--- loncom/loncnew	2003/09/15 09:24:49	1.23
+++ loncom/loncnew	2003/09/30 11:11:17	1.26
@@ -2,7 +2,7 @@
 # The LearningOnline Network with CAPA
 # lonc maintains the connections to remote computers
 #
-# $Id: loncnew,v 1.23 2003/09/15 09:24:49 foxr Exp $
+# $Id: loncnew,v 1.26 2003/09/30 11:11:17 foxr Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -45,6 +45,17 @@
 
 # Change log:
 #    $Log: loncnew,v $
+#    Revision 1.26  2003/09/30 11:11:17  foxr
+#    Add book-keeping hashes to support the re-init procedure.
+#
+#    Revision 1.25  2003/09/23 11:22:14  foxr
+#    Tested ability to receive sigusr2  This is now logged and must be
+#    properly implemented as a re-read of hosts and re-init of appropriate
+#    children.
+#
+#    Revision 1.24  2003/09/16 09:46:42  foxr
+#    Added skeletal infrastructure to support SIGUSR2 update hosts request.
+#
 #    Revision 1.23  2003/09/15 09:24:49  foxr
 #    Add use strict and fix all the fallout from that.
 #
@@ -141,12 +152,6 @@ use LONCAPA::HashIterator;
 #
 #   Disable all signals we might receive from outside for now.
 #
-#$SIG{QUIT}  = IGNORE;
-#$SIG{HUP}   = IGNORE;
-#$SIG{USR1}  = IGNORE;
-#$SIG{INT}   = IGNORE;
-#$SIG{CHLD}  = IGNORE;
-#$SIG{__DIE__}  = IGNORE;
 
 
 # Read the httpd configuration file to get perl variables
@@ -159,6 +164,8 @@ my %perlvar    = %{$perlvarref};
 #  parent and shared variables.
 
 my %ChildHash;			# by pid -> host.
+my %HostToPid;			# By host -> pid.
+my %HostHash;			# by loncapaname -> IP.
 
 
 my $MaxConnectionCount = 10;	# Will get from config later.
@@ -1518,6 +1525,7 @@ sub CreateChild {
     if($pid) {			# Parent
 	$RemoteHost = "Parent";
 	$ChildHash{$pid} = $RemoteHost;
+	$HostToPid{$host}= $pid;
 	sigprocmask(SIG_UNBLOCK, $sigset);
 
     } else {			# child.
@@ -1580,6 +1588,7 @@ while (! $HostIterator->end()) {
 
     my $hostentryref = $HostIterator->get();
     CreateChild($hostentryref->[0]);
+    $HostHash{$hostentryref->[0]} = $hostentryref->[4];
     $HostIterator->next();
 }
 $RemoteHost = "Parent Server";
@@ -1596,11 +1605,13 @@ $SIG{INT}  = \&Terminate;
 $SIG{TERM} = \&Terminate; 
 $SIG{HUP}  = \&Restart;
 $SIG{USR1} = \&CheckKids; 
+$SIG{USR2} = \&UpdateKids;	# LonManage update request.
 
 while(1) {
     my $deadchild = wait();
     if(exists $ChildHash{$deadchild}) {	# need to restart.
 	my $deadhost = $ChildHash{$deadchild};
+	delete($HostToPid{$deadhost});
 	delete($ChildHash{$deadchild});
 	Log("WARNING","Lost child pid= ".$deadchild.
 	      "Connected to host ".$deadhost);
@@ -1639,6 +1650,37 @@ sub CheckKids {
 
 =pod
 
+=head1  UpdateKids
+
+parent's SIGUSR2 handler.  This handler:
+
+=item
+
+Rereads the hosts file.
+
+=item
+ 
+Kills off (via sigint) children for hosts that have disappeared.
+
+=item
+
+HUP's children for hosts that already exist (this just forces a status display
+and resets the connection retry count for that host.
+
+=item
+
+Starts new children for hosts that have been added to the hosts.tab file since
+the start of the master program and maintains them.
+
+=cut
+
+sub UpdateKids {
+    Log("INFO", "Updating connections via SIGUSR2");
+}
+
+
+=pod
+
 =head1 Restart
 
 Signal handler for HUP... all children are killed and