Date: Fri, 3 Jul 2015 21:31:48 +0300
From: Lasse Collin <lasse.collin@tukaani.org>
To: Michael Fox <415fox@gmail.com>
Cc: alpine-devel <alpine-devel@lists.alpinelinux.org>, ncopa@alpinelinux.org
Subject: [alpine-devel] Re: xzdiff in xz package is broken on alpine linux
Message-ID: <20150703213148.2060418c@tukaani.org>
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On 2015-06-30 Michael Fox wrote:
> I have to admit the xzdiff script is a little beyond me but the way
> xzdiff fails is you compare two different files and it just returns 0
> as if they were the same. I think the easiest way to see it is to
> download  an alpine linux live CD:
> 
> http://alpinelinux.org/downloads/
> 
> To make it run in a VM takes just a few minutes. Here is complete
> steps to make it simple as possible:

Thanks. The diffs you sent didn't help, so I tested it under Alpine
Linux as you suggested. The problem is BusyBox diff which doesn't work
correctly if both arguments are pipes. Installing GNU diffutils makes
the problem go away.

Here is a simple test case using bash and other shells that support
the <(foo) syntax:

    bash$ echo foo | diff <(echo bar) - ; echo $?
    1c1
    < bar
    ---
    > foo
    1

Switching to BusyBox diff:

    bash$ echo foo | busybox diff <(echo bar) - ; echo $?
    0

For me it would be convenient if you could report the bug to the BusyBox
developers, but I can do it too if you prefer so. Thanks!

-- 
Lasse Collin  |  IRC: Larhzu @ IRCnet & Freenode


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