Mention that some psql environment variables come from libpq and note

more variables can be found in the libpq manual section.

Mention .pgpass in the psql manual page section dealing with connection
parameters and point to the libpq section for more details.

Backpatch to 8.0.X.

doc/src/sgml/ref/psql-ref.sgml

@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/ref/psql-ref.sgml,v 1.132 2005/01/22 23:22:19 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/ref/psql-ref.sgml,v 1.133 2005/02/11 04:19:05 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -348,7 +348,7 @@ PostgreSQL documentation
       <term><option>-u</></term>
       <listitem>
       <para>
-      Makes <application>psql</application> prompt for the user name and
+      Forces <application>psql</application> to prompt for the user name and
       password before connecting to the database.
       </para>
 
@@ -406,21 +406,25 @@ PostgreSQL documentation
       <term><option>--password</></term>
       <listitem>
       <para>
-      Cause <application>psql</application> to prompt for a
+      Forces <application>psql</application> to prompt for a
-      password before connecting to a database. This will remain set for
+      password before connecting to a database.  
-      the entire session, even if you change the database connection
-      with the meta-command <command>\connect</command>.
       </para>
 
       <para>
-      In the current version, <application>psql</application>
+      <application>psql</application> should automatically prompt for a
-      automatically issues a password prompt whenever the server
+      password whenever the server requests password authentication.
-      requests password authentication. Because this is currently based
+      However, currently password request detection is not totally
-      on a hack, the automatic recognition might mysteriously fail,
+      reliable, hence this option to force a prompt. If no password
-      hence this option to force a prompt. If no password prompt is
+      prompt is issued and the server requires password authentication,
-      issued and the server requires password authentication, the
+      the connection attempt will fail.
-      connection attempt will fail.
       </para>
+
+      <para>
+      This option will remain set for the entire session, even if you
+      change the database connection with the meta-command
+      <command>\connect</command>.
+      </para>
+
       </listitem>
     </varlistentry>
 
@@ -508,7 +512,10 @@ PostgreSQL documentation
     some typing by setting the environment variables
     <envar>PGDATABASE</envar>, <envar>PGHOST</envar>,
     <envar>PGPORT</envar> and/or <envar>PGUSER</envar> to appropriate
-    values.
+    values. (For additional environment variables, see <xref
+    linkend="libpq-envars">.) It is also convenient to have a
+    <filename>~/.pgpass</> file to avoid regularly having to type in
+    passwords. See <xref linkend="libpq-pgpass"> for more information.
     </para>
 
     <para>
@@ -2460,7 +2467,7 @@ $endif
 
     <listitem>
      <para>
-      Default database to connect to
+      Default connection database
      </para>
     </listitem>
    </varlistentry>