diff --git a/README.md b/README.md
index 5604baf..d9664ae 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@ A library for using [Avro](http://avro.apache.org/) with PHP.
 
 Requirements
 ------------
- * PHP 5
+ * PHP 5.5.9+
  * On 32-bit platforms, the [GMP PHP extension](http://php.net/gmp)
  * For testing, [PHPUnit](http://www.phpunit.de/)
 
diff --git a/composer.json b/composer.json
index cfab5e9..766f86a 100644
--- a/composer.json
+++ b/composer.json
@@ -31,12 +31,12 @@
     }
   ],
   "require": {
-    "php": ">=5.3.3"
+    "php": ">=5.5.9"
   },
   "require-dev": {
     "jakub-onderka/php-parallel-lint": "0.9.2",
     "jakub-onderka/php-console-highlighter": "0.3.2",
-    "phpunit/phpunit": "^4.0.0"
+    "phpunit/phpunit": "4.8.36"
   },
   "suggest": {
     "ext-gmp": "Large integer support for 32-bit platforms."
diff --git a/lib/avro/datum.php b/lib/avro/datum.php
index fb70760..3a5351f 100644
--- a/lib/avro/datum.php
+++ b/lib/avro/datum.php
@@ -1018,7 +1018,7 @@ public function skip_int() { return $this->skip_long(); }
   protected function skip_long()
   {
     $b = $this->next_byte();
-    while (0 != ($b & 0x80))
+    while (0 != (ord($b) & 0x80))
       $b = $this->next_byte();
   }
 
diff --git a/test/AllTests.php b/test/AllTests.php
index b2be17a..fc4921a 100644
--- a/test/AllTests.php
+++ b/test/AllTests.php
@@ -26,6 +26,7 @@
 require_once('FloatIntEncodingTest.php');
 require_once('DatumIOTest.php');
 require_once('ProtocolFileTest.php');
+require_once('FileIOTest.php');
 // InterOpTest tests are run separately.
 
 /**
@@ -48,6 +49,7 @@ public static function suite()
     $suite->addTestSuite('FloatIntEncodingTest');
     $suite->addTestSuite('DatumIOTest');
     $suite->addTestSuite('ProtocolFileTest');
+    $suite->addTestSuite('FileIOTest');
     return $suite;
   }
 }
diff --git a/test/DataFileTest.php b/test/DataFileTest.php
index 1924d98..da23e9b 100644
--- a/test/DataFileTest.php
+++ b/test/DataFileTest.php
@@ -57,8 +57,7 @@ protected static function remove_data_file($data_file)
 
   protected function remove_data_files()
   {
-    if (self::REMOVE_DATA_FILES
-        && 0 < count($this->data_files))
+    if (self::REMOVE_DATA_FILES && $this->data_files)
       foreach ($this->data_files as $data_file)
         $this->remove_data_file($data_file);
   }
@@ -82,9 +81,9 @@ public function test_write_read_nothing_round_trip()
     $dw->close();
 
     $dr = AvroDataIO::open_file($data_file);
-    $read_data = array_shift($dr->data());
+    $data = $dr->data();
     $dr->close();
-    $this->assertEquals(null, $read_data);
+    $this->assertEmpty($data);
   }
 
   public function test_write_read_null_round_trip()
@@ -97,7 +96,8 @@ public function test_write_read_null_round_trip()
     $dw->close();
 
     $dr = AvroDataIO::open_file($data_file);
-    $read_data = array_shift($dr->data());
+    $read_data = $dr->data();
+    $read_data = reset($read_data);
     $dr->close();
     $this->assertEquals($data, $read_data);
   }
@@ -112,7 +112,8 @@ public function test_write_read_string_round_trip()
     $dw->close();
 
     $dr = AvroDataIO::open_file($data_file);
-    $read_data = array_shift($dr->data());
+    $read_data = $dr->data();
+    $read_data = reset($read_data);
     $dr->close();
     $this->assertEquals($data, $read_data);
   }
@@ -130,7 +131,8 @@ public function test_write_read_round_trip()
     $dw->close();
 
     $dr = AvroDataIO::open_file($data_file);
-    $read_data = array_shift($dr->data());
+    $read_data = $dr->data();
+    $read_data = reset($read_data);
     $dr->close();
     $this->assertEquals($data, $read_data);
 
@@ -146,9 +148,10 @@ public function test_write_read_true_round_trip()
     $dw->close();
 
     $dr = AvroDataIO::open_file($data_file);
-    $read_datum = array_shift($dr->data());
+    $read_data = $dr->data();
+    $read_data = reset($read_data);
     $dr->close();
-    $this->assertEquals($datum, $read_datum);
+    $this->assertEquals($datum, $read_data);
   }
 
   public function test_write_read_false_round_trip()
@@ -161,15 +164,16 @@ public function test_write_read_false_round_trip()
     $dw->close();
 
