This is the mail archive of the
cygwin
mailing list for the Cygwin project.
Re: GDB Ctrl-C Interrupt Fails WORKAROUND
- From: Christopher Faylor <cgf-use-the-mailinglist-please at cygwin dot com>
- To: cygwin at cygwin dot com
- Date: Wed, 28 Feb 2007 21:58:39 -0500
- Subject: Re: GDB Ctrl-C Interrupt Fails WORKAROUND
- References: <E5AED0BA-EE62-4D97-96CE-8A96D0C0F559@qualcomm.com> <37FD7E0C-3F61-4EB2-B5A2-9C86C87A45DA@qualcomm.com> <20060615150456.GA7830@trixie.casa.cgf.cx> <20070228234326.GD9444@ns1.anodized.com> <45E61B10.4080208@portugalmail.pt> <20070301003511.GA4537@trixie.casa.cgf.cx> <45E62875.3090507@portugalmail.pt>
- Reply-to: cygwin at cygwin dot com
On Thu, Mar 01, 2007 at 01:12:21AM +0000, Pedro Alves wrote:
>Christopher Faylor escreveu:
>>On Thu, Mar 01, 2007 at 12:15:12AM +0000, Pedro Alves wrote:
>>>Is there a reason DebugBreakProcess can't be used from inside gdb if
>>>sending a ctrl-c with GenerateConsoleCtrlEvent (CTRL_C_EVENT, pid)
>>>doesn't work?
>>
>>I suppose that it could be used for that but it might be tricky
>>figuring out when it was required and when it wasn't. You wouldn't
>>want to interrupt the process twice if it already saw the CTRL-C.
>>Although, maybe if you used this you could tell the inferior process
>>not to process CTRL-C at all via some CreateProcess setting.
>
>What about doing it the other way around? Use DebugBreakProcess if
>available, and fallback to GenerateConsoleCtrlEvent?
? Maybe we're not talking about the same thing but I don't see why it
matters what the order of function calls is. If the inferior process
has already responded to a CTRL-C you don't want it to get another
interrupt.
>Is there anything internal to Cygwin that uses it? We could teach gdb
>that the next BreakPoint inside kernel32 (, or whatever dll
>DebugBreakProcess breaks in,) is mapped to SIGINT, remap the event, and
>switch to the main thread, so the user doesn't see we stopped inside
>kernel32.
I think if gdb sends a break because it saw a CTRL-C and then gets a
break from the sub-process it is safe for gdb to assume that the
interrupt was a CTRL-C without needing to check where the break hit. I
don't know about going to the effort of switching to thread 1, though.
cgf
--
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Problem reports: http://cygwin.com/problems.html
Documentation: http://cygwin.com/docs.html
FAQ: http://cygwin.com/faq/