Copy Files coming in a folder over a network in C# - c#-2.0

I receive Files in a Folder at say 2 secs interval from a host machine over " a TCP/IP network" at some Port X. I need to have a service / watcher which will copy these Files to other location. I tried FileSystemWatcher, but it seems that the "Created event" of the watcher gets fired as soon as a byte is getting written to disk.
What is the best way to accomplish this ?

Why not run the copier on a timely basis? Say every 1 minute and copy files.
FileSystemWatcher doesn't seem to be a good option where changes happen more frequently.

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Electron does not run on shared folder

C:\share is shared folder.
C:\share\electron-v13.0.1-win32-x64, \\192.168.1.10\share\electron-v13.0.1-win32-x64 and Z:\electron-v13.0.1-win32-x64 are same folder.
Electron app is launched correctly when I execute C:\share\electron-v13.0.1-win32-x64\electron.exe command.
However, electron app is not launched correctly when I execute Z:\electron-v13.0.1-win32-x64\electron.exe command.
According to the task manager, electron processes are running.
However, electron's window is not shown.
Can electron run correctly on shared folder?
Should be safer to use it locally (from the C:\share). The mapped drives behave very differently compared to local filesystem. And their implementations can differ in their settings as well:
https://wiki.samba.org/index.php/Time_Synchronisation
https://www.truenas.com/community/threads/issue-with-modified-timestamps-on-windows-file-copy.82649/
https://help.2brightsparks.com/support/solutions/articles/43000335953-the-last-modification-date-and-time-are-wrong
If I understand you are just mapping back your own shared folder, and overall the Windows server cofigurations felt to me more consistent, however the protocol changed over the time as well:
https://en.wikipedia.org/wiki/Server_Message_Block
I do not understand the network sharing protocols well to give you exact answer why you have the problem, but I know enough to tell you that the mounted shared folders are not like your own local filesystem. In many cases the differences do not matter and it gives great user expierence, but in some cases these minute differences break things in misterious ways, even if they are mapped/mounted almost like a regular/local drive. This is not exclusive problem to Electron.
And that is a problem with a lot of things through SMB (mainly binaries/tools), the shared folder might be running a different filesystem, different permission and privileges (or run a completely different structure of permissions underneath if it's a completely different filesystem). Remote folders might have issues with inotify getting events on file updates, might miss changed file (like touch on Linux is meant to update date on the file), so through shared folder the date updates might be delayed/rounded. I think at one point even Makefiles were misbehaving as it was depending on the access-date to work the way it would locally.
Other problem with tools is the sharability, can it handle run multiple instances from the same location? Is it saving something into a ./tmp or some other file which could conflict with other user running it at the same time?
Overall with shares I tend to use them for data (and few times had issues with them as well), but have shared remotely applications only if they are known to not cause troubles.

Duplicity: Too many files in target directory

I'm trying to use duply backup which is based on duplicitiy. My problem is that my remote target ("GMX mediacenter" via WebDAV) seems to limit the number of files in one directory to 3000 (which is not documented - only my experience). When this limit is reached backup always stops because of WebDAV response status 507 with reason 'Insufficient Storage'.
I am seeing the following options:
Split the source into several parts. Then I still have to risk to reach the limit of 3000 files in the target directory.
Increase the volume size (--volsize), but this will only delay the problem, too.
Do I have any other good options?
not a development issue! so maybe the wrong place to ask your question.
i'd say change your backend! how will you ever guarantee that your backup will hold less than 3000 files exactly?
there are lot's of cheap/free services out there offering 2GB upward.
..ede/duply.net

grails app deployment without war

I have task to deploy my grails application on remote office. It was far from my current location and it would be waste of time to travelling there to send update.
But I got another problem, we have slow, unreliable and limited quota for internet connection (3rd world country problem). 1 war file is about 55-60 MB.
I also don't want to send my code to them and let them compile and run it.
Could we use SVN/GIT just to send the update of compiled class to them ?
if yes, how to do that ?
If your application is having <Context reloadable="false" /> then
You can simply replace the class files(which are changed) in the location
apache-tomcat/webapps/applicationName/WEB-INF/classes
You could use something like rsync (or robocopy if you're on Windows) to copy to your remote office. That way, for each update, only the changed parts need to be transferred over the network and you should have less data sent. You could rsync the WAR file itself, or a directory which is the WAR file exploded (uncompressed). One might be more efficient with network traffic than the other, but you'd have to test that yourself if you wanted to go that far.
Also, don't forget that Groovy is compiled down to Java class files. So even if they don't have your source code they can decompile the class files and get source out of it (even though it won't be as pretty). This is worth remembering if you have any "secrets" (database password, etc.) in your source code.

