From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58797) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bwRFq-0001Gb-T4 for qemu-devel@nongnu.org; Tue, 18 Oct 2016 06:04:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bwRFm-0003qX-RS for qemu-devel@nongnu.org; Tue, 18 Oct 2016 06:04:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37290) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1bwRFm-0003qI-MN for qemu-devel@nongnu.org; Tue, 18 Oct 2016 06:04:14 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 528D590251 for ; Tue, 18 Oct 2016 10:04:13 +0000 (UTC) Date: Tue, 18 Oct 2016 11:04:10 +0100 From: "Daniel P. Berrange" Message-ID: <20161018100409.GH4349@redhat.com> Reply-To: "Daniel P. Berrange" References: <20161012191502.GC16187@work-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20161012191502.GC16187@work-vm> Subject: Re: [Qemu-devel] chardev's and fd's in monitors List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert" Cc: qemu-devel@nongnu.org, armbru@redhat.com On Wed, Oct 12, 2016 at 08:15:02PM +0100, Dr. David Alan Gilbert wrote: > Hi, > I had a look at a couple of readline like libraries; > editline and linenoise. A difficulty with using them is that > they both want fd's or FILE*'s; editline takes either but > from a brief look I think it's expecting to extract the fd. > That makes them tricky to integrate into qemu, where > the chardev's hide a whole bunch of non-fd things; in particular > tls, mux, ringbuffers etc. > > If we could get away with just a FILE* then we could use fopencookie, > but that's GNU only. > > Is there any sane way of shepherding all chardev's into having an > fd? The entire chardev abstraction model exists precisely because we cannot make all chardevs look like a single fd. Even those which are fd based may have separate FDs for input and output. IMHO the only viable approach would be to enhance linenoise/editline to not assume use of fd* or FILE * abstractions. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://entangle-photo.org -o- http://search.cpan.org/~danberr/ :|