PHP - 无法解压缩上传的文件

I'm running 2 simple function:

<?php
    $zipUrl = "path_of_original.zip"
    $zipFilename = "local_path_and_name_of.zip"
    $unzipPath = "destination_of_unzipped_files"

    upload_archive ($zipUrl, $zipFilename);
    unzip_archive ($zipFilename, $unzipPath);
?>

• the 1st, upload a .zip archive on server

  function upload_archive ($zipUrl, $zipFilename){
      define('BUFSIZ', 4095);
      $rfile = fopen($zipUrl, 'r');
      $lfile = fopen($zipFilename, 'w');
  
      while(!feof($rfile))
          fwrite($lfile, fread($rfile, BUFSIZ), BUFSIZ);
  
      fclose($rfile);
      fclose($lfile);}
  

• the 2nd, unzip the archive

  function unzip_archive ($zipFilename, $unzipPath){
      $zip = new ZipArchive;
      $res = $zip->open($zipFilename);
  
      if ($res === TRUE) {
          $zip->extractTo($unzipPath);
          $zip->close();
          echo 'success!';
      } else {
          echo 'error!';
      }
  }
  

when these 2 functions are executed separately everything's fine, but when executed in sequence I can't appreciate the output of the second function (unzip).

I think the problem is that the .zip file is still locked in write by the first function.

any Suggestions?

Angelo.