title: Objective C - Create text file to read and write line by line in Cocoa
body: <p>I building a Mac app,I have 2 problem:</p>
  
  <blockquote>
    <ol>
    <li>I want to create a text file to read and write data on it. I don't know how to crate a text file to read and write data. Is it use
    struct?</li>
    <li>I want to create a XML file to read and write data on it. Can I create a struct for XML?</li>
    </ol>
  </blockquote>
  
  <p>Do you have suggestion? Thanks in advance</p>