> http://www.redhat.com/archives/crash-utility/2009-October/msg00006.html
>
> But on the most new crash 6.0.4, simply ctrl+c three times or more
> would not lead to a new prompt...
SIGINT's are always caught, and it depends upon whether the command is
currently being fed into the scroller, and in some cases, the command
itself. See the callers of received_SIGINT() for example.
I see...
And while I redo the test, I can see SIGINT work again, prompt the input > when type
three ctrl+c. No idea why previous ctrl+c not working...
I still get a another display issue regarding the ctrl+c.
I use the "log" command to show the kernel dmesg, and always the message buffer
is large which cannot be displayed in one screen. So I could see the below notice in the
foot of the screen:
-- MORE -- forward: <SPACE>, <ENTER> or j backward: b or k quit: q
If I type "ctrl+c" when the message still not get fully displayed, eventually I
would see the previous only one foot notice would show up several and keep growing.
Like this:
[ 413.741638] Unable to handle kernel NULL pointer dereference at virtual address
00000000
[ 413.749725] pgd = d3e90000
[ 413.752441] [00000000] *pgd=12109831, *pte=00000000, *ppte=00000000
-- MORE -- forward: <SPACE>, <ENTER> or j backward: b or k quit: q
-- MORE -- forward: <SPACE>, <ENTER> or j backward: b or k quit: q
-- MORE -- forward: <SPACE>, <ENTER> or j backward: b or k quit: q
And when this abnormal happens, the <space> would be displayed normally as before,
but when the whole message is drained out, the console prompt would not be displayed. And
each <enter> after this abnormal, would lead to another such notice to be showed up
like the message buffer itself.
So is it a bug for the cmdline handling?
Dave
Thanks,
Lei