// Here My assumption is that $form_state['values']['script_file_upload'] returns the fid
 $file_object = file_load($form_state['values']['script_file_upload']);
 $destination = 'public://abc/' ;
 if(file_prepare_directory($destination, FILE_CREATE_DIRECTORY)) {
   $file = file_move($file_object, $destination . $file_object->filename, FILE_EXISTS_REPLACE);
 }
 if ($file) {
     $file->status = FILE_STATUS_PERMANENT;
     drupal_chmod($file->uri, 0775);
     $file = file_save($file);
}