it sounds like they are doing security "war games", sounds fun (:

On Sat, Jul 19, 2008 at 8:16 AM, Joe N. <jnardone_at_gmail.com> wrote:

> Garabled Sdjhsjd wrote:
>
>> i can see all the files in the directory. Every dir has a major file to
>> scan. It tells me what the important files are and which are useless + tons
>> of other data to slow me down. Usually there are 25 or less files per
>> directory. When i tell him i started the scan he will wait a few seconds,
>> then move 3 file, wait another few seconds and move another few. a few of
>> the important files are moved/renamed so i miss them. I need to grab them
>> all w/o a rescan. I figure i can make his server stall the move or file
>> rename by a request to DL of the file but not actually read it. Or i could
>> do the transfer very slowly (2k per second? could i go slower?). I think i
>> would need to lock the files for 80 seconds, which is resonable? Can i
>> prevent 24 files from being renamed/moved? How should i lock them? even if i
>> cant do them all a few would be good since i get a better hit ratio
>>
>>
> Far as I know, there is nothing on the client side that you can do to lock
> or otherwise hold files through FTP, SCP, or HTTP; it is entirely up to the
> server (and I've never seen a server that locks the files to prevent them
> from being moved.) There's nothing to stop him from moving files out
> *while* you are transferring them, so a slow rate isn't going to help you at
> all.
> You will need to come up with a mutually agreeable mechanism for locking
> the files at the application level, e.g. you create your own lock file
> before downloading that he respects (and doesn't move files as long as your
> lockfile is present.) It's still a race condition, because he might start
> moving files right before you create the lock file. (Better yet, create a
> lockfile for the directory, which keeps the other program out of this
> directory as long as you are in it.) However, the problem with app-created
> lockfiles is what happens when your app crashes and doesn't remove the lock.
> The other program will never do what it's trying to do (moving the files
> out of the directory.)
>
> This whole design seems pretty convoluted. What is the point of what
> you're trying to do?
>
> joe
>
>
Received on 2008-07-19