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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EF9DEC47255 for ; Mon, 11 May 2020 14:59:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7DAB20722 for ; Mon, 11 May 2020 14:59:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729711AbgEKO7Z convert rfc822-to-8bit (ORCPT ); Mon, 11 May 2020 10:59:25 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([146.101.78.151]:52467 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729120AbgEKO7Z (ORCPT ); Mon, 11 May 2020 10:59:25 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-157-TNtXyxpxO8qGl8Sa13yMrg-1; Mon, 11 May 2020 15:59:21 +0100 X-MC-Unique: TNtXyxpxO8qGl8Sa13yMrg-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Mon, 11 May 2020 15:59:20 +0100 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Mon, 11 May 2020 15:59:20 +0100 From: David Laight To: 'Masami Hiramatsu' CC: Shuah Khan , Steven Rostedt , "linux-kselftest@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Tom Zanussi , Li Philip , Liu Yiding , Xiao Yang , Andreas Schwab Subject: RE: [PATCH v2] selftests/ftrace: Use printf for backslash included command Thread-Topic: [PATCH v2] selftests/ftrace: Use printf for backslash included command Thread-Index: AQHWJ5lrSXqvrVhCTk6tpfgbVx7YuKii+RAg Date: Mon, 11 May 2020 14:59:20 +0000 Message-ID: References: <87imh21x6f.fsf@igel.home> <158920418730.16156.8299185499520876735.stgit@devnote2> <20200511223804.9483cab03c9221818ff4fc5b@kernel.org> In-Reply-To: <20200511223804.9483cab03c9221818ff4fc5b@kernel.org> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org > > + pos=$(printf "%s" "${2%^*}" | wc -c) # error position > > + command=$(printf "%s" "$2" | tr -d ^) You may want to put all the $(...) inside "" to avoid field splitting (not relevant to a shell assignment with modern shells) and filename globbing. > > echo "Test command: $command" > > echo > error_log > > - (! echo "$command" >> "$3" ) 2> /dev/null > > + (! printf "%s" "$command" >> "$3" ) 2> /dev/null WTF is the (! for ?? The (...) is a subshell. And ! inverts the exit status. Neither is needed at all. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)