Re: [found the culprit]

[Stefan Monnier <monnier@iro.umontreal.ca>]

>> Unfortunately some sites require to upload files in tar format and not
>> in tar.gz format.

Something like Dired's `Z` can't satisfy all imaginable cases, so the
fact some odd cases require the generation of uncompressed .tar file
shouldn't make much a difference in deciding what behavior we want.

> Yes.  Upload, download, email...  It's quite possible for
> a user to obtain a tar file, regardless of whether Stefan -

The question is not "what do we do when we receive an uncompressed tar
file", but rather "what do we do when we have a compressed tar file" and
"what do we do when the user requests to compress a directory".

> or even everyone here - considers tar.gz to be the only
> useful archive format.

Noone said tar.gz is the only useful format.  I just pointed out that in
my experience ".tar.gz" is itself considered as an archive format rather
than "a compressed file which contains an archive" in the sense that in
the vast majority of cases people take a directory and pack it up into
a .tar.gz "tarball" or take a ".tar.gz" and unpack it into a directory
tree: the cases where the .tar intermediate step is used explicitly are
much less frequent.

> The question is whether `Z' should support tar files.

No.  It does and has done so for a long time and there's no suggestion
to make it stop supporting it.

And indeed Dired's `Z` has been compressing directories to tar.gz and
uncompressing tar.gz to directories (rather than to tar files) for many
years now.


        Stefan