--- loncom/interface/domainprefs.pm	2017/10/13 20:37:34	1.315
+++ loncom/interface/domainprefs.pm	2017/11/12 19:46:30	1.316
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Handler to set domain-wide configuration settings
 #
-# $Id: domainprefs.pm,v 1.315 2017/10/13 20:37:34 raeburn Exp $
+# $Id: domainprefs.pm,v 1.316 2017/11/12 19:46:30 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -1656,7 +1656,8 @@ sub display_color_options {
                         if ($fullwidth ne '' && $fullheight ne '') {
                             if ($fullwidth > $width && $fullheight > $height) { 
                                 my $size = $width.'x'.$height;
-                                system("convert -sample $size $input $output");
+                                my @args = ('convert','-sample',$size,$input,$output);
+                                system({$args[0]} @args);
                                 $showfile = "/$imgdir/tn-".$filename;
                             }
                         }
@@ -9066,14 +9067,14 @@ sub publishlogo {
     } else {
         my $source = $filepath.'/'.$file;
         my $logfile;
-        if (!open($logfile,">>$source".'.log')) {
+        if (!open($logfile,">>",$source.'.log')) {
             return (&mt('No write permission to Authoring Space'));
         }
         print $logfile
 "\n================= Publish ".localtime()." ================\n".
 $env{'user.name'}.':'.$env{'user.domain'}."\n";
 # Save the file
-        if (!open(FH,'>'.$source)) {
+        if (!open(FH,">",$source)) {
             &Apache::lonnet::logthis('Failed to create '.$source);
             return (&mt('Failed to create file'));
         }
@@ -9134,7 +9135,8 @@ $env{'user.name'}.':'.$env{'user.domain'
                 if ($fullwidth ne '' && $fullheight ne '') { 
                     if ($fullwidth > $thumbwidth && $fullheight > $thumbheight) {
                         my $thumbsize = $thumbwidth.'x'.$thumbheight;
-                        system("convert -sample $thumbsize $inputfile $outfile");
+                        my @args = ('convert','-sample',$thumbsize,$inputfile,$outfile);
+                        system({$args[0]} @args);
                         chmod(0660, $filepath.'/tn-'.$file);
                         if (-e $outfile) {
                             my $copyfile=$targetdir.'/tn-'.$file;
@@ -9214,7 +9216,7 @@ sub write_metadata {
     {
         print $logfile "\nWrite metadata file for ".$targetdir.'/'.$file;
         my $mfh;
-        if (open($mfh,'>'.$targetdir.'/'.$file.'.meta')) {
+        if (open($mfh,">",$targetdir.'/'.$file.'.meta')) {
             foreach (sort(keys(%metadatafields))) {
                 unless ($_=~/\./) {
                     my $unikey=$_;
@@ -9248,7 +9250,7 @@ sub notifysubscribed {
         next unless (ref($targetsource) eq 'ARRAY');
         my ($target,$source)=@{$targetsource};
         if ($source ne '') {
-            if (open(my $logfh,'>>'.$source.'.log')) {
+            if (open(my $logfh,">>",$source.'.log')) {
                 print $logfh "\nCleanup phase: Notifications\n";
                 my @subscribed=&subscribed_hosts($target);
                 foreach my $subhost (@subscribed) {
@@ -9274,7 +9276,7 @@ sub notifysubscribed {
 sub subscribed_hosts {
     my ($target) = @_;
     my @subscribed;
-    if (open(my $fh,"<$target.subscription")) {
+    if (open(my $fh,"<","$target.subscription")) {
         while (my $subline=<$fh>) {
             if ($subline =~ /^($match_lonid):/) {
                 my $host = $1;