Date: Mon, 07 Dec 2015 12:17:39 -0700 From: Ian Lepore <ian@freebsd.org> To: Garrett Cooper <yaneurabeya@gmail.com> Cc: Warner Losh <imp@FreeBSD.org>, src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r291929 - head/tools/tools/nanobsd Message-ID: <1449515859.1358.11.camel@freebsd.org> In-Reply-To: <5FA6DD6B-C70B-4E5A-BD04-5897B02E5FC8@gmail.com> References: <201512071024.tB7AOcjr094296@repo.freebsd.org> <1449512013.1358.6.camel@freebsd.org> <5FA6DD6B-C70B-4E5A-BD04-5897B02E5FC8@gmail.com>
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On Mon, 2015-12-07 at 11:07 -0800, Garrett Cooper wrote: > > On Dec 7, 2015, at 10:13, Ian Lepore <ian@freebsd.org> wrote: > > > > > On Mon, 2015-12-07 at 10:24 +0000, Warner Losh wrote: > > > Author: imp > > > Date: Mon Dec 7 10:24:38 2015 > > > New Revision: 291929 > > > URL: https://svnweb.freebsd.org/changeset/base/291929 > > > > > > Log: > > > Make sure to quote the arg after -n and -z tests. > > > > While I am generally a quoting fanatic and would much rather > > overquote > > than underquote in shell scripts, fyi it's not actually needed for > > the > > -n and -z tests. test(1) and shells seem to be smart enough to see > > the > > ']' (which is just an arg to test, not shell language syntax) and > > know > > there isn't a string in front of it. > > Warner's commit was good. There's a more bulletproof way to do this > to make it more portable (in most cases, not all), but it would be > overkill: > > [ "x$x" != x ] > > Also, his commit protects against variables with spaces in them doing > unexpected things with test(1). > > Thanks, > -NGie Arrrgggghhhh! No no no no, a thousand times NO. There is NO EXCUSE for that ugly unnecessary xfoo stuff. Quoting properly supplies all the bulletproofing needed for string comparisons. It does look like I was wrong about all shells/test implementations handling the closing bracket for -n and -z as an empty-string indicator though, so quoting is a good solution for that. (Quoting is a good solution for everything, it drives me nuts that I can't use spaces in directory and filenames because so many unix scripts fall on their faces with parameter passing and other tricky quoting situations). -- Ian
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