Do not pass server_encoding to the client.

libpq, talking to an old server, should assume SQL_ASCII as the default
client encoding, because that is what the server will actually use (not
the server encoding).

doc/src/sgml/libpq.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/libpq.sgml,v 1.133 2003/08/31 17:32:19 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/libpq.sgml,v 1.134 2003/09/01 23:04:49 petere Exp $
 -->
 
  <chapter id="libpq">
@@ -856,21 +856,20 @@ is not known.
 <para>
 Parameters reported as of the current release include
 <literal>server_version</> (cannot change after startup);
-<literal>server_encoding</> (also not presently changeable after start);
 <literal>client_encoding</>,
 <literal>is_superuser</>, and
 <literal>DateStyle</>.
 </para>
 
 <para>
-Pre-3.0-protocol servers do not report parameter settings,
-but <application>libpq</> includes logic to obtain values for 
-<literal>server_version</>, <literal>server_encoding</>, and
-<literal>client_encoding</>.  Applications are encouraged to use
-<function>PQparameterStatus</> rather than ad-hoc code to determine these
-values.  (Beware however that on a pre-3.0 connection, changing
-<literal>client_encoding</> via <command>SET</> after connection startup
-will not be reflected by <function>PQparameterStatus</>.)
+Pre-3.0-protocol servers do not report parameter settings, but
+<application>libpq</> includes logic to obtain values for
+<literal>server_version</>, and <literal>client_encoding</>.
+Applications are encouraged to use <function>PQparameterStatus</>
+rather than ad-hoc code to determine these values.  (Beware however
+that on a pre-3.0 connection, changing <literal>client_encoding</> via
+<command>SET</> after connection startup will not be reflected by
+<function>PQparameterStatus</>.)
 </para>
 </listitem>
 </varlistentry>

doc/src/sgml/protocol.sgml

-<!-- $Header: /cvsroot/pgsql/doc/src/sgml/protocol.sgml,v 1.41 2003/08/14 20:09:31 tgl Exp $ -->
+<!-- $Header: /cvsroot/pgsql/doc/src/sgml/protocol.sgml,v 1.42 2003/09/01 23:04:49 petere Exp $ -->
 
 <chapter id="protocol">
  <title>Frontend/Backend Protocol</title>
@@ -1005,7 +1005,6 @@
     ParameterStatus will be generated: they are
     <literal>server_version</> (a pseudo-parameter that cannot change after
     startup);
-    <literal>server_encoding</> (also not presently changeable after start);
     <literal>client_encoding</>,
     <literal>is_superuser</>, and
     <literal>DateStyle</>.

src/backend/utils/misc/guc.c

@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.152 2003/09/01 04:15:50 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.153 2003/09/01 23:04:49 petere Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -1479,7 +1479,7 @@ static struct config_string ConfigureNamesString[] =
 		{"server_encoding", PGC_INTERNAL, CLIENT_CONN_LOCALE,
 			gettext_noop("Server (database) character set encoding"),
 			NULL,
-			GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
+			GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
 		},
 		&server_encoding_string,
 		"SQL_ASCII", NULL, NULL

src/interfaces/libpq/fe-protocol2.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-protocol2.c,v 1.7 2003/08/27 00:33:34 petere Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-protocol2.c,v 1.8 2003/09/01 23:04:49 petere Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -177,10 +177,10 @@ pqSetenvPoll(PGconn *conn)
 					 * must use begin/commit in case autocommit is off by
 					 * default in a 7.3 server.
 					 *
-					 * Note: version() and getdatabaseencoding() exist in all
+					 * Note: version() exists in all
 					 * protocol-2.0-supporting backends.
 					 */
-					if (!PQsendQuery(conn, "begin; select version(), getdatabaseencoding(); end"))
+					if (!PQsendQuery(conn, "begin; select version(); end"))
 						goto error_return;
 
 					conn->setenv_state = SETENV_STATE_QUERY1_WAIT;
@@ -213,8 +213,8 @@ pqSetenvPoll(PGconn *conn)
 						}
 
 						/*
-						 * Extract server version and database encoding,
-						 * and save as if ParameterStatus
+						 * Extract server version and save as if
+						 * ParameterStatus
 						 */
 						val = PQgetvalue(res, 0, 0);
 						if (val && strncmp(val, "PostgreSQL ", 11) == 0)
@@ -236,12 +236,6 @@ pqSetenvPoll(PGconn *conn)
 												  val);
 						}
 
-						val = PQgetvalue(res, 0, 1);
-						if (val && *val)		/* null should not happen,
-												 * but */
-							pqSaveParameterStatus(conn, "server_encoding",
-												  val);
-
 						PQclear(res);
 						/* Keep reading until PQgetResult returns NULL */
 					}
@@ -306,21 +300,17 @@ pqSetenvPoll(PGconn *conn)
 						else
 						{
 							/*
-							 * Error: presumably function not available,
-							 * so use PGCLIENTENCODING or database
-							 * encoding as the fallback.
+							 * Error: presumably function not
+							 * available, so use PGCLIENTENCODING or
+							 * SQL_ASCII as the fallback.
 							 */
 							val = getenv("PGCLIENTENCODING");
 							if (val && *val)
 								pqSaveParameterStatus(conn, "client_encoding",
 													  val);
 							else
-							{
-								val = PQparameterStatus(conn, "server_encoding");
-								if (val && *val)
-									pqSaveParameterStatus(conn, "client_encoding",
-														  val);
-							}
+								pqSaveParameterStatus(conn, "client_encoding",
+													  "SQL_ASCII");
 						}
 
 						PQclear(res);