why the code can't update the content in the csv?
$dir   = getcwd();
   $files = scandir($dir);
   foreach ($files as $file)
   {
       $parts = pathinfo($file);
       if($parts['extension']!="csv") continue;
       if (($handle = fopen($file, "r")) !== FALSE)
       {
           $new_content =  implode(',', fgetcsv($handle, 1000, ","))."n";
           while (($data = fgetcsv($handle, 1000, ",")) !== FALSE)
           {
               $data[12]=substr($data[12],9);
               $data[13]=substr($data[13],9);
               $data[14]=substr($data[14],9);
               $data[42]=888;
               $new_content .= implode(',', $data)."n";
           }
           fclose($handle);
        file_put_contents($file, $new_content);
       }
   }

$data = fgetcsv($handle, 0, ','); // >= PHP 5.0.4

$data = fgetcsv($handle, 4096, ',');

$dir   = getcwd();
$files = scandir($dir);
foreach ($files as $file) {
   $parts = pathinfo($file);
   if ($parts['extension']!="csv") {
       continue;
   }
   if (false === ($outfile = fopen("$file.tmp", "w"))) {
       continue;
   }
   if (($handle = fopen($file, "r")) !== FALSE) {
       fputcsv($outfile, fgetcsv($handle, 4096, ","));

       while (($data = fgetcsv($handle, 4096, ",")) !== FALSE) {
           $data[12]=substr($data[12],9);
           $data[13]=substr($data[13],9);
           $data[14]=substr($data[14],9);
           $data[42]=888;
           fputcsv($outfile, $data);
       }
       fclose($handle);
       fclose($outfile);
       if (false === rename("$file.tmp", $file)) {
           die("Could not rename temporary file");
       }
   }
}