file locking in ftp
please help me out in this problem.
My client will upload files through ftp .The ftp server is running on linux. I have a script written in VB running on windows which will run every 10 min. and download files through ftp which were uploaded by the client. The problem is that if the client has uploaded only half the file (say 5 MB out of 10 MB) and the script starts downloading at this movement, then only half the file will be downloaded. What i am looking for is a way through which i can lock the file while it is being uploaded so that the script is not able to download it until it is fully uploaded.