FTP Server upload and filesystem questions
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Alex
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Published on 2012-07-04T20:58:28Z
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2012/07/04
21:17 UTC
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I'm a photographer who mainly does event photography. A while ago I bought myself a Nikon WT-4 wireless transmitter, a small device which connects via USB to my Nikon D700 DSLR, and then establishes a WiFi connection to an existing WLAN. It can then upload any pictures I take via FTP to an FTP server somewhere in the network.
On my laptop I then have a piece of software which will check a given folder on the disk regularly, this software is smart enough to look at the modified file timestamp, if this timestamp is less than 10 seconds ago, it will not attempt to import the folder and skip the file in this iteration of the import scan.
The problem I've discovered seems to be inherent to the FTP protocol, as I have the same problem with Windows 7 built in IIS server, as I do with FileZilla FTP server. When the transmitter starts to upload a file, the FTP server will create a small 300-500 KB file with the correct filename on the disk, but then do nothing with the file until it has completely received the file via FTP.
So it seems to create this small dummy file, and then buffer the remainder of the FTP upload until it's finished, and then dump the rest of the file into the dummy file making it the correct size.
Problem is, these uploads take about 15-30 seconds depending on reception, but since the folder watch tool will already try to import any file older than 10 seconds, it will always try to import the small dummy files which obviously fails as they're not copmlete yet.
Is there any way to 'disable' this behaviour? Ideally I would like my file only to show up once it's been completely uploaded. Or perhaps someone knows another FTP server application (it has to run on win7) which does not show this behaviour?
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