--- a/addressbook.class.php	Wed Oct 26 00:15:59 2011 +0200
+++ b/addressbook.class.php	Wed Oct 26 00:37:13 2011 +0200
@@ -1,10 +1,13 @@
 <?
+
 interface Address_Book {
     public function get_entries();
     public function search_entries($pattern);
     public function add_entry($entry);
 }
 
+class Address_Book_Exception extends Exception { }
+
 class Address_Book_File implements Address_Book {
 
     const RS = "\n";
@@ -15,7 +18,8 @@
 
     function __construct($file) {
 	@mkdir(dirname($file));
-	$this->fh = fopen($file, "a+b");
+	@$this->fh = fopen($file, "a+b");
+	if (!$this->fh) throw new Address_Book_Exception("Can't open address book.");
 	flock($this->fh, LOCK_EX);
 	$stat = fstat($this->fh);
 	if ($stat['size'] == 0) {

--- a/index.php	Wed Oct 26 00:15:59 2011 +0200
+++ b/index.php	Wed Oct 26 00:37:13 2011 +0200
@@ -8,36 +8,50 @@
 
 if (isset($_REQUEST['action'])) {
     require 'addressbook.class.php';
-    $abook = new Address_Book_File(FILE);
 
-    switch (@$_REQUEST['action']) {
-	    // Nach dem Eintragen bleiben wir auf der Eintragsseite,
-	    // aber wir verhindern Duplikate, die mit RELOAD passieren
-	    case 'add':	if ($abook->add_entry($_REQUEST)) {
-				header("Location: $_SERVER[PHP_SELF]?action=add");
-				exit(0);
-			}
-			echo $twig->render("add.html", array());
-			exit;
-			break;
+    try {
+	$abook = new Address_Book_File(FILE);
 
-	    // Suchen…
-	    case 'search':  $entries = $abook->search_entries($_REQUEST['pattern']);
-			    if (@$_REQUEST['format'] == 'table') {
-				if (is_numeric($_REQUEST['max'])) {
-				    $left = count($entries) - $_REQUEST['max'];
-				    if ($left > 0) 
-					$entries = array_slice($entries, 0, $_REQUEST['max']);
-				    else
-					$left = NULL;
-				}
-				echo $twig->render("results.html",
-				    array('entries' => $entries, 'left' => $left));
-				exit;
+	switch (@$_REQUEST['action']) {
+		// Nach dem Eintragen bleiben wir auf der Eintragsseite,
+		// aber wir verhindern Duplikate, die mit RELOAD passieren
+		case 'add':	if ($abook->add_entry($_REQUEST)) {
+				    header("Location: $_SERVER[PHP_SELF]?action=add");
+				    exit(0);
 			    }
-			    echo $twig->render("search.html", array('entries' => $entries));
+			    echo $twig->render("add.html", array());
 			    exit;
 			    break;
+
+		// Suchen…
+		case 'search':  $entries = $abook->search_entries($_REQUEST['pattern']);
+				if (@$_REQUEST['format'] == 'table') {
+				    if (is_numeric($_REQUEST['max'])) {
+					$left = count($entries) - $_REQUEST['max'];
+					if ($left > 0) 
+					    $entries = array_slice($entries, 0, $_REQUEST['max']);
+					else
+					    $left = NULL;
+				    }
+				    echo $twig->render("results.html",
+					array('entries' => $entries, 'left' => $left));
+				    exit;
+				}
+				echo $twig->render("search.html", array('entries' => $entries));
+				exit;
+				break;
+	}
+
+    }
+    catch (Address_Book_Exception $e) {
+	header("Content-Type: text/plain; charset=utf-8");
+	print "Address Book Exception: " . $e->getMessage();
+	exit;
+    }
+    catch (Exception $e) {
+	header("Content-Type: text/plain; charset=utf-8");
+	print "Ohoh\n\n" .$e->getMessage();
+	exit;
     }
 }