--- loncom/lonnet/perl/lonnet.pm	2021/02/08 14:50:53	1.1442
+++ loncom/lonnet/perl/lonnet.pm	2021/04/09 02:01:11	1.1446
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.1442 2021/02/08 14:50:53 raeburn Exp $
+# $Id: lonnet.pm,v 1.1446 2021/04/09 02:01:11 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -4074,6 +4074,10 @@ sub clean_filename {
 # Replace all .\d. sequences with _\d. so they no longer look like version
 # numbers
     $fname=~s/\.(\d+)(?=\.)/_$1/g;
+# Replace three or more adjacent underscores with one for consistency 
+# with loncfile::filename_check() so complete url can be extracted by
+# lonnet::decode_symb()
+    $fname=~s/_{3,}/_/g;
     return $fname;
 }
 
@@ -9423,6 +9427,25 @@ sub auto_validate_instcode {
     return ($outcome,$description,$defaultcredits);
 }
 
+sub auto_validate_inst_crosslist {
+    my ($cnum,$cdom,$instcode,$inst_xlist,$coowner) = @_;
+    my ($homeserver,$response);
+    if (($cdom =~ /^$match_domain$/) && ($cnum =~ /^$match_courseid$/)) {
+        $homeserver = &homeserver($cnum,$cdom);
+    }
+    if (!defined($homeserver)) {
+        if ($cdom =~ /^$match_domain$/) {
+            $homeserver = &domain($cdom,'primary');
+        }
+    }
+    unless (($homeserver eq '') || ($homeserver eq 'no_host')) {
+        $response=&reply('autovalidateinstcrosslist:'.$cdom.':'.
+                         &escape($instcode).':'.&escape($inst_xlist).':'.
+                         &escape($coowner),$homeserver);
+    }
+    return $response;
+}
+
 sub auto_create_password {
     my ($cnum,$cdom,$authparam,$udom) = @_;
     my ($homeserver,$response);
@@ -10244,11 +10267,23 @@ sub autoupdate_coowners {
         if ($domdesign{$cdom.'.autoassign.co-owners'}) {
             my %coursehash = &coursedescription($cdom.'_'.$cnum);
             my $instcode = $coursehash{'internal.coursecode'};
+            my $xlists = $coursehash{'internal.crosslistings'};
             if ($instcode ne '') {
                 if (($start && $start <= $now) && ($end == 0) || ($end > $now)) {
                     unless ($coursehash{'internal.courseowner'} eq $uname.':'.$udom) {
                         my ($delcoowners,@newcoowners,$putresult,$delresult,$coowners);
                         my ($result,$desc) = &auto_validate_instcode($cnum,$cdom,$instcode,$uname.':'.$udom);
+                        unless ($result eq 'valid') {
+                            if ($xlists ne '') {
+                                foreach my $xlist (split(',',$xlists)) {
+                                    my ($inst_crosslist,$lcsec) = split(':',$xlist);
+                                    $result =
+                                        &auto_validate_inst_crosslist($cnum,$cdom,$instcode,
+                                                                      $inst_crosslist,$uname.':'.$udom);
+                                    last if ($result eq 'valid');
+                                }
+                            }
+                        }
                         if ($result eq 'valid') {
                             if ($coursehash{'internal.co-owners'}) {
                                 foreach my $coowner (split(',',$coursehash{'internal.co-owners'})) {
@@ -10261,18 +10296,16 @@ sub autoupdate_coowners {
                             } else {
                                 push(@newcoowners,$uname.':'.$udom);
                             }
-                        } else {
-                            if ($coursehash{'internal.co-owners'}) {
-                                foreach my $coowner (split(',',$coursehash{'internal.co-owners'})) {
-                                    unless ($coowner eq $uname.':'.$udom) {
-                                        push(@newcoowners,$coowner);
-                                    }
-                                }
-                                unless (@newcoowners > 0) {
-                                    $delcoowners = 1;
-                                    $coowners = '';
+                        } elsif ($coursehash{'internal.co-owners'}) {
+                            foreach my $coowner (split(',',$coursehash{'internal.co-owners'})) {
+                                unless ($coowner eq $uname.':'.$udom) {
+                                    push(@newcoowners,$coowner);
                                 }
                             }
+                            unless (@newcoowners > 0) {
+                                $delcoowners = 1;
+                                $coowners = '';
+                            }
                         }
                         if (@newcoowners || $delcoowners) {
                             &store_coowners($cdom,$cnum,$coursehash{'home'},