title: Command SED in PHP
body: <p>How can I do search and replace in a file with the sed command, since I'm currently getting an error.</p>
  
  <pre><code>$command = "sed -i \"y/\xE1\xE9\xED\xF3\xFA\xF1\xC1\xC9\xCD\xD3\xDA\xD1/aeiounAEIOUN/\" file.txt";
  
  exec($command);
  </code></pre>
  
  <p>I have a .php file from which I execute the previously mentioned command where I intend to eliminate special characters from a .txt file but when doing php script.php I get that error:</p>
  
  <blockquote>
    <p>sed: -e expression #1, char 1: unknown command: `"'</p>
  </blockquote>
  
  <p>Suggestions?</p>