Updating EXE file from server…

I need to update my application from a central server.
The application checks always if it is a correct version, against the server installation.
So when it is not, I need it to update itself.
So how can I copy the EXE if it is running? What solution do I have?
I rename the current running exe to MyTempExe.exe, copy the new exe to the correct location (request elevated privileges if necessary) and then run a separate app to restart the main app. On start up I check for MyTempExe.exe delete it if it's there.
The reason I use a separate app for the restart is I don't have a set time frame for the app to close down and need to wait for it to finish whatever it's doing, on shutdown it writes information to disk about its current state that the updated app will use to resume where the old one left off.
I don't know if it's the best solution but it's the one I use.
As you can see by all the answers there is no set way to do this, so I thought I would add the way we have successfully done this.
We never run an application directly from the network.
We run the application from the local machine and have it copy from the network on startup.
We do this using an application launcher. It downloads an XML file that contains CRC and Version Resource Values for the application files. The XML File is created during the deployment process, in a FinalBuilder Script.
The application then compares the XML File to local content, and copies down needed files. Finally we then launch the application in question. This has worked well for deploying an application that serves around 300 local users. Recently we switch from a file copy to an HTTP download as we found problems with remote user disconnecting drives.
We still still build installations (With Innosetup) to get the basic required files deployed.
Package your app with an installer such as Inno. Download and execute the installer. Have the installer search for and kill your app, or instruct the user to close it. The setup will replace your .exe, and if the app can't be killed or the user is non-cooperative, it'll issue a re-start notice.
Download new EXE to TEMP
Create Batch from EXE, content:
taskkill /PID %process id of running EXE%
copy %new EXE% %running EXE%
%EXE%
all values in %...% are placeholders
execute batch from the running EXE
delete batch
I use TMS TWebUpdate myself, for software updates. The advantage is that there a bunch of extra actions you can put into the script, if you need anything other than plain EXE updates.
I have two components at work the application executable itself and a web-service (SOAP) which provides version details and file downloads.
The application calls a method on the SOAP service to ask for the number of files in the project (project is identified by using the application.exename usually).
The soap service gets its info from an INI file, which has entries like:
[ProjectName]
NumberOfFiles=2
File1=myapp.exe;1.0.0.1
File2=mydll.dll;1.0.0.2
You just update this file at the same time as uploading your new files.
The process of updating the application this:
Get number of files available on the web service
For each file, the application asks for the name and version number from the SOAP server.
The application compares this information to its own version info and decides if the file needs updating, building a local list of files that need updating.
For each file that needs updating the application downloads the file to filename.ext.new
Finally, the application renames all filename.ext to filename.ext.old and renames filename.ext.new to filename.ext and then restarts itself. (No real need for an external app to restart your own program).
Note 1, that you may have to ask for elevation to replace files, depending on where you install your files.
Note 2: be kind to your users, think carefully before you force updates on users.
Note 3: You cannot delete a running exe, but you can rename it and then restart the new version.
Edit===
For some reference data files which cannot contain version information resources, you can have entires like File99=MyDataFile;1.1.2011 the 3 elements to the version number indicates to the client that it should check against the file date/stamp.
You could have a separate update executable whose task is to check the server version, download an updated executable if necessary, and then run the local executable.
Or you could have one executable running in two different modes: 1. on startup, check for an update, if there is one, download the executable to a download directory, run it and quit.
2. The new executable would check if it's running from the installation directory, if not, it would copy itself there, overwriting the old version, start the copy from there, and quit.
My way is the other way round: If a new version is online, promt the user to update. If he want's to (or is forced to...) I end the app and start a new exe (updater). this updater loads the update and replaces the old exe (not running). then it starts the new exe. ready. (You can of course replace other files too.) BUT: Using an Installer like InnoSetup gives you more possibilities and doesn't mix up with the regular uninstaller, so it is really better...
You can do this without running another application. Push the updates to the client from the server while running, storing in a temporary directory on the client. When you want to upgrade move all your running files to another temporary directory, move the new files into the original application directory, and just restart the application using the standard executable name on shutdown.
I upgrade client applications running on unattended machines automatically this way.

How do I delete a folder that another process has open?

I created two services. I want to delete a folder, but that folder is used by my first service. When I execute the first service after that I execute the second service it works fine. But when I try to execute both service at the same time it does not work properly.
Actually, the question should have been "What in the application could prevent folder from deletion by other applications".
Possibilities are:
Your service opens some file in that folder and does not close it. Check all files that you are opening in the service, and close the ones which are in that folder.
How files are closed depends on how they were opened. If you used CreateFile(), then close with CloseHandle(). If it was TFileStream, then just Destroy it.
Your service has that folder set as the current directory. Choose other directory as a current with SetCurrentDir.
you cannot delete it unless, you can tell the other service by sending message to stop using the folder(or its content) before deleting it.
If first service is launched before second service then you can delete folder but if both services are launched together then you can't delete folder.
Only difference is you allowed time for first service to finish working with the folder.
Things to consider:
If your first service is using the folder then you won't be able to delete it until your service closes connection with that folder like already mentioned.

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