anchor.diff:    static int testCloseExceptionStream() {
       bool exceptionCaught = false;
       bool wrongExceptionCaught = false;
  -    String filename = getFilename("tests/vm/data/fixed_length_file");
  -    File file = new File(filename + "_out_close_exception_stream");
  +    File file = new File(tempDirectory.path + "/out_close_exception_stream");
       file.createSync();
       FileInputStream input = file.openInputStream();
       input.close();
  
positive.code: 
  
  class FileTest {
    // Test for file read functionality.
    static int testReadStream() {
      // Read a file and check part of it's contents.
  
negative.code:   static int testBufferOutOfBoundsException() {
      bool exceptionCaught = false;
      bool wrongExceptionCaught = false;
      File file = new File(tempDirectory.path + "/out_buffer_out_of_bounds");
      file.openSync(true);
      try {
        List<int> buffer = new List<int>(10);
  