Convert rn to n, can be Global Search & Replace

<?php
/*
////////////////////////////////////////
File : rnton.php
Description: Traverses through a specified
             directory and converts all
             occurances of rn to n,
             in the specified type of
             files.
Why? :       We developed this since after
             changing to the new version of
             PhpEditor, most of our files
             on the Linux machine were
             showing double line spacing :)
Version:     1.0
Date:        April 26, 2001
By:          Nirav Mehta
             [email protected]
             http://www.magnet-i.com
////////////////////////////////////////
*/

if ($startingPath == "")
{
 echo "<h1>Please enter the path to start work from</h1>";
 echo "<form><pre>
       Starting Linux Path: <input type='text' name='startingPath' size='20'>
                            <input type='checkbox' name='recurse' value='1'>Recurse into directories?
                            <input type='submit'>
Note: The files in the directories would have to be chmod 777 to be written back.
      The directories would have to be chmod 755 to be read.
       </pre>
       </form>
       ";
}
else
{
 $ListFormats = array ("php","php3","htm","html");
 function GetFiles($dir)
 {
  GLOBAL $FileList,$ListFormats,$recurse;
  if (!is_dir($dir))
  {
   echo "$dir is not a directory.<br>";
   return $ListFormats;
  }
  echo "-> trying $dir<br>";

  $hDirectory = opendir($dir);
  if ($hDirectory)
  {
   /* Read this directory.*/
   while ( $strFileName = @readdir($hDirectory) )
   {
    /* Check for . or .. */
    if ( $strFileName != '.' && $strFileName != '..' )
    {
     $fullName = $dir . '/' . $strFileName;
     if (is_dir($fullName) && $recurse == 1)
     {
       $FileListSubDir[] = GetFiles($fullName);  // This is recursion... be carefull
       foreach($FileListSubDir as $value)
        $FileList[] = $value;
       unset($FileListSubDir);
     }
     /* Walk list of file format extensions.*/
     while ( list($strIndex, $strExtension) = each($ListFormats) )
     {
      /* Prepend period.*/
      $strExtension = '.' . $strExtension;
      $nExtensionLength = strlen($strExtension);
      /* Is this a valid file? If yes, add to list.*/
      if (strlen($strFileName) > $nExtensionLength
          && strtolower(substr($strFileName, -$nExtensionLength)) == $strExtension
          && is_file($fullName))
      {
       $FileList[] = $fullName;
      }
     }
    reset($ListFormats);
    }
   }
   /* Close the directory now.*/
   closedir($hDirectory);
  }
  return $FileList;
 }

 function convertRNtoN($fileName)
 {
  // get contents of the file into a string
  $fd = fopen ($fileName, "r");
  $contents = fread ($fd, filesize ($fileName));
  fclose ($fd);
  // Find & Replace the rn with n
  if (ereg("rn",$contents))
  {
   echo ".........Found Carriage Return in $fileName<br>";
   $contents = ereg_replace("rn","n",$contents);
   $save = 1;
  }
  else
   $save = 0;
  if ($save)
  {
   $fd = fopen ($fileName, "w");
   @flock($fd,"LOCK_EX"); // lock file
   @fwrite ($fd,$contents); // write to file
   @flock($fd,"LOCK_UN"); // release lock
   fclose ($fd);
   echo ".........Replaced with New Line in $fileName<br>";
  }
  return true;
 }

 // Let's call the function and get the list of the files
 // First let's remove the trailing slash
 if (substr($startingPath,strlen($startingPath)-1,1) == "/")
  $startingPath = substr($startingPath,0,strlen($startingPath)-1);

 $AllFile = GetFiles($startingPath);
 if (is_array($AllFile))
 {
  foreach ($AllFile as $fileName)
  {
   if (!is_array($fileName) && $fileName != "")
   {
     convertRNtoN($fileName);
   }
  }
 }
 else
  echo "No files found. $AllFile";
}
?>