Mailing-List: contact cygwin-help AT sourceware DOT cygnus DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT sources DOT redhat DOT com Delivered-To: mailing list cygwin AT sources DOT redhat DOT com X-Originating-IP: [24.0.161.175] From: "Karl M" To: karlm30 AT hotmail DOT com, cygwin AT cygwin DOT com Subject: Re: ssh hanging with -f option Date: Wed, 29 Aug 2001 07:30:52 -0700 Mime-Version: 1.0 Content-Type: text/plain; format=flowed Message-ID: X-OriginalArrivalTime: 29 Aug 2001 14:30:52.0937 (UTC) FILETIME=[34EF2F90:01C13097] Hi All... Can someone else take a look at debugging this? In a win2k environment, ssh -f localhost sleep 10 or ssh -f localhost echo test for example hang with all of the current released software. See below for more deails. Thanks, ...Karl >From: "Karl M" >To: cygwin AT cygwin DOT com >Subject: ssh hanging with -f option--a workaround >Date: Fri, 27 Jul 2001 07:08:31 -0700 > >Hi All... > >I first saw the following problem with openssh-2.5.2p1 or 2.9p1. The >problem >is that when I use the -f option with the ssh client, it hangs (with >CygWin). I checked my patch file against openssh-2.9p2-3. Because several >others have had this same problem, my updated patch is attached for anyone >who needs to use the -f option to ssh. > >I don't have a solution to the ssh hanging problem when it is forked off as >in > >ssh -f localhost sleep 10 > >but have a workaround. The patch file is attached. > >I looked at both ssh and sshd when they hang (both in their respective >select calls--which makes sense because they are both waiting for something >to do). The problem is in ssh. When ssh is forked after authentication, the >select call fails to return after the fifth time that it is invoked. This >problem only seems to occur when ssh has invoked daemon before starting the >interactive session, but the problem shows up four select calls later. As >part of my debugging, I forced select to return by setting a timeout. The >timeout does force it to return--and in fact, there is IO waiting to be >processed. So a one second timeout in the select call is my workaround for >now. > >The read and write bit masks before and after the select call always look >fine. It is not an ssh bug as far as I can tell. > >ssh localhost sleep 10 > >ssh -f localhost sleep 10 > >are the two test cases I used for debugging--to compare the behavior. > >Thanks, > >...Karl > > > >_________________________________________________________________ >Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp ><< OpenSSH-2.9p2-3-Hang-Patch >> >-- >Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple >Bug reporting: http://cygwin.com/bugs.html >Documentation: http://cygwin.com/docs.html >FAQ: http://cygwin.com/faq/ _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/