PHP: How do I avoid reading partial files that are pushed to me with FTP?

Question

Files are being pushed to my server via FTP. I process them with PHP code in a Drupal module. O/S is Ubuntu and the FTP server is vsftp.

At regular intervals I will

Answer 1

Picking up on the previous answer, you could copy the file over and then compare the sizes of the copied file and the original file at a fixed interval.

If the sizes match, the upload is done, delete the copy, work with the file.

If the sizes do not match, copy the file again.

repeat.