--- loncom/homework/caparesponse/caparesponse.pm	2010/10/14 19:55:04	1.241
+++ loncom/homework/caparesponse/caparesponse.pm	2010/10/18 19:47:39	1.242
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # caparesponse definition
 #
-# $Id: caparesponse.pm,v 1.241 2010/10/14 19:55:04 raeburn Exp $
+# $Id: caparesponse.pm,v 1.242 2010/10/18 19:47:39 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -1229,11 +1229,27 @@ sub end_stringresponse {
 			${$safeeval->varglob('LONCAPA::CAPAresponse_answer')}=dclone($answer{$name});
 			my ($result, @msgs)=&Apache::run::run("&caparesponse_check_list()",$safeeval);
                         if ($$args_ref{'type'} =~ /^c[si]$/) {
+                            my $control_chars_removed = pop(@msgs);
                             my $error = pop(@msgs);
-                            if ($error ne '') {
+                            if (($error ne '') || 
+                                ($control_chars_removed ne '')) {
                                 my ($symb,$courseid,$domain,$name) =
                                     &Apache::lonnet::whichuser();
-                                &Apache::lonnet::logthis("Stringresponse grading error: $error for $name:$domain in $courseid for part: $part response: $id and symb: $symb");
+                                if ($control_chars_removed ne '') {
+                                    my $showresponse = $response;
+                                    if ($response =~ /[\000-\037]/) {
+                                        $response =~ s/[\000-\037]//g;
+                                    }
+                                    if ($showresponse  =~ /[\r\n\f]/) {
+                                        my @lines = split(/[\r\n\f]+/,$showresponse);
+                                        $showresponse = join('\\n',@lines);
+                                    }
+                                    &Apache::lonnet::logthis("Stringresponse grading: control characters stripped from submission ".$showresponse." for $name:$domain in $courseid for part: $part response: $id and symb: $symb");
+                                    $Apache::lonhomework::results{"resource.$part.$id.submission"} = $response;
+                                }
+                                if ($error ne '') {
+                                    &Apache::lonnet::logthis("Stringresponse grading error: $error for $name:$domain in $courseid for part: $part response: $id and symb: $symb");
+                                }
                             }
                         }
 			&Apache::lonxml::debug('msgs are'.join(':',@msgs));