From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 7175 invoked from network); 9 Aug 2020 23:45:06 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 9 Aug 2020 23:45:06 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 0FBF09B60A; Mon, 10 Aug 2020 09:45:02 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 176849B609; Mon, 10 Aug 2020 09:44:22 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id B5A959B5D6; Mon, 10 Aug 2020 09:44:18 +1000 (AEST) Received: from viclamta04p.bpe.bigpond.com (viclamta04p.bpe.bigpond.com [203.38.21.68]) by minnie.tuhs.org (Postfix) with ESMTPS id DC6B19B5C7 for ; Mon, 10 Aug 2020 09:44:16 +1000 (AEST) Received: from smtp.telstra.com ([10.10.26.4]) by viclafep04p-svc.bpe.nexus.telstra.com.au with ESMTP id <20200809234414.BZZJ14548.viclafep04p-svc.bpe.nexus.telstra.com.au@smtp.telstra.com> for ; Mon, 10 Aug 2020 09:44:14 +1000 X-RG-Spam: Unknown X-RazorGate-Vade: gggruggvucftvghtrhhoucdtuddrgeduiedrkeejgddvhecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfupfevtfgpvffgnffuvffttedpqfgfvfenuceurghilhhouhhtmecugedttdenucenucfjughrpeffhffvufgjkfhffgggtgesthdttddttdervdenucfhrhhomhepffgrvhgvucfjohhrshhfrghllhcuoegurghvvgeshhhorhhsfhgrlhhlrdhorhhgqeenucggtffrrghtthgvrhhnpeekieetjeeuuefhfeeguedvudeifeevudfgvedtffekhfffjeekhfdutdetheethfenucfkphepuddutddrudeguddrudelfedrvdeffeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhephhgvlhhopegrnhgvuhhrihhnrdhhohhrshhfrghllhdrohhrghdpihhnvghtpeduuddtrddugedurdduleefrddvfeefpdhmrghilhhfrhhomhepoegurghvvgeshhhorhhsfhgrlhhlrdhorhhgqedprhgtphhtthhopeeothhuhhhssehtuhhhshdrohhrgheq X-RazorGate-Vade-Verdict: clean 0 X-RazorGate-Vade-Classification: clean X-RG-VS-CLASS: clean Received: from aneurin.horsfall.org (110.141.193.233) by smtp.telstra.com (5.8.420) id 5E8A564B1601364C for tuhs@tuhs.org; Mon, 10 Aug 2020 09:44:14 +1000 Received: from aneurin.horsfall.org (localhost [127.0.0.1]) by aneurin.horsfall.org (8.15.2/8.15.2) with ESMTP id 079NiDND003983 for ; Mon, 10 Aug 2020 09:44:13 +1000 (EST) (envelope-from dave@horsfall.org) Received: from localhost (dave@localhost) by aneurin.horsfall.org (8.15.2/8.15.2/Submit) with ESMTP id 079NiBdt003980 for ; Mon, 10 Aug 2020 09:44:13 +1000 (EST) (envelope-from dave@horsfall.org) X-Authentication-Warning: aneurin.horsfall.org: dave owned process doing -bs Date: Mon, 10 Aug 2020 09:44:11 +1000 (EST) From: Dave Horsfall To: The Eunuchs Hysterical Society In-Reply-To: <202008012112.071LCsdo037245@tahoe.cs.Dartmouth.EDU> Message-ID: References: <202008012112.071LCsdo037245@tahoe.cs.Dartmouth.EDU> User-Agent: Alpine 2.21.9999 (BSF 287 2018-06-16) X-GPG-Public-Key: http://www.horsfall.org/gpgkey.pub X-GPG-Fingerprint: 05B4 FFBC 0218 B438 66E0 587B EF46 7357 EF5E F58B X-Home-Page: http://www.horsfall.org/ X-Witty-Saying: "chmod 666 the_mode_of_the_beast" MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Subject: Re: [TUHS] Regular Expressions X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" On Sat, 1 Aug 2020, Doug McIlroy wrote: > This lesson came home with a vengeance when Al Aho wrote egrep, which > implemented full regular expressions as DFA's. I happened to be writing > calendar(1) at the same time, and used egrep to search calendar files > for dates in rather free formats for today and all days through the next > working day. [...] I heard somewhere (a Usenix paper?) that "egrep" turned out to be faster than "fgrep" (designed to look for fixed strings only), thus "egrep" is now symlinked everywhere. On my FreeBSD box (in /usr/bin): aneurin% ls -li *grep 25471 -r-xr-xr-x 7 root wheel 40744 Oct 15 2017 bsdgrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 bzegrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 bzfgrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 bzgrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 egrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 fgrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 grep 25471 -r-xr-xr-x 7 root wheel 40744 Oct 15 2017 lzegrep 25471 -r-xr-xr-x 7 root wheel 40744 Oct 15 2017 lzfgrep 25471 -r-xr-xr-x 7 root wheel 40744 Oct 15 2017 lzgrep 23554 lrwxr-xr-x 1 root wheel 10 Feb 18 2011 pgrep -> /bin/pgrep 25471 -r-xr-xr-x 7 root wheel 40744 Oct 15 2017 xzegrep 25471 -r-xr-xr-x 7 root wheel 40744 Oct 15 2017 xzfgrep 25471 -r-xr-xr-x 7 root wheel 40744 Oct 15 2017 xzgrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 zegrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 zfgrep 25480 -r-xr-xr-x 9 root wheel 82136 Oct 15 2017 zgrep OK, there's a few strays in there... -- Dave