From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54247) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dXtoK-0006Zh-E2 for qemu-devel@nongnu.org; Wed, 19 Jul 2017 14:35:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dXtoF-0005We-Hf for qemu-devel@nongnu.org; Wed, 19 Jul 2017 14:35:00 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39000) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dXtoF-0005WP-B1 for qemu-devel@nongnu.org; Wed, 19 Jul 2017 14:34:55 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4E3FF4A701 for ; Wed, 19 Jul 2017 18:34:54 +0000 (UTC) Date: Wed, 19 Jul 2017 15:34:47 -0300 From: Eduardo Habkost Message-ID: <20170719183447.GJ2757@localhost.localdomain> References: <20170719163108.26943-1-apahim@redhat.com> <20170719163108.26943-2-apahim@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170719163108.26943-2-apahim@redhat.com> Subject: Re: [Qemu-devel] [PATCH v2 1/3] qemu.py: fix is_running() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Amador Pahim Cc: qemu-devel@nongnu.org, berrange@redhat.com, mreitz@redhat.com, kwolf@redhat.com, armbru@redhat.com, crosa@redhat.com, ldoktor@redhat.com On Wed, Jul 19, 2017 at 06:31:06PM +0200, Amador Pahim wrote: > Current implementation is broken. It does not really test if the child > process is running. > > The Popen.returncode will only be set after by a poll(), wait() or > communicate(). If the Popen fails to launch a VM, the Popen.returncode > will not turn to None by itself. > > Instead of using Popen.returncode, let's use Popen.poll(), which > actually checks if child process has terminated. > > Signed-off-by: Amador Pahim I vaguely remember I had a version of that code using poll() and it broke scripts for some reason. I will try to find out why, so we can either fix the script or document the reason why poll() isn't a good choice here. > --- > scripts/qemu.py | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/scripts/qemu.py b/scripts/qemu.py > index 880e3e8219..f0fade32bd 100644 > --- a/scripts/qemu.py > +++ b/scripts/qemu.py > @@ -86,7 +86,7 @@ class QEMUMachine(object): > raise > > def is_running(self): > - return self._popen and (self._popen.returncode is None) > + return self._popen and (self._popen.poll() is None) > > def exitcode(self): > if self._popen is None: > -- > 2.13.3 > -- Eduardo