How to check if a file is completely written?

Hi
My question relates to polling for a file in a particular directory written by an external process (maybe FTP ...). What I need to know is whether there is a way of determining whether the file has been completely written to the disk by the external process.
I need to find a way so that I do not end up processing partial files in the polling process.
Thanks
Raghu Warrier

My question relates to polling for a file in a
particular directory written by an external processNot particularly, one can implement some type of lock file or even maybe some OS-specific locking mechanisms, but none of which which one would enable/control from within Java. One simple method to dramatically reduce contention time in this manner for most OSs (and to emprically introduce some level of atomicity) is to write to a separate directory on the same filesystem, then once the other process knows the file is complete, then move it to the new directory which generally involved just index pointer addition/moving into the directory entry which is of course much more `atomic' than polling on directory entries themselves.
is a way of determining whether the file has been
completely written to the disk by the external
process. Some OSs don't write the file size until the writing process is done, but this is not guaranteed across OSs. Anyway to introduce a socket semaphore?
I need to find a way so that I do not end up
processing partial files in the polling process.You can also poll the filename->size mappings and with a sufficient poll delta determine if the file is no longer being written. This is not perfect, but a fail-foul solution at that.

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* To change this template, choose Tools | Templates
* and open the template in the editor.
package scoket1;
import java.beans.XMLDecoder;
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END IF;
END;
cheers
Q

How to check if a file is completely written?

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