From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 127028 invoked by alias); 16 Mar 2016 13:25:11 -0000 Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Received: (qmail 127011 invoked by uid 89); 16 Mar 2016 13:25:10 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.2 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 spammy=H*MI:sk:56E75B3, Hx-languages-length:1607, H*i:sk:56E75B3, hanging X-HELO: mail-wm0-f54.google.com Received: from mail-wm0-f54.google.com (HELO mail-wm0-f54.google.com) (74.125.82.54) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-GCM-SHA256 encrypted) ESMTPS; Wed, 16 Mar 2016 13:25:03 +0000 Received: by mail-wm0-f54.google.com with SMTP id l124so48591487wmf.1 for ; Wed, 16 Mar 2016 06:25:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=dk+D5AMl6kexh7UHAh00aZRovCofjz+LW/fX68tFF44=; b=MmSARFJE6n3ZenVVTPjFsPAaIf67y1o0bvfgDpfZ6QSw/paZCjuOEi05kBKopjZ6IL pABNDff+N9myqE6IYpUkCJMmhHRExUoFDnf9XWqjGnJiFJbDGS9m8bSNQVaBhl0/FjmR b3tHItwdO00aXVBoOy8HXzf4eoImpxUFmrJSlMqq9LwM3m2eJNX62b5HD+SvG3D8X+6W sRdwTQMDkyl1m+4NDhzYUEHw+D9epPh6swnDV6vsQLuiZ1AYMlraRsN02yHhgfz69rmR uWN8RVuswisReggKL8itNi1eIN4rL86Mf7GY4h3yA2RvSNbEW7I3whEmfgaRCX1Mb2vD dm2w== X-Gm-Message-State: AD7BkJJQsIgYiw+Yg8FmWIjaIFOHQGnVA9hl5JXlOsAIUjBdjQp3DcmE0mpGQma9vZXcOw== X-Received: by 10.28.48.136 with SMTP id w130mr30733312wmw.54.1458134700837; Wed, 16 Mar 2016 06:25:00 -0700 (PDT) Received: from [172.21.188.188] ([149.6.156.42]) by smtp.googlemail.com with ESMTPSA id hq2sm3086155wjb.3.2016.03.16.06.24.59 for (version=TLSv1/SSLv3 cipher=OTHER); Wed, 16 Mar 2016 06:24:59 -0700 (PDT) Subject: Re: ctrl-c doesn't reliably kill ping To: cygwin@cygwin.com References: <56E6F25A.7070000@gmx.de> <56E75B3E.7020102@farance.com> From: Marco Atzeri Message-ID: <56E95EA2.8070800@gmail.com> Date: Wed, 16 Mar 2016 13:25:00 -0000 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <56E75B3E.7020102@farance.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2016-03/txt/msg00312.txt.bz2 On 15/03/2016 01:45, Frank Farance wrote: > I have been having this problem with "ping". If I "ping" a location > that doesn't exist, then "ping" just hangs and cannot be killed via > "kill -KILL [pid]". > > > Back to the problem, so when I type > > $ ping some.unknown.host > I do not succeed to replicate. CTRL-C works fine for me $ type ping ping is hashed (/usr/bin/ping) $ ping 172.21.1.254 PING 172.21.1.254 (172.21.1.254): 56 data bytes ----172.21.1.254 PING Statistics---- 4 packets transmitted, 0 packets received, 100.0% packet loss or I have not a biased DNS answer. > according to "ping", the hostname resolves to 90.242.140.21 (as per the > explanation above), but I cannot kill "ping". I tried "ping" with a > limited packet size and count so, in theory, "ping" would die on its own > after 10 packets, such as: > > $ ping some.unknown.host 50 10 > > but it still hangs rather than timing out. If I ping to some actual IP > address that is unresponsive (route-able to the last subnet, but dies on > the floor at the end), then I can kill via ctrl-c. My only solution to > the hanging "ping" is to kill the terminal window. > > Any suggestions on: > > - Why "ping" behaves this way? > - How to avoid this problem? > > Thanks, in advance. cygwin ping is based on very old source from a time where people was not cheating on protocol answer. http://ftp.arl.mil/mike/ping.html (the author passed away 16 years ago..) can you send me a strace to see where the program is stacking ? No promise to find a solution but I will look on it. Regards Marco -- 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