--- doc/help/course_manual/buildTexxml.pl	2006/12/01 23:41:33	1.1
+++ doc/help/course_manual/buildTexxml.pl	2006/12/04 18:12:22	1.2
@@ -1,35 +1,44 @@
 #!/usr/bin/perl
+use strict;
 
 if ($#ARGV != 0) {
-  print "Correct command usage: \n";
-  print "   perl buildTexxml.pl all\n";
-  print "Or \n";
-  print "   perl buildTexxml.pl section\n";
+    print("Correct command usage: \n");
+    print("   perl buildTexxml.pl all\n");
+    print("Or \n");
+    print("   perl buildTexxml.pl section\n");
 }
 
-$option = $ARGV[0]; 
+my $option = $ARGV[0]; 
 
-@section = `cat section_order.txt`;
-chomp @section;
+my @section = `cat section_order.txt`;
+chomp(@section);
 
-if($option eq 'all') {
-  foreach $section (@section) {
-    $section='sections/'.$section;
-    $section_list=$section_list.$section.' ';
-  }
-  `cat sections/start.texxml $section_list sections/end.texxml > course.manual.texxml`;
+if ($option eq 'all') {
+    my $section_list;
+    foreach my $section (@section) {
+	$section_list .= 'sections/'.$section.' ';
+    }
+    system("cat sections/start.texxml $section_list sections/end.texxml > course.manual.texxml");
 }
 
-if($option eq 'section') {
-  print "Choose from the following manual sections:\n";
-  $num=0;
-  foreach $section (@section) {
-    print "$num - $section\n";
-    $num++;
-  }
-  print "Enter a number 0 - $num for the section you want to print: ";
-  $selection=<STDIN>;
-  print "builing section...\n";
-  `cat sections/start.texxml sections/$section[$selection] sections/end.texxml > section.manual.texxml`; 
+if ($option eq 'section') {
+    print("Choose from the following manual sections:\n");
+    my $num=0;
+    foreach my $section (@section) {
+	print("$num - $section\n");
+	$num++;
+    }
+    $num--;
+
+    print("Enter a number 0 - $num for the section you want to print: ");
+    my $selection=<STDIN>;
+    chomp($selection);
+
+    if ($selection < 0 || $selection > $#section) {
+	print("Invalid selection ($selection)\n");
+	exit(1);
+    }
+    print("builing section $section[$selection]\n");
+    system("cat sections/start.texxml sections/$section[$selection] sections/end.texxml > section.manual.texxml"); 
 }