Determining when a file has finished copying

[writeson]

Hi all,

I'm writing some code that monitors a directory for the appearance of
files from a workflow. When those files appear I write a command file
to a device that tells the device how to process the file. The
appearance of the command file triggers the device to grab the
original file. My problem is I don't want to write the command file to
the device until the original file from the workflow has been copied
completely. Since these files are large, my program has a good chance
of scanning the directory while they are mid-copy, so I need to
determine which files are finished being copied and which are still
mid-copy.

I haven't seen anything on Google talking about this, and I don't see
an obvious way of doing this using the os.stat() method on the
filepath. Anyone have any ideas about how I might accomplish this?

Thanks in advance!
Doug