system('djvused',$base_name.'.djvu','-e','select 1; remove-txt','-s');
system('djvused',$base_name.'.djvu','-e','select 1; set-txt '.$base_name.'.txt','-s');
unlink($base_name.'.txt') if -e $base_name.'.txt';
system('djvused',$base_name.'.djvu','-e','select 1; remove-txt','-s');
system('djvused',$base_name.'.djvu','-e','select 1; set-txt '.$base_name.'.txt','-s');
unlink($base_name.'.txt') if -e $base_name.'.txt';