From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.2 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id C095D1F453 for ; Sat, 9 Feb 2019 21:54:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726962AbfBIVyx (ORCPT ); Sat, 9 Feb 2019 16:54:53 -0500 Received: from bsmtp7.bon.at ([213.33.87.19]:32486 "EHLO bsmtp7.bon.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726898AbfBIVyw (ORCPT ); Sat, 9 Feb 2019 16:54:52 -0500 Received: from dx.site (unknown [93.83.142.38]) by bsmtp7.bon.at (Postfix) with ESMTPSA id 43xm6x4y7dz5tlB; Sat, 9 Feb 2019 22:54:49 +0100 (CET) Received: from [IPv6:::1] (localhost [IPv6:::1]) by dx.site (Postfix) with ESMTP id 1C2EF1EA9; Sat, 9 Feb 2019 22:54:49 +0100 (CET) Subject: Re: [Fix v2] t5562: remove dependency on /dev/zero To: Junio C Hamano Cc: randall.s.becker@rogers.com, git@vger.kernel.org, "Randall S. Becker" References: <20190208220751.9936-1-randall.s.becker@rogers.com> From: Johannes Sixt Message-ID: <8da682c1-aad2-ab83-9e46-6b7d4a6c68bd@kdbg.org> Date: Sat, 9 Feb 2019 22:54:48 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Am 09.02.19 um 19:25 schrieb Junio C Hamano: > Johannes Sixt writes: > >> How many bytes are needed here? yes() in test-lib.sh generates only 99 >> 'y', if I am not mistaken. > > I think we will not use "yes" in the end for this topic, which makes > this comment totally irrelevant to the thread, but I wonder why we > have the limit of 99 there? It cannot be "we do not want to worry > about sigpipe" affecting the end result of the test (after all the > reader may stop reading from after reading just one, and the status > of the upstream process that would die with sigpipe is lost anyway). > > It turns out it is about sigpipe ;-) but in somewhat a different > way. To prevent others from wasting their time wondering about > this, probably we want to have something like the attached? That would certainly be helpful! -- Hannes > > t/README | 9 +++++++++ > t/test-lib.sh | 6 +++++- > 2 files changed, 14 insertions(+), 1 deletion(-) > > diff --git a/t/README b/t/README > index 1326fd7505..f4e1a82657 100644 > --- a/t/README > +++ b/t/README > @@ -927,6 +927,15 @@ library for your script to use. > test_oid_init or test_oid_cache. Providing an unknown key is an > error. > > + - yes [] > + > + This is often seen in modern UNIX but some platforms lack it, so > + the test harness overrides the platform implementation with a > + more limited one. Use this only when feeding a handful lines of > + output to the downstream---unlike the real version, it generates > + only up to 99 lines. > + > + > Prerequisites > ------------- > > diff --git a/t/test-lib.sh b/t/test-lib.sh > index 42b1a0aa7f..541a37f4c0 100644 > --- a/t/test-lib.sh > +++ b/t/test-lib.sh > @@ -1313,7 +1313,11 @@ then > fi > fi > > -# Provide an implementation of the 'yes' utility > +# Provide an implementation of the 'yes' utility; the upper bound > +# limit is there to help Windows that cannot stop this loop from > +# wasting cycles when the downstream stops reading, so do not be > +# tempted to turn it into an infinite loop. cf. 6129c930 ("test-lib: > +# limit the output of the yes utility", 2016-02-02) > yes () { > if test $# = 0 > then >