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How to programmatically determine which process created a file in .net?

There are several threads on SO that describe how to check which application creates a file with tools like Sysinternals process monitor. Is something like this possible programmatically from .net?
Background: My program has to remote-control a proprietary third party application using its automation interface, and one of the functions I need from this application has a bug where it creates a bunch of temporary files in %TEMP% that are called tmpXXXX.tmp (the same as .net's Path.GetTempFileName() does) but does not delete them. This causes the C drive to become full over time, eventually failing the application. I already filed a bug to the manufacturer, but we need a temporary workaround for the time being, so I thought of putting a FileSystemWatcher on %TEMP% that watches tmp*.tmp, collects these files, and after the operation on the third-party application finishes, deletes them. But this is risky as another application might also write files with the same file name pattern to %TEMP% so I only want to delete those created by NastyBuggyThirdPartyApplication.exe.
Is this anyhow possible?

This kind of things is possible, but maybe a bit tricky.
To know who created the file, look at the user that owns it. Therefore you might need to create a specific user, and that application will run under this specific user. In order to do that, you need to create a small application that will start your buggy app by impersonating another user, so anything done within the app will be under this user so as file creating...
I don't know how to monitor and get triggered when a file is created, but nothing can prevent you from setting a timer that wakes up every five or ten minutes, then checks if any file in the directory is owned by the application user and closed, so it deletes it.
Maybe if they react fast for this bug fixing, you won't need your app very long time. So another solution, if possible might just to change the Temp folder into another drive, which has lots of space...

One solution is that you use a FileWatcher to automatically delete all the files but before deleting you should check if the file is not currently locked or used by other process, for example the Sysinternal Suite has a tool called handle.exe that can do this. Use it from the command line:
handle.exe -a
You can invoke this from a c# program (there might be some performance issues though)
So what you would do is when a file is created you verify if it is in use or locked (for example u can use the code provided in Is there a way to check if a file is in use?) and then delete it.
Most of the time when an app is using a temp file it will lock it to prevent just what you fear, that you might delete files from other processes.
As far as I can tell there is no sure way to identify which process created a specific file.

Refresh start menu icons in Windows 8

I have an application that works weirdly: the setup process copies the files to a temp folder, then checks a few things, and if everything is ok, moves the files to the final folder.
The problem is that the installer creates the shortcuts before the files are moved.
The result is that on the start menu (the one with the tiles), the icon is the "default sortcut" one.
I have tried to force the refresh of the system using this link (broadcast a WM_SETTINGCHANGE message) but it doesn't seem to work for the Windows 8 start menu.
Even rebooting the OS doesn't seem to refresh the icon, the only thing that works is to reinstall the soft on top of itself.
How can I force the icons refresh for the Win8 start menu ?
Thanks

First off, you don't tell us why your install process needs to work the way that it does. I agree that's weird, but I assume you have a good reason for doing it that way. If not, I suggest starting there and fixing the installer rather than putting band-aids on individual problems. You're bound to run into other problems later, and the root fix is bound to be much simpler and easier to maintain than a bunch of band-aids.
Anyway, if you must go down this path… The reason that broadcasting a WM_SETTINGCHANGE message doesn't work is because this doesn't have anything to do with icons. Those are managed separately by Explorer and don't get rebuilt unless you delete its icon cache. That, naturally, prompts it to rebuild it. It's a common troubleshooting technique for end users, but it's not something you want to do programmatically. Talk about an ugly hack. And altering the global state to solve a local problem.
Besides, if rebooting the OS doesn't work, you know it's not as simple as you make it sound in your question: a property in need of a refresh. The reason that reinstalling on top of the existing installation works is because when the shortcut gets created in the beginning, its target executable already exists in the expected place (put there by the previous installation) with a valid icon.
What I recommend doing is writing some code to change the icon of the existing shortcut. Make sure that you execute it after you've copied the executable file to its final destination. The method that allows you to do that is IShellLink::SetIconLocation, which takes two parameters: a path to the icon (this would be the path to your executable file), and the index of the icon (this would probably be 0 assuming that the icon you want is the first and only one contained in the executable).
Of course, in order to call SetIconLocation, you're going to have to obtain an object representing your shortcut that implements IShellLink. This is a COM interface, which I don't believe is wrapped anywhere by the .NET Framework. General information on creating shortcuts from C# is available in the answers to this question. More specifically, there's a link to this wrapper class that you can use to do most of the dirty work. I don't think it contains a method for setting/changing the icon, but that can be trivially added.
Alternatively, you can get at these same properties using the Windows Scripting Host (WSH) wrapper, WshShortcut. It has an IconLocation property that works much the same way except that it takes only a single string argument, with the index delimited from the path by a comma: myApp.exe, 0. It's not particularly well documented (best I can find), but to get an existing shortcut, you just use the CreateShortcut method and specify the path to the existing shortcut. For example:
public void SetShortcutIcon(string shortcutPath, string iconPath, int iconIndex)
{
// Note: no error checking is performed for the parameters!
// This is not production-ready code!
// If a shortcut does not exist at the specified path, you should
// create a new one instead.
// If iconPath does not specify a valid executable file, you should
// set a default icon or perhaps abort.
IWshRuntimeLibrary.WshShell wsh = new IWshRuntimeLibrary.WshShell();
IWshRuntimeLibrary.IWshShortcut shortcut = wsh.CreateShortcut(shortcutPath);
shortcut.IconLocation = String.Format("{0}, {1}", iconPath, iconIndex);
shortcut.Save();
}
Note that in order for the above code to compile, you will also need to add a reference to the Windows Script Host Object Model to your application. To do this, right-click on the "References" folder in the Solution Explorer, click the "COM" tab, and find "Windows Script Host Object Model" in the list.
I just tested this and it works; the effect is instant.

