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Processed in 3.703747 secs); 05 Jul 2019 13:45:09 -0000 X-Envelope-From: p.stephenson@samsung.com X-Qmail-Scanner-Mime-Attachments: | X-Qmail-Scanner-Zip-Files: | Received-SPF: pass (ns1.primenet.com.au: SPF record at _spf.samsung.com designates 210.118.77.12 as permitted sender) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20190705134428euoutp0262950436f261b14be9c0158dc63eb63f~uhr1HtPRS2352423524euoutp02E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1562334268; bh=Kl+El0QGBXsYVAVaFF0q9Mr4hx5QmWLzRFQfoAxJfp4=; h=Subject:From:To:Date:In-Reply-To:References:From; b=r8NUi38/G8lkUnYDZf+yUjoDP1G9ykW6EQ3LFNrl9tam2KNxznoF5wA8OZeDHgwkn 58eqAt+SgCbqfFAnbIe/h+MitBZDxysXnQThxoB9ew0UNcT2QFNGvwVm10L+uju38q CGHTguhLmUJGSPE2qfLlIljwAk7isMhtNwJrVoCY= X-AuditID: cbfec7f4-113ff70000001119-6e-5d1f543bd2b9 Message-ID: <1562334265.7053.11.camel@samsung.com> Subject: Re: zsh poor performances while reading and testing ? From: Peter Stephenson To: Date: Fri, 5 Jul 2019 14:44:25 +0100 In-Reply-To: <20190705132842.GA21074@prometheus.u-strasbg.fr> X-Mailer: Evolution 3.18.5.2-0ubuntu3.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrPIsWRmVeSWpSXmKPExsWy7djP87rWIfKxBj3LVS12nFzJ6MDoserg B6YAxigum5TUnMyy1CJ9uwSujOVvHzIXtLBV3Gp4z9bAeIuli5GTQ0LAROLMk4lANheHkMAK Ronujf/YIZweJolJU/+yQjjdTBInZ01ghGnZ1nKNGSKxnFHizOxnbHBVM8/eBasSEjjNKHFw qT5E4jyjxPuuVrCNvAJGEq0XljGB2MICdhL3v19iB7HZBAwlpm6aDdYsIiAu8WzmN7B6FgEV iZf3J7GC2JwCthJzH55hgzhDQ2LDzWNMEDMFJU7OfAJWzywgL9G8dTbYeRIC99kk5hz5yQTR 4CLRfHAdlC0s8er4FnYIW0bi/875TBAN7YwSaya9ZodwehglNh29A/W1tUTf7YtANgfQCk2J 9bv0IcKOEnsn/mcBCUsI8EnceCsIcQSfxKRt05khwrwSHW1CENVqEjuatjJChGUknq5RmMCo NAvJB7OQfDALYdUCRuZVjOKppcW56anFRnmp5XrFibnFpXnpesn5uZsYgcng9L/jX3Yw7vqT dIhRgINRiYf3hJN8rBBrYllxZe4hRgkOZiUR3sQgoBBvSmJlVWpRfnxRaU5q8SFGaQ4WJXHe aoYH0UIC6YklqdmpqQWpRTBZJg5OqQbGBfn/rpZ4Bkgblh7V9jFg59QzMnxineITppO+0u1R Qc63+mudrz5/2a0Um3GcUWfPiXrbdzOesuruLZOriVzz6pKXRuPZJ4fyeYVZs+KuXVDg8q+1 Wdk9USfqjrrF46fHFh5luvT/RPTvslcKFtcFLhRMPpi0LvqPDkN97cRgp3mN3crfrp5SYinO SDTUYi4qTgQAIknNfwIDAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmpmkeLIzCtJLcpLzFFi42I5/e/4PV2rEPlYg45nOhY7Tq5kdGD0WHXw A1MAY5SeTVF+aUmqQkZ+cYmtUrShhZGeoaWFnpGJpZ6hsXmslZGpkr6dTUpqTmZZapG+XYJe xvK3D5kLWtgqbjW8Z2tgvMXSxcjJISFgIrGt5RpzFyMXh5DAUkaJGd3noRIyEp+ufGSHsIUl /lzrYoMo6mSSmLdiKhOEc5pR4u6lnVDt5xkl5v+/xQbSwitgJNF6YRkTiC0sYCdx//slsFFs AoYSUzfNZgSxRQTEJZ7N/Aa2jkVAReLl/UmsIDangK3E3IdnoNYtYJJ42nEeLMEsoCnRuv03 1E0aEhtuHmOCWCYocXLmExaIGnmJ5q2zmScwCs1C0jILSdksJGULGJlXMYqklhbnpucWG+oV J+YWl+al6yXn525iBEbAtmM/N+9gvLQx+BCjAAejEg/vCSf5WCHWxLLiytxDjBIczEoivIlB QCHelMTKqtSi/Pii0pzU4kOMpkAfTWSWEk3OB0ZnXkm8oamhuYWlobmxubGZhZI4b4fAwRgh gfTEktTs1NSC1CKYPiYOTqkGxqDlgaKWF238S+7baEoVMdeIR264bb8/ylbYbnnhi5h20Zn2 HnxvueQPBb4v6U1WDOh+p25i8OjsGyuvtM9enoUdBueuBySvNwq9K6D9TcJ2h3nbKpVUDimH H1+YMyyawt9sYRGMnz15+czbT0TNdj5bkMKixFa4/MbhrLzPx9O9zk02tFBSYinOSDTUYi4q TgQAuEwkk5YCAAA= X-CMS-MailID: 20190705134427eucas1p2e0cf76f15046923fc1ba61e66f4f55b2 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" X-RootMTR: 20190705133007epcas2p2742e7257ea0d044352a2ed152c30245e X-EPHeader: CA CMS-TYPE: 201P X-CMS-RootMailID: 20190705133007epcas2p2742e7257ea0d044352a2ed152c30245e References: <20190703135824.GA19289__20170.6622539618$1562162400$gmane$org@prometheus.u-strasbg.fr> <20190703142831.dc762dlvgaxxvbmr@chaz.gmail.com> <20190705132842.GA21074@prometheus.u-strasbg.fr> On Fri, 2019-07-05 at 15:28 +0200, Marc Chantreux wrote:  > > You'll probably find that they are all as inefficient for > > non-seekable non-peekable input like pipes. > actually my point making this bench was: don't use shell to write > serious filters. however i really appreciate knowing why this difference > exists. thanks a lot. >  > >  > > IFS= read -r line > ok for -r but as long as i use only one variable, why is it important to > use IFS= ? As Look and Learn magazine used to say, Find Out By Doing. % read -r line   full line              ^^ spaces here % print -r -- "'$line'" '  full line  ' % read -r line   full line              ^^ spaces here % print -r -- "'$line'" 'full line' pws