class="parameter">port</replaceable></option></term>
    <listitem>
     <para>Database server's port.</para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><option>-U <replaceable>username</replaceable></option></term>
    <term><option>--username=<replaceable class="parameter">username</replaceable></option></term>
    <listitem>
     <para>User name to connect as.</para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><option>-w</option></term>
    <term><option>--no-password</option></term>
    <listitem>
     <para>
      Never issue a password prompt.  If the server requires password
      authentication and a password is not available by other means
      such as a <filename>.pgpass</filename> file, the connection
      attempt will fail.  This option can be useful in batch jobs and
      scripts where no user is present to enter a password.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><option>-W</option></term>
    <term><option>--password</option></term>
    <listitem>
     <para>
      Force <application>vacuumlo</application> to prompt for a
      password before connecting to a database.
     </para>

     <para>
      This option is never essential, since
      <application>vacuumlo</application> will automatically prompt
      for a password if the server demands password authentication.
      However, <application>vacuumlo</application> will waste a
      connection attempt finding out that the server wants a password.
      In some cases it is worth typing <option>-W</option> to avoid the extra
      connection attempt.
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
  </para>
 </refsect1>

 <refsect1>
  <title>Environment</title>

  <variablelist>
   <varlistentry>
    <term><envar>PGHOST</envar></term>
    <term><envar>PGPORT</envar></term>
    <term><envar>PGUSER</envar></term>

    <listitem>
     <para>
      Default connection parameters.
     </para>
    </listitem>
   </varlistentry>
  </variablelist>

  <para>
   This utility, like most other <productname>PostgreSQL</productname> utilities,
   also uses the environment variables supported by <application>libpq</application>
   (see <xref linkend="libpq-envars"/>).
  </para>

  <para>
   The environment variable <envar>PG_COLOR</envar> specifies whether to use
   color in diagnostic messages. Possible values are
   <literal>always</literal>, <literal>auto</literal> and
   <literal>never</literal>.
  </para>
 </refsect1>

 <refsect1>
  <title>Notes</title>

  <para>
   <application>vacuumlo</application> works by the following method:
   First, <application>vacuumlo</application> builds a temporary table which contains all
   of the OIDs of the large objects in the selected database.  It then scans
   through all columns in the database that are of type
   <type>oid</type> or <type>lo</type>, and removes matching entries from the temporary
   table.  (Note: Only types with these names are considered; in particular,
   domains over them are not considered.)  The remaining entries in the
   temporary table identify orphaned LOs.  These are removed.
  </para>
 </refsect1>

 <refsect1>
  <title>Author</title>

  <para>
   Peter Mount <email>peter@retep.org.uk</email>
  </para>
 </refsect1>

</refentry>