--- loncom/lond	2020/01/13 13:41:24	1.489.2.35
+++ loncom/lond	2020/05/04 15:15:16	1.489.2.36
@@ -2,7 +2,7 @@
 # The LearningOnline Network
 # lond "LON Daemon" Server (port "LOND" 5663)
 #
-# $Id: lond,v 1.489.2.35 2020/01/13 13:41:24 raeburn Exp $
+# $Id: lond,v 1.489.2.36 2020/05/04 15:15:16 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -63,7 +63,7 @@ my $DEBUG = 0;		       # Non zero to ena
 my $status='';
 my $lastlog='';
 
-my $VERSION='$Revision: 1.489.2.35 $'; #' stupid emacs
+my $VERSION='$Revision: 1.489.2.36 $'; #' stupid emacs
 my $remoteVERSION;
 my $currenthostid="default";
 my $currentdomainid;
@@ -4576,6 +4576,45 @@ sub course_lastaccess_handler {
 }
 &register_handler("courselastaccess",\&course_lastaccess_handler, 0, 1, 0);
 
+sub course_sessions_handler {
+    my ($cmd, $tail, $client) = @_;
+    my $userinput = "$cmd:$tail";
+    my ($cdom,$cnum,$lastactivity) = split(':',$tail);
+    my $dbsuffix = '_'.$cdom.'_'.$cnum.'.db';
+    my (%sessions,$qresult);
+    my $now=time;
+    if (opendir(DIR,$perlvar{'lonIDsDir'})) {
+        my $filename;
+        while ($filename=readdir(DIR)) {
+            next if ($filename=~/^\./);
+            next if ($filename=~/^publicuser_/);
+            next if ($filename=~/^[a-f0-9]+_(linked|lti_\d+)\.id$/);
+            if ($filename =~ /^($LONCAPA::match_user)_\d+_($LONCAPA::match_domain)_/) {
+                my ($uname,$udom) = ($1,$2);
+                next unless (-e "$perlvar{'lonDaemons'}/$uname$dbsuffix");
+                my $mtime = (stat("$perlvar{'lonIDsDir'}/$filename"))[9];
+                my $since=$now-$mtime;
+                if ($lastactivity < 0) {
+                    next if ($since <= $lastactivity);
+                } else {
+                    next if ($since > $lastactivity);
+                }
+                $sessions{$uname.':'.$udom} = $mtime;
+            }
+        }
+        closedir(DIR);
+    }
+    foreach my $user (keys(%sessions)) {
+        $qresult.=&escape($user).'='.$sessions{$user}.'&';
+    }
+    if ($qresult) {
+        chop($qresult);
+    }
+    &Reply($client, \$qresult, $userinput);
+    return 1;
+}
+&register_handler("coursesessions",\&course_sessions_handler, 0, 1, 0);
+
 #
 # Puts an unencrypted entry in a namespace db file at the domain level 
 #