Alan,

On Fri, 21 Feb 2003, Patrick Welche wrote:

> with the p :-)
> tar xzvpf new.tgz

Just a quick explanation why...

The "p" is to preserve the file modes. The /usr/bin/su command is setuid
root; in other words, it runs with root's privileges (which is needed to
become another user).

   Jeremy C. Reed
   http://bsd.reedmedia.net/