--- loncom/auth/lonacc.pm	2000/12/26 19:50:25	1.15
+++ loncom/auth/lonacc.pm	2001/01/06 16:12:24	1.16
@@ -2,7 +2,7 @@
 # Cookie Based Access Handler
 # 5/21/99,5/22,5/29,5/31,6/15,16/11,22/11,
 # 01/06,01/13,05/31,06/01,09/06,09/25,09/28,10/30,11/6,
-# 12/25,12/26 Gerd Kortemeyer
+# 12/25,12/26,06/01 Gerd Kortemeyer
 
 package Apache::lonacc;
 
@@ -11,6 +11,7 @@ use Apache::Constants qw(:common :http :
 use Apache::File;
 use Apache::lonnet;
 use CGI::Cookie();
+use Fcntl qw(:flock);
 
 sub handler {
     my $r = shift;
@@ -29,7 +30,9 @@ sub handler {
             my @profile;
 	    {
              my $idf=Apache::File->new("$lonidsdir/$handle.id");
+             flock($idf,LOCK_SH);
              @profile=<$idf>;
+             $idf->close();
 	    }
             my $envi;
             for ($envi=0;$envi<=$#profile;$envi++) {