Subject: Re: bug#25458: 25.1; tar mode does not handle compressed archives without specific extensions

From: Lars Ingebrigtsen <[email-masked]>
Date: Fri, 13 May 2022 17:54:51 +0200

Francesco Potortì <[email-masked]> writes:

>>But I think the question is -- do we want to support this?  I'm not
>>quite sure -- it would be pretty unusual for a mode to do something like
>>this, and it's not clear what the semantics should be.  That is, if
>>we're saving the tar buffer afterwards, should it be compressed or not?
>>Either option would surprise somebody.
>
> Not really.  If I read a compressed file, Emacs uncompresses it when
> loading it to a buffer, then you can edit it and save it.  Compression
> and decompression are transparent.  I use this feature quite often,
> and so I am led to expect it of compressed archives too.  If it was
> compressed to begin with, it should be saved compressed too.

But the file name is "foo.tar" -- there'd be no way to tell Emacs that
the user wants to save that uncompressed.

You can load bar.gz into a buffer, and write out bar, and Emacs won't
compress that.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no