--- loncom/lonnet/perl/lonnet.pm	2008/04/30 22:42:59	1.957
+++ loncom/lonnet/perl/lonnet.pm	2008/05/12 20:59:15	1.958
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.957 2008/04/30 22:42:59 raeburn Exp $
+# $Id: lonnet.pm,v 1.958 2008/05/12 20:59:15 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -39,7 +39,7 @@ use vars qw(%perlvar %spareid %pr %prp $
 my (%badServerCache, $memcache, %courselogs, %accesshash, %domainrolehash,
     %userrolehash, $processmarker, $dumpcount, %coursedombuf,
     %coursenumbuf, %coursehombuf, %coursedescrbuf, %courseinstcodebuf,
-    %courseownerbuf, %coursetypebuf);
+    %courseownerbuf, %coursetypebuf,$locknum);
 
 use IO::Socket;
 use GDBM_File;
@@ -526,6 +526,51 @@ sub get_env_multiple {
     return(@values);
 }
 
+# ------------------------------------------------------------------- Locking
+
+sub set_lock {
+    my ($text)=@_;
+    $locknum++;
+    my $id=$$.'-'.$locknum;
+    &appenv({'session.locks' => $env{'session.locks'}.','.$id,
+             'session.lock.'.$id => $text});
+    return $id;
+}
+
+sub get_locks {
+    my $num=0;
+    my %texts=();
+    foreach my $lock (split(/\,/,$env{'session.locks'})) {
+       if ($lock=~/\w/) {
+          $num++;
+          $texts{$lock}=$env{'session.lock.'.$lock};
+       }
+   }
+   return ($num,%texts);
+}
+
+sub remove_lock {
+    my ($id)=@_;
+    my $newlocks='';
+    foreach my $lock (split(/\,/,$env{'session.locks'})) {
+       if (($lock=~/\w/) && ($lock ne $id)) {
+          $newlocks.=','.$lock;
+       }
+    }
+    &appenv({'session.locks' => $newlocks});
+    &delenv('session.lock.'.$id);
+}
+
+sub remove_all_locks {
+    my $activelocks=$env{'session.locks'};
+    foreach my $lock (split(/\,/,$env{'session.locks'})) {
+       if ($lock=~/\w/) {
+          &remove_lock($lock);
+       }
+    }
+}
+
+
 # ------------------------------------------ Find out current server userload
 sub userload {
     my $numusers=0;
@@ -8763,6 +8808,7 @@ $memcache=new Cache::Memcached({'servers
 
 $processmarker='_'.time.'_'.$perlvar{'lonHostID'};
 $dumpcount=0;
+$locknum=0;
 
 &logtouch();
 &logthis('<font color="yellow">INFO: Read configuration</font>');