When iterating over files I must check whether or not the file is available offline if the drive is a virtual drive, for example.
When working with GDrive's "stream files" feature, files in the finder are either considered to be "available offline" or "online only". The very same feature exists for other cloud storage provider such as OneDrive, nextcloud, and dropbox. For my application, checking the state before accessing the file is super important to not trigger an unintentional download of the files through the virtual drive driver.
On windows, things are simple by checking the FILE_ATTRIBUTE_RECALL_ON_DATA_ACCESS and FILE_ATTRIBUTE_RECALL_ON_OPEN file attributes.
On Mac, I fail to find an equivalent but for iCloud. I am checking all kinds of attributes through the NSFileManager attributesOfItemAtPath dictionary as well as the NSURL resourceValues
On OneDrive, it seems to do the trick to simply check if NSURLFileAllocatedSizeKey is zero. GDrive however, seems to cache the data at some place and always reports NSURLFileAllocatedSizeKey to be zero, even though the file is made available offline.
Clearly, there must be a tag / flag / attribute to query from the file system, right?
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I've seen a lot of answers on copying files that use code to set a network share, with credentials, to copy to somewhere else. However I need a solution that will allow a user to copy from a network share they already have access for, to a local drive they don't have access to.
We run RDS servers and have locked down direct access to the local C:/ drive on the servers. We have been given a 3rd party program that needs to read data files that must be stored in a fixed path on the C:/ drive. These data files are updated once a month. Our users have read access but we do not want to give them direct write access to the root C:/ drive.
I need to write a piece of vb.net, or command line code in .bat file that will copy files to the Local C:/ whilst providing the details of a service account to provide the access.
As mentioned I've seen a lot about setting up a mapping to shared folder and passing creds, however we don't want to set the C:/ as mapped shared drive in this instance.
You don't want the user having access to the C Drive in general, is there any particular reason the permissions on the particular subfolder the files are going to can't have overriding permissions to allow writing to just that folder?
If that will not work, first thought that comes to mind is having a helper program that can be ran under a different user that does have that access. Set up an intermediate folder the user can write to, the program that they can launch drops the files into a folder they have access to. Helper program watches for files in the intermediate folder, moves them to where they need to be.
Set up would need to include adding a user that does have access to both locations, and then adding to task manager to launch the helper program under that other user at login.
How can I make sure that a file uploaded through SFTP (in a Linux base system) stays locked during the transfer so an automated system will not read it?
Is there an option on the client side? Or server side?
SFTP protocol supports locking since version 5. See the specification.
You didn't specify, what SFTP server are you using. So I'm assuming the most widespread one, the OpenSSH. The OpenSSH supports SFTP version 3 only, so it does not support locking.
Anyway, even if your server supported file locking, most SFTP clients/libraries won't support SFTP version 5. Or even if they do, they won't support the locking feature. Note that the lock is explicit, the client has to request it.
There are some common workarounds for the problem:
As suggested by #user1717259, you can have the client upload a "done" file, once an upload finishes. Make your automated system wait for the "done" file to appear.
You can have a dedicated "upload" folder and have the client (atomically) move the uploaded file to a "done" folder. Make your automated system look to the "done" folder only.
Have a file naming convention for files being uploaded (".filepart") and have the client (atomically) rename the file after an upload to its final name. Make your automated system ignore the ".filepart" files.
See (my) article Locking files while uploading / Upload to temporary file name for example of implementing this approach.
Also, some SFTP servers have this functionality built-in. For example ProFTPD with its HiddenStores directive (courtesy of #fakedad).
A gross hack is to periodically check for file attributes (size and time) and consider the upload finished, if the attributes have not changed for some time interval.
You can also make use of the fact that some file formats have clear end-of-the-file marker (like XML or ZIP). So you know, when you download an incomplete file.
A typical way of solving this problem is to upload your real file, and then to upload an empty 'done.txt' file.
The automated system should wait for the appearance of the 'done' file before trying to read the real file.
A simple file locking mechanism for SFTP is to first upload a file to a directory (folder) where the read process isn't looking. You can "make" an alternate folder using the sftp> mkdir command. Upload the file to the alternate directory, instead of the ultimate destination directory. Once the SFTP> put command completes, then do a move like this:
SFTP> move alternate_path/filename destination_path/filename. Since the SFTP "move" is just switching the file pointers, it is atomic, so it is an effective lock.
recently I have created a share folder (in windows8) in my organization where everyone has to submit their work. But later I found some one deleting files of others.
From now onward I want keep an eye on the shared folder. Is there any way to save the logs in shared folders. I tried using windows event logs but I am not able to find what I want.Please some one help me.
Windows may log certain authentication events in the Security event-log, however this will only contain useful information if you used local user accounts and gave each person their own local user account (but if you did that, you could prevent them from deleting each others' files).
However Windows does not log SMB share file activity. The Shares list in MMC/Computer Management only lists currently active/open shares too.
All I can suggest is to avoid this from happening in future by either tightening security by creating user-accounts for each person and giving them their own shared directory which only they (and you) have write-access to. Another alternative is to have a program running in the background on your computer that monitors the shared folder for new files and when it detects a file has been placed it moves it away to an inaccessible directory elsewhere.
I am about to install Maverick and before I do that I am going to reformat my macbook air. I use dropbox and have about 15gb of (small) files on it (mainly documents/ebooks).
My question is: Is it possible to backup my Dropbox folder now, reformat my SSD and and install dropbox again. After wish I replace the dropbox folder with my backup without getting Dropbox confused (It might think it are new files? So dropbox could upload them or/and download the same files again).
Does anyone got any experience with this?
It's fine to do this - I have done it myself, but not on OSX.
The Dropbox client will index the files that it finds on your computer and compare them to the ones which are already in your account (on the server). I believe that it uses some kind of hash function to do this - the client creates a small hash value for each file and then this value is compared to the value on the server. If the value is the same then the client assumes that the file is the same and it does not need to be re-uploaded. However, if you have thousands of files, this can take some time.
Source: https://www.dropbox.com/help/1941/en - "The application will index the files and see that they are the same files in your account."
If you want to do it, when you install Dropbox again, you should sign-in to your account, let it create the Dropbox folder and then click "Pause Syncing" so that it doesn't start downloading everything. Then you should copy the backed-up Dropbox files into the new Dropbox folder and resume syncing.
Is there a way to access arbitrary network shared paths and read their content in WinRT? Programatically I want to read from the network shared paths in a WinRT App. I am getting an Access Denied error.
I was told that it might be possible to access the network shared path using file picker provided the app request for permission.
But in my case I do not have access to the file picker. Instead while parsing my model if there is path, I need to read the contents from that path. If that path is network shared path, it fails.
You won't be able to access arbitrary files without the user's explicit permission (via the File Picker).
Some well-known locations like the music and pictures library can be read if the application's manifest includes the associated Declaration, but beyond that all the application can access without the user granting permission (at least once) is its local application data storage.
Have a look at this question: Windows 8 Metro App File Share Access
You may be able to work around this limitation by using a Web Service that has access to the file shares. ;)