     $dr = AvroDataIO::open_file($data_file);
-    $read_datum = array_shift($dr->data());
+    $read_data = $dr->data();
+    $read_data = reset($read_data);
     $dr->close();
-    $this->assertEquals($datum, $read_datum);
+    $this->assertEquals($datum, $read_data);
   }
   public function test_write_read_int_array_round_trip()
   {
     $data_file = $this->add_data_file('data-wr-int-ary.avr');
     $writers_schema = '"int"';
-    $data = array(10, 20, 30, 40, 50, 60, 70);
+    $data = array(10, 20, 30, 40, 50, 60, 70, 567, 89012345);
     $dw = AvroDataIO::open_file($data_file, 'w', $writers_schema);
     foreach ($data as $datum)
       $dw->append($datum);
diff --git a/test/FileIOTest.php b/test/FileIOTest.php
new file mode 100644
index 0000000..cb5bd9d
--- /dev/null
+++ b/test/FileIOTest.php
@@ -0,0 +1,95 @@
+<?php
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+require_once('test_helper.php');
+
+/**
+ * Tests against a preexisting file created by a different library
+ */
+class FileIOTest extends PHPUnit_Framework_TestCase
+{
+    protected function tearDown()
+    {
+        $file = $this->getTmpFile();
+        if (file_exists($file))
+            unlink($file);
+    }
+
+    private function getFileName()
+    {
+        return __DIR__ . '/data/users.avro';
+    }
+
+    private function getTmpFile()
+    {
+        return __DIR__ . '/tmp/users.avro';
+    }
+
+    private function read()
+    {
+        $fileName = $this->getFileName();
+        $reader = AvroDataIO::open_file($fileName);
+        return $reader->data();
+    }
+
+    public function testReading()
+    {
+        $expected = [
+            [
+                'name' => 'Alyssa',
+                'favorite_color' => null,
+                'favorite_numbers' => [3, 9, 15, 20],
+            ],
+            [
+                'name' => 'Ben',
+                'favorite_color' => 'red',
+                'favorite_numbers' => [],
+            ]
+        ];
+        $this->assertEquals($expected, $this->read());
+    }
+
+    /**
+     * Doesn't work because due to Avro format peculiarities mean that no two
+     * encodings of the same data will be binary equal.
+     */
+    public function disabled_testRoundTrip()
+    {
+        $inFile = $this->getFileName();
+        $outFile = $this->getTmpFile();
+        $schemaFile = __DIR__ . '/data/user.avsc';
+        $data = $this->read();
+        $schema = file_get_contents($schemaFile);
+        $writer = AvroDataIO::open_file($outFile, 'w', $schema);
+        foreach ($data as $record)
+        {
+            $writer->append($record);
+        }
+        $writer->close();
+
+        $oldData = file_get_contents($inFile);
+        $newData = file_get_contents($outFile);
+        if ($oldData !== $newData)
+        {
+            $diff = shell_exec("bash -c \"diff -y -W 150 <(xxd '$inFile') <(xxd '$outFile')\"");
+            $this->fail("Round trip failed, files not equal:\n$diff");
+        }
+        $this->assertTrue(true, 'Dummy assert to prevent this test from being marked as risky');
+    }
+}
diff --git a/test/SchemaTest.php b/test/SchemaTest.php
index 9a963b8..483177f 100644
--- a/test/SchemaTest.php
+++ b/test/SchemaTest.php
@@ -437,10 +437,6 @@ function test_json_decode()
                         array("bar", "baz", "blurfl"));
     $this->assertFalse(is_array(json_decode('null', true)));
     $this->assertEquals(json_decode('{"type": "null"}', true), array("type" => 'null'));
-    foreach (array('true', 'True', 'TRUE', 'tRue') as $truthy)
-    {
-      $this->assertEquals(json_decode($truthy, true), true, $truthy);
-    }
     $this->assertEquals(json_decode('"boolean"'), 'boolean');
   }
 
diff --git a/test/data/user.avsc b/test/data/user.avsc
new file mode 100644
index 0000000..a396d73
--- /dev/null
+++ b/test/data/user.avsc
@@ -0,0 +1 @@
+{"type": "record", "namespace": "example.avro", "name": "User", "fields": [{"type": "string", "name": "name"}, {"type": ["string", "null"], "name": "favorite_color"}, {"type": {"items": "int", "type": "array"}, "name": "favorite_numbers"}]}
diff --git a/test/data/users.avro b/test/data/users.avro
new file mode 100644
index 0000000..27c526a
Binary files /dev/null and b/test/data/users.avro differ