title: Trying to create and write to file using NSFileHandle... and it doesn't seem to be working
body: <p>What am I doing wrong here:</p>
  
  <pre><code>NSArray *paths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES);
  NSString *documentsDirectory = [paths objectAtIndex:0]; 
  self.gpsFilePath = [documentsDirectory stringByAppendingString: @"/gpsReadings.txt"];
  self.gpsFile = [NSFileHandle fileHandleForWritingAtPath:self.gpsFilePath];
  [self.gpsFile writeData:@"GPS Readings"];
  [self.gpsFile closeFile];
  </code></pre>