--- loncom/lond	2003/09/15 10:03:52	1.143
+++ loncom/lond	2003/09/16 09:47:01	1.144
@@ -2,7 +2,7 @@
 # The LearningOnline Network
 # lond "LON Daemon" Server (port "LOND" 5663)
 #
-# $Id: lond,v 1.143 2003/09/15 10:03:52 foxr Exp $
+# $Id: lond,v 1.144 2003/09/16 09:47:01 foxr Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -60,6 +60,9 @@
 # 09/08/2003 Ron Fox:  Told lond to take care of change logging so we
 #      don't have to remember it:
 # $Log: lond,v $
+# Revision 1.144  2003/09/16 09:47:01  foxr
+# Added skeletal support for SIGUSR2 (update hosts.tab)
+#
 # Revision 1.143  2003/09/15 10:03:52  foxr
 # Completed and tested code for pushfile.
 #
@@ -97,7 +100,7 @@ my $DEBUG = 0;		       # Non zero to ena
 my $status='';
 my $lastlog='';
 
-my $VERSION='$Revision: 1.143 $'; #' stupid emacs
+my $VERSION='$Revision: 1.144 $'; #' stupid emacs
 my $remoteVERSION;
 my $currenthostid;
 my $currentdomainid;
@@ -485,6 +488,19 @@ sub HUPSMAN {                      # sig
     exec("$execdir/lond");         # here we go again
 }
 
+#
+#   Called in response to a USR2 signal.
+#   - Reread hosts.tab
+#   - All children connected to hosts that were removed from hosts.tab
+#     are killed via SIGINT
+#   - All children connected to previously existing hosts are sent SIGUSR1
+#   - Our internal hosts hash is updated to reflect the new contents of
+#     hosts.tab causing connections from hosts added to hosts.tab to
+#     now be honored.
+#
+sub UpdateHosts {
+}
+
 sub checkchildren {
     &initnewstatus();
     &logstatus();
@@ -727,7 +743,7 @@ $SIG{CHLD} = \&REAPER;
 $SIG{INT}  = $SIG{TERM} = \&HUNTSMAN;
 $SIG{HUP}  = \&HUPSMAN;
 $SIG{USR1} = \&checkchildren;
-
+$SIG{USR2} = \&UpdateHosts;
 
 
 # --------------------------------------------------------------
@@ -2501,6 +2517,17 @@ each connection is logged.
 
 =item *
 
+SIGUSR2
+
+Parent Signal assignment:
+    $SIG{USR2} = \&UpdateHosts
+
+Child signal assignment:
+    NONE
+
+
+=item *
+
 SIGCHLD
 
 Parent signal assignment: