From owner-sc22wg5+sc22wg5-dom8=www.open-std.org@open-std.org Fri Nov 18 09:58:49 2011 Return-Path: X-Original-To: sc22wg5-dom8 Delivered-To: sc22wg5-dom8@www.open-std.org Received: by www.open-std.org (Postfix, from userid 521) id 24C3535692E; Fri, 18 Nov 2011 09:58:49 +0100 (CET) Delivered-To: sc22wg5@open-std.org X-Greylist: delayed 935 seconds by postgrey-1.34 at www5.open-std.org; Fri, 18 Nov 2011 09:58:48 CET Received: from ppsw-51.csi.cam.ac.uk (ppsw-51.csi.cam.ac.uk [131.111.8.151]) by www.open-std.org (Postfix) with ESMTP id 7EAA73568D5 for ; Fri, 18 Nov 2011 09:58:48 +0100 (CET) X-Cam-AntiVirus: no malware found X-Cam-SpamDetails: not scanned X-Cam-ScannerInfo: http://www.cam.ac.uk/cs/email/scanner/ Received: from hermes-2.csi.cam.ac.uk ([131.111.8.54]:51051) by ppsw-51.csi.cam.ac.uk (smtp.hermes.cam.ac.uk [131.111.8.158]:25) with esmtpa (EXTERNAL:nmm1) id 1RRK2S-0005o4-X4 (Exim 4.72) (return-path ); Fri, 18 Nov 2011 08:43:12 +0000 Received: from prayer by hermes-2.csi.cam.ac.uk (hermes.cam.ac.uk) with local (PRAYER:nmm1) id 1RRK2S-00040D-3N (Exim 4.67) (return-path ); Fri, 18 Nov 2011 08:43:12 +0000 Received: from [83.67.89.123] by webmail.hermes.cam.ac.uk with HTTP (Prayer-1.3.4); 18 Nov 2011 08:43:12 +0000 Date: 18 Nov 2011 08:43:12 +0000 From: "N.M. Maclaren" To: sc22wg5 Subject: Re: [ukfortran] (SC22WG5.4590) (j3.2006) Comments on N1885 Message-ID: In-Reply-To: <20111118080228.4C55E35691F@www.open-std.org> References: <1319512507.24176.553.camel@math.jpl.nasa.gov><20111026183501.40C213568E1@www.open-std.org><4EA9CB87.1000505@cray.com> <20111027232707.8BEF13568FB@www.open-std.org> <20111118080228.4C55E35691F@www.open-std.org> X-Mailer: Prayer v1.3.4 Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset=ISO-8859-1 Sender: owner-sc22wg5@open-std.org Precedence: bulk On Nov 18 2011, Malcolm Cohen wrote: > > A Fortran procedure cannot do anything async without using async i/o > (already covered) or some of the coarray features (also already covered), > so in fact you cannot write a procedure in Fortran that is an async > communicator. I agree. There are only three leaves on the asynchronous communication procedure tree (those two, plus ones in the coprocessor, as you mentioned later). As I read it, Fortran's limited communication with the external environment (EXECUTE_COMMAND_LINE etc.) is specified to be synchronous. Van has a fair point in that a vendor could provide conforming extensions to the language that would enable asynchronicity (e.g. to turn functions into futures), but I don't see that causes any problems not already addressed. Regards, Nick.