log_destination should only be PGC_SIGHUP, not PGC_POSTMASTER, as per

discussion yesterday.  Also a few improvements in the associated
documentation.

doc/src/sgml/maintenance.sgml

 <!--
-$PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.35 2004/05/16 19:34:46 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.36 2004/07/24 19:51:22 tgl Exp $
 -->
 
 <chapter id="maintenance">
@@ -456,7 +456,7 @@ VACUUM
    The simplest production-grade approach to managing log output is to
    send it all to <application>syslog</> and let
    <application>syslog</> deal with file rotation. To do this, set the
-   configurations parameter <literal>log_destination</> to 'syslog' (to log to
+   configuration parameter <literal>log_destination</> to 'syslog' (to log to
    <application>syslog</> only) in <filename>postgresql.conf</>. Then
    you can send a <literal>SIGHUP</literal> signal to the
    <application>syslog</> daemon whenever you want to force it to

doc/src/sgml/runtime.sgml

 <!--
-$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.269 2004/07/11 00:18:40 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.270 2004/07/24 19:51:22 tgl Exp $
 -->
 
 <Chapter Id="runtime">
@@ -1769,12 +1769,13 @@ SET ENABLE_SEQSCAN TO OFF;
       <listitem>
        <para>
 	<productname>PostgreSQL</productname> supports several methods
-	 for loggning, including <systemitem>stderr</systemitem> and
+	 for logging server messages, including
+	 <systemitem>stderr</systemitem> and
 	 <systemitem>syslog</systemitem>. On Windows, 
 	 <systemitem>eventlog</systemitem> is also supported. Set this
-	 option to a list of desired log destinations separated by a
-	 comma. The default is to log to <systemitem>stderr</systemitem> 
-	 only. This option must be set at server start.
+	 option to a list of desired log destinations separated by
+	 commas. The default is to log to <systemitem>stderr</systemitem> 
+	 only.
        </para>
       </listitem>
      </varlistentry>
@@ -1783,15 +1784,16 @@ SET ENABLE_SEQSCAN TO OFF;
       <term><varname>syslog_facility</varname> (<type>string</type>)</term>
        <listitem>
         <para>
-          This option determines the <application>syslog</application>
-          <quote>facility</quote> to be used when logging via
-          <application>syslog</application> is enabled. You may choose
+          If logging to <application>syslog</> is enabled, this option
+          determines the <application>syslog</application>
+          <quote>facility</quote> to be used.  You may choose
           from <literal>LOCAL0</>, <literal>LOCAL1</>,
           <literal>LOCAL2</>, <literal>LOCAL3</>, <literal>LOCAL4</>,
           <literal>LOCAL5</>, <literal>LOCAL6</>, <literal>LOCAL7</>;
           the default is <literal>LOCAL0</>. See also the
           documentation of your system's
-          <application>syslog</application>.
+          <application>syslog</application> daemon.
+	  This option can only be set at server start.
         </para>
        </listitem>
      </varlistentry>
@@ -1803,8 +1805,9 @@ SET ENABLE_SEQSCAN TO OFF;
          If logging to <application>syslog</> is enabled, this option
          determines the program name used to identify
          <productname>PostgreSQL</productname> messages in
-         <application>syslog</application> log messages. The default is
+         <application>syslog</application> logs. The default is
          <literal>postgres</literal>.
+	  This option can only be set at server start.
         </para>
        </listitem>
       </varlistentry>

src/backend/utils/misc/guc.c

@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.223 2004/07/21 20:34:46 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.224 2004/07/24 19:51:23 tgl Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -1625,8 +1625,8 @@ static struct config_string ConfigureNamesString[] =
 	},
 
 	{
-		{"log_destination", PGC_POSTMASTER, LOGGING_WHERE,
-		 gettext_noop("Sets the target for log output."),
+		{"log_destination", PGC_SIGHUP, LOGGING_WHERE,
+		 gettext_noop("Sets the destination for server log output."),
 		 gettext_noop("Valid values are combinations of stderr, syslog "
 					  "and eventlog, depending on platform."),
 		 GUC_LIST_INPUT
@@ -5099,15 +5099,12 @@ assign_log_destination(const char *value, bool doit, GucSource source)
 		}
 	}
 
+	if (doit)
+		Log_destination = newlogdest;
+
 	pfree(rawstring);
 	list_free(elemlist);
 
-	/* If we aren't going to do the assignment, just return OK indicator. */
-	if (!doit)
-		return value;
-
-	Log_destination = newlogdest;
-
 	return value;
 }