From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 55668CA0EEB for ; Tue, 19 Aug 2025 16:00:02 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1uoOjy-0003Ej-GO; Tue, 19 Aug 2025 11:59:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uoOju-0003Db-3T for qemu-devel@nongnu.org; Tue, 19 Aug 2025 11:59:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1uoOjr-0005K9-AZ for qemu-devel@nongnu.org; Tue, 19 Aug 2025 11:59:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1755619143; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=hGSKVmlMEKu/j0HHDJU/geySDvt42YgNjcBsovx4w+s=; b=g04JbRooM117PPEA0rd4YRpG4tOVg5l3CJ0wkrJ7TX10VHWgvgE/9tq7QQAqOwkHkbck17 2nKelRY3IEsk2cWLN5RUO20x8URhhP295ef+kHvbVHF0NV/QDnAXoRaEC5uJTnhJARyqA/ PsUN8NuFF7TqzAQPC6AyitgPj+3nad8= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-96-ieXU7em-OAOQqyn9c6VUzA-1; Tue, 19 Aug 2025 11:58:55 -0400 X-MC-Unique: ieXU7em-OAOQqyn9c6VUzA-1 X-Mimecast-MFC-AGG-ID: ieXU7em-OAOQqyn9c6VUzA_1755619134 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4A3EF180034F; Tue, 19 Aug 2025 15:58:53 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.237]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id D8EB63000198; Tue, 19 Aug 2025 15:58:49 +0000 (UTC) Date: Tue, 19 Aug 2025 16:58:45 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Stefan Hajnoczi Cc: qemu-devel@nongnu.org, Michael Roth , Markus Armbruster , Paolo Bonzini , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Mads Ynddal , Alex =?utf-8?Q?Benn=C3=A9e?= , Thomas Huth , oleg.tolmatcev@gmail.com Subject: Re: [PATCH v3 5/8] tracetool: support "-" as a shorthand for stdout Message-ID: References: <20250806164832.1382919-1-berrange@redhat.com> <20250806164832.1382919-6-berrange@redhat.com> <20250807194608.GF51368@fedora> <20250818175548.GA16685@fedora> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250818175548.GA16685@fedora> User-Agent: Mutt/2.2.14 (2025-02-20) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, Aug 18, 2025 at 01:55:48PM -0400, Stefan Hajnoczi wrote: > On Mon, Aug 18, 2025 at 04:07:28PM +0100, Daniel P. Berrangé wrote: > > On Thu, Aug 07, 2025 at 03:46:08PM -0400, Stefan Hajnoczi wrote: > > > On Wed, Aug 06, 2025 at 05:48:29PM +0100, Daniel P. Berrangé wrote: > > > > This avoids callers needing to use the UNIX-only /dev/stdout > > > > workaround. > > > > > > > > Signed-off-by: Daniel P. Berrangé > > > > --- > > > > scripts/tracetool/__init__.py | 8 ++++++-- > > > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/scripts/tracetool/__init__.py b/scripts/tracetool/__init__.py > > > > index 0f33758870..c8fd3a7ddc 100644 > > > > --- a/scripts/tracetool/__init__.py > > > > +++ b/scripts/tracetool/__init__.py > > > > @@ -38,8 +38,12 @@ def error(*lines): > > > > > > > > def out_open(filename): > > > > global out_filename, out_fobj > > > > - out_filename = posix_relpath(filename) > > > > - out_fobj = open(filename, 'wt') > > > > + if filename == "-": > > > > + out_filename = "[stdout]" > > > > > > A few lines above: > > > > > > out_filename = '' > > > out_fobj = sys.stdout > > > > > > Stick to '' here for consistency? > > > > Curious - that suggests that it was intended to be able to write to > > stdout by default, but tracetool.py unconditionally calls out_open() > > so those default assignments are effectively dead code, unless this > > internal code is called by something other than the tracetool.py main > > entrypoint ? > > > > I guess I'd be inclined to change the global initialization to just > > be 'None' to make it explicit that out_open is expected to always be > > called ? > > Originally the script wrote to stdout, but I added an explicit output > filename argument in commit c05012a365c2 ("tracetool: add output > filename command-line argument") because #line directives emitted by > tracetool need to know the output filename. > > Your next patch tests/tracetool/tracetool-test.py uses "-" as the > output filename but leaves the existing meson.build files unchanged. > They will still specify an output filename. > > This commit doesn't break anything, at least not in how this patch > series uses "-", but I see a contradiction with commit c05012a365c2 > since we're now allowing the output filename to be effectively empty. > > Could you avoid special casing stdout and instead pass a relative path > to the output file? The relative path is important so the test reference > output is portable across machines. Then you don't need this commit. If I copy the 'trace-events' file into the build-dir, then I can rely on relative files for both the input & output, and avoid need to support '-'. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|