You don't share files, you offer a service that shares a directory.
Could you explain what you mean by sharing disk spaces?
Your distro may have a wizard for offering nfs services. It may be called nfs-server.
If nfs is installed you edit an /etc/exports file to define which directories to export.
See the manpages for nfs and exports.
Last edited by jschiwal; 02-02-2008 at 04:36 AM.