p4raw-id: //depot/perl@26965
C<ptar> is a pure perl implementation of C<tar>, that comes with
C<Archive::Tar>.
+=head2 C<ptardiff>
+
+C<ptardiff> is a small script used to generate a diff between the contents
+of a tar archive and a directory tree. Like C<ptar>, it comes with
+C<Archive::Tar>.
+
=head2 C<shasum>
This command-line utility, used to print or to check SHA digests, comes