From: Robert Klemme <shortcutter@...>
Date: 2008-09-16T03:57:47+09:00
Subject: Re: how to stream or write data into a tar.gz file as if the data were    from files?

On 15.09.2008 20:35, bwv549 wrote:
> I have a gazillion little files in memory (each is really just a chunk
> of data, but it represents what needs to be a single file) and I need
> to throw them all into a .tar.gz archive.  In this case, it must be
> in .tar.gz format and it must unzip into actual files--although I pity
> the fellow that actually has to unzip this monstrosity.

> 3. Not portable, but fast:
>     stream information into tar/gzip to create the archive (without
> ever first writing out files)
> 
> I've been looking around on this and the closest I've come is this:
> tar cvf - some_directory | gzip - > some_directory.tar.gz
> 
> Note that this would still require me to write the files to a
> directory (which must be avoided at all costs), but at least the
> problem now is how to write data into a tar file.  I've been googling
> and still haven't turned up anything yet.

So why then do you say "without ever first writing out files"?

I'd say #3 (the original formulation) is the one to go.  Googling for 
"ruby tar" quickly turned up this:

http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/32588

And there is zlib which allows to read and write GZip streams.  So, if 
ruby-tar allows to write into any stream you got your solution.

Kind regards

	robert