Hello Experts, 
I am new in Zend Framework, and this code is use for downloading contents.
This code is working in localhost but when i tried to execute in linux server 
it shows error file not found. 
public function downloadAnnouncementsAction() {
            $file= $this-_getParam('file');
        $file = str_replace("%2F","/",$this-_getParam('file'));
    // Allow direct file download (hotlinking)?
    // Empty - allow hotlinking
    // If set to nonempty value (Example: example.com) will only allow downloads when referrer contains this text
    define('ALLOWED_REFERRER', '');
    // Download folder, i.e. folder where you keep all files for download.
    // MUST end with slash (i.e. "/" )
    define('BASE_DIR','file_upload');
    // log downloads?  true/false
    define('LOG_DOWNLOADS',true);
    // log file name
    define('LOG_FILE','downloads.log');
    // Allowed extensions list in format 'extension' => 'mime type'
    // If myme type is set to empty string then script will try to detect mime type
    // itself, which would only work if you have Mimetype or Fileinfo extensions
    // installed on server.
    $allowed_ext = array (        
      // audio
      'mp3' => 'audio/mpeg',
      'wav' => 'audio/x-wav',
      // video
      'mpeg' => 'video/mpeg',
      'mpg' => 'video/mpeg',
      'mpe' => 'video/mpeg',
      'mov' => 'video/quicktime',
      'avi' => 'video/x-msvideo'
    );
    // If hotlinking not allowed then make hackers think there are some server problems
    if (ALLOWED_REFERRER !== ''
    && (!isset($_SERVER['HTTP_REFERER']) || strpos(strtoupper($_SERVER['HTTP_REFERER']),strtoupper(ALLOWED_REFERRER)) === false)
    ) {
      die("Internal server error. Please contact system administrator.");
    }
    // Make sure program execution doesn't time out
    // Set maximum script execution time in seconds (0 means no limit)
    set_time_limit(0);
    if (!isset($file) || empty($file)) {
     die("Please specify file name for download.");
    }
    // Nullbyte hack fix
    if (strpos($file, "\0") !== FALSE)
            die('');
    // Get real file name.
    // Remove any path info to avoid hacking by adding relative path, etc.
    $fname =  basename($file);
    // Check if the file exists
    // Check in subfolders too
    function find_file ($dirname, $fname, &$file_path) {
      $dir = opendir($dirname);
      while ($file = readdir($dir)) {
        if (empty($file_path) && $file != '.' && $file != '..') {
          if (is_dir($dirname.'/'.$file)) {
            find_file($dirname.'/'.$file, $fname, $file_path);
          }
          else {
            if (file_exists($dirname.'/'.$fname)) {
              $file_path = $dirname.'/'.$fname;
              return;
            }
          }
        }
      }
    } // find_file
    // get full file path (including subfolders)
    $file_path = '';
    find_file(BASE_DIR, $fname, $file_path);
    if (!is_file($file_path)) {
      die("File does not exist. Make sure you specified correct file name.");
    }
    // file size in bytes
    $fsize = filesize($file_path);
    // file extension
    $fext = strtolower(substr(strrchr($fname,"."),1));
    // check if allowed extension
    if (!array_key_exists($fext, $allowed_ext)) {
      die("Not allowed file type.");
    }
    // get mime type
    if ($allowed_ext[$fext] == '') {
      $mtype = '';
      // mime type is not set, get from server settings
      if (function_exists('mime_content_type')) {
        $mtype = mime_content_type($file_path);
      }
      else if (function_exists('finfo_file')) {
        $finfo = finfo_open(FILEINFO_MIME); // return mime type
        $mtype = finfo_file($finfo, $file_path);
        finfo_close($finfo);
      }
      if ($mtype == '') {
        $mtype = "application/force-download";
      }
    }
    else {
      // get mime type defined by admin
      $mtype = $allowed_ext[$fext];
    }
    // Browser will try to save file with this filename, regardless original filename.
    // You can override it if needed.
    if (!isset($_GET['fc']) || empty($_GET['fc'])) {
      $asfname = $fname;
    }
    else {
      // remove some bad chars
      $asfname = str_replace(array('"',"'",'\\','/'), '', $_GET['fc']);
      if ($asfname === '') $asfname = 'NoName';
    }
    // set headers
    header("Pragma: public");
    header("Expires: 0");
    header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
    header("Cache-Control: public");
    header("Content-Description: File Transfer");
    header("Content-Type: $mtype");
    header("Content-Disposition: attachment; filename=\"$asfname\"");
    header("Content-Transfer-Encoding: binary");
    header("Content-Length: " . $fsize);
    // download
    // @readfile($file_path);
    $file = @fopen($file_path,"rb");
    if ($file) {
      while(!feof($file)) {
        print(fread($file, 1024*8));
        flush();
        if (connection_status()!=0) {
          @fclose($file);
          die();
        }
      }
      @fclose($file);
    }
    // log downloads
    if (!LOG_DOWNLOADS) die();
    $f = @fopen(LOG_FILE, 'a+');
    if ($f) {
      @fputs($f, date("m.d.Y g:ia")."  ".$_SERVER['REMOTE_ADDR']."  ".$fname."\n");
      @fclose($f);
    }
}
please Help...