--- loncom/Attic/lchtmldir	2004/10/19 11:11:34	1.10
+++ loncom/Attic/lchtmldir	2004/10/20 09:30:57	1.11
@@ -232,6 +232,13 @@ if($authentication eq "unix:") {	# Unix
     # is that a file system user is being demoted to internal user...
 
     if($authentication eq "internal:") {
+	#  In case the user was a unix/filesystem authenticated user,
+	#  we'll take a bit of time here to write  a script in the
+	#  user's home directory that can reset ownerships and permissions
+	#  back the way the used to be.
+
+	&write_restore_script($homedir);
+
 	&System("/bin/chown -R root:root ".$homedir);
     }
     &System("/bin/chown -R www:www  ".$fulldir);
@@ -371,7 +378,13 @@ sub process_tree {
 
 }
 #
-#  Simple test of process_tree:
+#   Callback from process_tree to write the script lines
+#   requried to restore files to current ownership and permission.
+# Parameters:
+#    dir         - Name of the directory the file lives in.
+#    name        - Name of the file itself.
+#    statinfo    - Array from lstat called on the file.
+#
 #
 sub write_script {
     my ($dir, $name, $statinfo) = @_;
@@ -392,6 +405,46 @@ sub write_script {
 
 
 }
+# 
+#    Write a script in the user's home directory that can restore
+#    the permissions and ownerhips of all the files in the directory
+#    tree to their current ownerships and permissions.  This is done
+#    prior to making the user into an internally authenticated user
+#    in case they were previously file system authenticated and
+#    need to go back.
+#      The file we will create will be of the form
+#        restore_n.sh  Where n is a number that we will keep
+#   incrementing as needed until there isn't a file by that name.
+#   
+# Parameters:
+#    dir      - Path to the user's home directory.
+#
+sub write_restore_script {
+    my ($dir)   = @_;
+
+    #   Create a unique file:
+
+    my $version_number     = 0;
+    my $filename           = 'restore_'.$version_number.'.sh';
+    my $full_name           = $dir.$path_sep.$filename;
+
+    while(-e $full_name) {
+	$version_number++;
+	$filename         = 'restore_'.$version_number.'.sh';
+	$full_name        = $dir.$path_sep.$filename;
+    }
+    # $full_name is the full path of a file that does not yet exist
+    # of the form we want:
+
+    open(CHMODSCRIPT, "> $full_name");
+
+    &process_tree(\&write_script, $dir);
+
+    close(CHMODSCRIPT);
+
+    chmod(0750, $full_name);
+
+}