[kwlug-disc] So why not tar -cf tarball.tar a.xz b.xz c.xz, instead of tar -cJf tarball.tar.xz a b c ?

[Chris Frey]

On Wed, Oct 26, 2016 at 11:24:55AM -0400, bob+kwlug at softscape.ca wrote:
> Hehe, I guess I'm going to be learning the structure of tar files soon.
> Now I'm curious.

There are libraries that like libarchive and libtar that handle
manipulation of tar archives.


> I'm going to try to find some documentation on the default tar format and play with PROG.sh as time permits. 
> 
> Although, I wonder if any of these:
> 
>      -H, --format FORMAT
>            create archive of the given formatFORMAT is one of the following:
> 
>            --format=gnu
>                  GNU tar 1.13.x format
> 
>            --format=oldgnu
>                  GNU format as per tar <= 1.12
> 
>            --format=pax
>                  POSIX 1003.1-2001 (pax) format
> 
>            --format=posix
>                  same as pax
> 
>            --format=ustar
>                  POSIX 1003.1-1988 (ustar) format
> 
>            --format=v7
>                  old V7 tar format
> 

The libarchive guys may have documentation.  It is a bit of a legacy minefield
once you venture into the tar format.

Interesting to geek out on though. :-)

- Chris