tar oddness

["E.L. Meijer \(Eric\)" <tgakem@sg10.chem.tue.nl>]

Hi all,

I was pondering on the problem of splitting output over multiple
mountable media, and discovered the following:

$ tar czf foo elmfract
$ tar czf - elmfract > bar
$ ls -l foo bar
-rw-r--r--   1 tgakem   users       10240 Mar 29 16:59 bar
-rw-r--r--   1 tgakem   users        7950 Mar 29 16:59 foo

The file bar is a valid archive, but contains trailing garbage.  Any
idea how this comes about?  It does not happen if the z flag to tar is
not present.

I noticed this when I wrote a small program that takes input from stdin
(through a pipe), and writes this to different files on different
volumes of a mountable medium (say, floppies).

Eric

-- 
 E.L. Meijer (tgakem@chem.tue.nl)
 Eindhoven Univ. of Technology
 Lab. for Catalysis and Inorg. Chem. (SKA)