From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id 4e7bb808 for ; Fri, 3 Jan 2020 23:01:29 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 948A395170; Sat, 4 Jan 2020 09:01:27 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id CF28C9516C; Sat, 4 Jan 2020 09:00:58 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id 7A4199516B; Sat, 4 Jan 2020 09:00:55 +1000 (AEST) X-Greylist: delayed 687 seconds by postgrey-1.36 at minnie.tuhs.org; Sat, 04 Jan 2020 09:00:54 AEST Received: from neener.bl.org (neener.bl.org [50.116.26.109]) by minnie.tuhs.org (Postfix) with ESMTP id E676095165 for ; Sat, 4 Jan 2020 09:00:54 +1000 (AEST) Received: from www.bl.org (neener.bl.org [50.116.26.109]) (authenticated bits=0) by neener.bl.org (8.15.2/8.15.2) with ESMTPSA id 003MnQdA005462 (version=TLSv1.2 cipher=DHE-RSA-AES128-GCM-SHA256 bits=128 verify=NO) for ; Fri, 3 Jan 2020 16:49:26 -0600 (CST) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 03 Jan 2020 16:49:26 -0600 From: Michael Parson To: tuhs@minnie.tuhs.org Organization: BL dot ORG In-Reply-To: References: <1inMKv-0Km-00@marmaro.de> <1inSly-4mJ-00@marmaro.de> Message-ID: X-Sender: mparson@bl.org User-Agent: Roundcube Webmail/1.3.8 X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.4.3 (neener.bl.org [50.116.26.109]); Fri, 03 Jan 2020 16:49:26 -0600 (CST) Subject: Re: [TUHS] sh: cmd | >file 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 2020-01-03 13:44, Warner Losh wrote: > On Fri, Jan 3, 2020, 1:39 PM markus schnalke wrote: > >> Hoi. >> >> [2020-01-03 13:45] markus schnalke >> > >> > I'd be interested in any stories and information around this >> > topic. >> >> Especially I'd like to know since when and why ``>file'' is a >> full command? Was it clever design or by accident? > > > It's used to open files in shell scripts. Iirc, exec >foo 5>& and the > like... I've also used it to truncate files: $ dd if=/dev/zero of=file count=10 10+0 records in 10+0 records out 5120 bytes (5.1 kB, 5.0 KiB) copied, 0.000686599 s, 7.5 MB/s $ ls -l file -rw-rw-r-- 1 mparson mparson 5120 Jan 3 16:45 file $ >file $ ls -l file -rw-rw-r-- 1 mparson mparson 0 Jan 3 16:46 file A more likely use case is to truncate a log file then HUP syslogd. -- Michael Parson Pflugerville, TX KF5LGQ