DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:date:from:to:subject:message-id:reply-to
	:references:mime-version:content-type:in-reply-to; q=dns; s=
	default; b=dzfc05VegvgztDgM6Kje3ZacbBLfdrblr4PZEuO3gUuQhYpNxPZGY
	27yCSZmjtK4KrcmkRPX0fWSQzzKxcRkuw8UdB4hCeqZkUgEHSWuofhPFJaYc6Zuz
	JzOZ4uWOmG7H9kS0PqVDB7FvisxDsdUrAFLHgoh+xzuGsfjkRbmNgc=
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Date: Tue, 29 Oct 2013 15:21:54 -0400
From: Christopher Faylor <cgf-use-the-mailinglist-please AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: SIGKILL and TerminateProcess
Message-ID: <20131029192154.GB5787@ednor.casa.cgf.cx>
Reply-To: cygwin AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
References: <5F8AAC04F9616747BC4CC0E803D5907D0C40AFEB AT MLBXv04 DOT nih DOT gov> <20131029172205 DOT GA1433 AT ednor DOT casa DOT cgf DOT cx> <5F8AAC04F9616747BC4CC0E803D5907D0C40B0C6 AT MLBXv04 DOT nih DOT gov>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <5F8AAC04F9616747BC4CC0E803D5907D0C40B0C6@MLBXv04.nih.gov>
User-Agent: Mutt/1.5.20 (2009-06-14)

On Tue, Oct 29, 2013 at 06:37:46PM +0000, Lavrentiev, Anton (NIH/NLM/NCBI) [C] wrote:
>> Sorry but we aren't going to redesign the signal delivery mechanism for
>> your use case.
>
>It wasn't exactly a redesign I was asking about;  rather an addition
>(or an improvement, if you will) for only the case of that one KILL
>signal, which is already a special thing in all aspects even on UNIX.

As the person who wrote the signal handling code, I think I get to
specify what I consider to be a redesign.

>>Cygwin does not guarantee delivery of signals to processes which are
>>calling Windows API functions directly.  If you do that you should be
>>prepared to deal with problems.
>
>Windows Sleep() was just a convenient dummy to demonstrate how SIGKILL
>does not kill.

You may notice that I didn't specify Sleep() in my explanation.

>CYGWIN lets me access some Windows-specific APIs (the same way one
>would do by using some UNIX-flavor-specific libraries), without having
>to port them all to CYGWIN first.  Such code becomes a real problem in
>pipelining because it cannot be reliably managed from other processes
>(which would all require modifications to do TerminateProcess tricks
>throughout; or use the special CYGWIN command-like utility) where just
>kill(9) would have been sufficient..

To be a broken record: The whole point of Cygwin is to run UNIX based
programs on Windows.  Asking for the addition of special-case code so
that people can use Windows functions in their programs completely
misses the point of this project.

That said, however, the Cygwin "kill" command does have a "-f" option
which forces the termination of a process if it can't be killed with
Cygwin's signal mechanism (I added it so that I could kill processes
that were hung while I was working on Cygwin's signal code).  If it is
essential that you be able to summarily terminate Windows programs then
use that.

Otherwise, I guarantee that continuing to insist that you need this will
avail you naught.  Your suggested change is not going to be implemented.

cgf

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple