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From: Eitan Adler <lists@eitanadler.com>
Date: Thu, 5 Apr 2018 23:53:02 -0700
Message-ID: <CAF6rxgk+joSqoogqD=eWrjYTpOok+A_qSRFNOrZu58-crEfEMg@mail.gmail.com>
Subject: Re: Teach 'tar' to support more file types
To: Jun T <takimoto-j@kba.biglobe.ne.jp>
Cc: Zsh hackers list <zsh-workers@zsh.org>
Content-Type: text/plain; charset="UTF-8"

On 4 April 2018 at 20:55, Jun T <takimoto-j@kba.biglobe.ne.jp> wrote:
>
>> 2018/04/02 7:10, Eitan Adler <lists@eitanadler.com> wrote:
>>
>>    In libarchive based (BSD) tar implementations, all file types can be
>>    uncompressed, even without a filetype letter.  In GNU tar's case
>>    "recent" versions (for over 10 years) can do the same.
>>    As such, remove the check for tar type and just assume it works.
>
> We can't assume it works since there are many systems where tar requires
> explicit compression flags. Even on some BSDs (OpenBSD and NetBSD) tar
> is not based on libarchive.
>
> If the tar command is based on libarchive, we can detect it by using
> 'tar --version'.

This patch LGTM.


-- 
Eitan Adler