--- loncom/lonnet/perl/lonnet.pm	2012/04/25 21:22:15	1.1166
+++ loncom/lonnet/perl/lonnet.pm	2012/05/16 21:19:33	1.1167
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.1166 2012/04/25 21:22:15 raeburn Exp $
+# $Id: lonnet.pm,v 1.1167 2012/05/16 21:19:33 droeschl Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -97,6 +97,7 @@ use File::MMagic;
 use LONCAPA qw(:DEFAULT :match);
 use LONCAPA::Configuration;
 use LONCAPA::lonmetadata;
+use LONCAPA::Lond;
 
 use File::Copy;
 
@@ -5071,6 +5072,7 @@ sub dump {
     if (!$udomain) { $udomain=$env{'user.domain'}; }
     if (!$uname) { $uname=$env{'user.name'}; }
     my $uhome=&homeserver($uname,$udomain);
+
     if ($regexp) {
 	$regexp=&escape($regexp);
     } else {
@@ -8099,13 +8101,16 @@ sub generate_coursenum {
 }
 
 sub is_course {
-    my ($cdom,$cnum) = @_;
-    my %courses = &courseiddump($cdom,'.',1,'.','.',$cnum,undef,
-				undef,'.');
-    if (exists($courses{$cdom.'_'.$cnum})) {
-        return 1;
-    }
-    return 0;
+    my ($cdom, $cnum) = scalar(@_) == 1 ? 
+         ($_[0] =~ /^($match_domain)_($match_courseid)$/)  :  @_;
+
+    return unless $cdom and $cnum;
+
+    my %courses = &courseiddump($cdom, '.', 1, '.', '.', $cnum, undef, undef,
+        '.');
+
+    return unless exists($courses{$cdom.'_'.$cnum});
+    return wantarray ? ($cdom, $cnum) : $cdom.'_'.$cnum;
 }
 
 sub store_userdata {
@@ -11976,6 +11981,19 @@ createcourse($udom,$description,$url,$co
 
 generate_coursenum($udom,$crstype) : get a unique (unused) course number in domain $udom for course type $crstype (Course or Community).
 
+=item *
+
+is_course($courseid), is_course($cdom, $cnum)
+
+Accepts either a combined $courseid (in the form of domain_courseid) or the
+two component version $cdom, $cnum. It checks if the specified course exists.
+
+Returns:
+    undef if the course doesn't exist, otherwise
+    in scalar context the combined courseid.
+    in list context the two components of the course identifier, domain and 
+    courseid.    
+
 =back
 
 =head2 Resource Subroutines