Improve wording.

doc/src/sgml/ref/pg_controldata.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/ref/pg_controldata.sgml,v 1.1 2002/08/16 20:34:06 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/ref/pg_controldata.sgml,v 1.2 2002/08/16 20:36:25 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -33,6 +33,7 @@ PostgreSQL documentation
   </para>
 
   <para>
+   This utility may only be run by the user who installed the server.
    You can specify the data directory on the command line, or use 
    the environment variable <envar>PGDATA</>.
   </para>