I just had a quick look at dropbox with ProcMon, and I learned that
1) when I created a new text file on my desktop, it was not read by Dropbox
2) when I created a new text file in my dropbox folder, it was immideately read by Dropbox
3) I have to find some sync tool that doesn't feel the need to enumerate my network interfaces 3 times every second, when nothing is actually changing.
Just some more information:
Dropbox does not read the file outside the dropbox folder.
It does, however, 'QueryBasicFileInformation' and and 'QueryDirectory' when I create a file on my desktop.
I'm guessing this has to do with the explorer extension.
This is the first comment in this discussion I've seen that is actually interesting and might provide an explanation.
The Dropbox file status symbols are a -big hack-. Up until OS X 10.10, for instance, the file browsing interface didn't provide per-file badging at the OS API level. So they literally had to patch the running Finder process to do this.
I wouldn't be surprised to learn something similar is going on with Windows Explorer.
I know my company has had many problems that were pinned down to Dropbox hooking some Win32 API functions that we use. I am not familiar with the semantics of hooking, but could it be related to that?
Have you heard/tried Bittorrent sync? It's P2P, doesn't put your files on their server. Very fast for transferring locally between your phone and computer for example. You have to keep your computer running if you want your files accesible anytime though.
Unfortunately btsync is very much not open-source. There are alternatives, though. I am very satisfied with syncthing[1], although it didn't have usable mobile app last time I checked.
And requires port forwarding, which may not be an option for people who are not on IPv4 at home (e.g. my ISP uses DS-Lite, so I cannot use IPv4 port forwarding).
Bittorrent Sync works pretty good. Somebody should reverse engineer the protocol and make an open source client.
Edit: why the heck is the grandparent downvoted? He/she offers a good suggestion.
