From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: zsh-workers-return-43677-ml=inbox.vuxu.org@zsh.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from primenet.com.au (ns1.primenet.com.au [203.24.36.2]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id d4bb8c5f for ; Thu, 11 Oct 2018 20:35:34 +0000 (UTC) Received: (qmail 3244 invoked by alias); 11 Oct 2018 20:35:23 -0000 Mailing-List: contact zsh-workers-help@zsh.org; run by ezmlm Precedence: bulk X-No-Archive: yes List-Id: Zsh Workers List List-Post: List-Help: List-Unsubscribe: X-Seq: 43677 Received: (qmail 2171 invoked by uid 1010); 11 Oct 2018 20:35:23 -0000 X-Qmail-Scanner-Diagnostics: from out3-smtp.messagingengine.com by f.primenet.com.au (envelope-from , uid 7791) with qmail-scanner-2.11 (clamdscan: 0.99.2/21882. spamassassin: 3.4.1. Clear:RC:0(66.111.4.27):SA:0(-2.6/5.0):. Processed in 0.851741 secs); 11 Oct 2018 20:35:23 -0000 X-Envelope-From: d.s@daniel.shahaf.name X-Qmail-Scanner-Mime-Attachments: | X-Qmail-Scanner-Zip-Files: | DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= daniel.shahaf.name; h=message-id:from:to:cc:mime-version :content-transfer-encoding:content-type:references:subject:date :in-reply-to; s=fm1; bh=Opi7ApVy227V/fWEP0H8h36ZQjz3chDH9kFZu4yK c0k=; b=LdqgcYnuHTgEIl1snPkA0cuznkjzh4v9VJA6MZLNncyECPyd0tyISO2C JIkBrm8SC8oUrhoBBHbtLoLETIFeUfhTBoU/f8WPlOMKE7qkyIvm3Y4iWjUqIe97 7YB3T4KwRZQ6IKOkojy2Wevf9XRF/xS3qx4HVTMj6FbhLkFSmddqs1Pb9nHUpmtf sdk9NiSvvTdRWseF8o7N5CcTI2NVKNaRwDuxxq5foZnYuGu37sNjSe5dSDX4QDAT aS/bVm3Dx9FXM5vg2xC3kPB0v3cbTVtKZfSv2eAV8h1NOSIh9v6J852WtAcf/ns3 DK64Y3VXZAZD+FncuGkEjtPX6PoO/Q== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm1; bh=Opi7ApVy227V/fWEP0H8h36ZQjz3chDH9kFZu4yKc 0k=; b=OIJ+vNhbLDJEesEKFPHdnYQzZmL/R+8AsW0Z6HqOQnIF39xZHMJ1WV8Pj wNnNuJOM7eWveWk4chrkXjeOyHOhVTIU72qSrQgroXq3ypbZRXPz1buPX2kLVZUW nqdTsb/y6BN/RxTw77c7U7FLxSy90VWrupg3GC639YlfeN9rTsVA3UhIpGT6i2b8 WxotGNkEzFaqIJ7TJY+t48vdkvFUsp2ZvBriLHYy5OOc7KJ4FSNLURfa6ybFGYeQ PZayGK7RLxVGXWAvXi3aky0uKgX3kRHpxl+iaCuTEqejLDwx7OiHEbdWkrsH1pLZ sW2w0vr1+/GFyOz/aoFZQq347ApCg== X-ME-Sender: X-ME-Proxy: Message-Id: <1539290119.4188692.1539037288.272C51E2@webmail.messagingengine.com> From: Daniel Shahaf To: Bart Schaefer , zsh-workers@zsh.org Cc: tvboyd23@gmail.com MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" X-Mailer: MessagingEngine.com Webmail Interface - ajax-6804a824 References: <8B27B616-9DDE-4A04-AA05-2EA7234051A0@dana.is> Subject: Re: Documentation about Multios is misleading, and perhaps untrue Date: Thu, 11 Oct 2018 20:35:19 +0000 In-Reply-To: Bart Schaefer wrote on Thu, 11 Oct 2018 12:12 -0700: > On Wed, Oct 10, 2018 at 9:05 PM dana wrote: > > > > On 10 Oct 2018, at 21:33, Tom Boyd wrote: > > >What should be done about this ? > > > > Not sure if there's really an issue with the rest > > A bit of common sense has to be applied here. These are redirection > operators and are going to behave first like redirection operators, > which means that the shell is going to open the file descriptors > before executing any of the commands, and then pass those descriptors > around. The semantics of redirections demands this. An external > command like "cat" receives a list of names in its argument list and > processes the names one by one, so it can completely open and close > the file with each name before moving on to the next one, but the > shell can't do that and would be broken in other cases if it tried. > > It's pointless to try to call call out every possible instance where > the fundamental semantics of shell operations affect a particular use > of the syntax. I won't disagree with such a broad statement, but on the other hand, I don't think "We shouldn't document this because this is how the OS limitations force us to implement the shell" is a useful stance, either. Readers of zshall(1) should not be assumed to be familiar with the C syscalls and library interfaces' limitations.