Use PolicyKit to give my application access to restricted files

I'm writing an application for Ubuntu, which allows you to customize the Unity 2D desktop environment.
Some settings, I can change using Dconf, which is user-specific. So if one user changes a setting, it only applies for that user.
For other settings, however, I need to edit text files which are located in /usr/share/unity-2d/, to which a normal user can't write. To solve this problem, I thought it was a good idea to have users run the application as root, which makes sure they have access to /usr/share/unity-2d/. Only, when the application is running as root, and one of the Dconf settings is changed, it gets changed in the root user's Dconf, so the changes don't apply to the actual user.
I need to find a solution to this problem, and my first realistic idea was to use PolicyKit. I need to make sure that my application runs as the current user (so not always as root), but that it does have access to /usr/share/unity-2d/ and the files inside it. I'm writing the application in C#, using the Mono framework. I don't really have any experience with PolicyKit, and to be honest this is my first attempt in making a serious Linux application.
My idea was PolicyKit, but if one of you has another (realistic) way to achieve this, that fine with me as well. If it comes down to using PolicyKit, I'd like to have a bit more information on how to do this, and what everything does, please. I know I can probably just run my application using pkexec, but I was actually thinking more among the lines of a button in my application to unlock the features which need access to that directory, which at that moment asks for a password to get writing access to the files in the folder. In this way, people who don't have special permissions on the system the application is running on, can still customize some basic settings.

Well, the obvious solution is to have two processes, one normal user app with the GUI, and something that runs as root that manipulates files as root.
E.g. as an analog "commandline only" issue would writing a file as root:
sudo echo Hello World >/root/hello.txt
Does not work because the redirection is done by the interactive shell and it does not have root's access.
The classical solution is to use two processes:
echo Hello World | sudo tee /root/hello.txt
Now the /root/hello.txt file is opened by tee which runs as root (via sudo), which is allowed.

Rename a running executable (exe) file [duplicate]

This question already has answers here:
Why does rename a loaded .net assembly work?
(3 answers)
Closed 5 years ago.
We are trying to push updates to multiple servers at once and my manager has found that it is possible to rename running .exe file. Using that knowledge he wants to rename a running exe and copy over a new version of said exe such that anyone running their in memory copy of foo.exe are fine and anybody who opens a shortcut pointing to foo.exe will get a new copy with updates applied.
I guess I need to clarify, He doesn't expect the old copy to magically update, he just expects them to keep running the old copy until they open the exe again, in which case it will then open the new one that has the name of the old one.
It sometimes throws an exception that the file is in use on his program but if he tries renaming it in a loop it will eventually succeed. On my machine I have yet to be able to get it to work even in a loop.
My first and main question is this: Is it ever acceptable to do this. Should renaming a running executable ever be a valid scenario?
Secondly, if it is a valid scenario then how could one reliably do this? Our current thoughts are try a bunch of times using File.Move (C#) to do a rename and if it doesn't work then write out to an error log so it can be handled manually.

An airplane mechanic and a surgeon meet in a bar. The mechanic says "you know, we have basically the same job. We take broken stuff out and put new, better parts in." The surgeon says "yeah, but you don't have to keep the plane flying as you're making the repairs!"
Trying to update an application by moving files while the application is running seems about as dangerous as trying to fix an airplane in flight. Possible? Sure. Greatly increased risk of catestrophic crash? Yep.
If the application you are updating is a managed application, consider using ClickOnce Deployment. That way, the next time someone runs the application, if there is a new version available it will be copied down and installed automatically. That's much more safe and pleasant than trying to mess with an application while its still running.

No, this is not acceptable. Do not do this. This is not a valid deployment mechanism. This should have been yours or his first clue:
It sometimes throws an exception that the file is in use on his program but if he tries renaming it in a loop it will eventually succeed.
And it won't work, anyway. His theory is quite wrong:
Using that knowledge he wants to rename a running exe and copy over a new version of said exe such that anyone running their in memory copy of foo.exe are fine and anybody who opens a shortcut pointing to foo.exe will get a new copy with updates applied.
Specifically, the copy in memory will not be automatically replaced with the new executable just because it has the same name. The reason that you're allowed to rename the executable in the first place is because the operating system is not using the file name to find the application. The original executable will still be loaded, and it will remain loaded until you explicitly unload it and load the new, modified executable.
Notice how even modern web browsers like Chrome and Firefox with their super fancy automatic, in the background, no one ever notices that they exist, updaters still have to close and relaunch the application in order to apply the updates.
Don't worry about shooting the messenger here. It's more likely that your customers and your tech support department will shoot you first.
See number 1.

In our organization, we solved the problem of Updates by having two release folders say EXE_A and EXE_B. We also have a release folder called EXE which only has links ALL of which points to either to EXE_A or EXE_B from which the user runs the applications.
When we publish a new version of the program, we publish it to the folder that is not referenced in the links and then update the links (EXE). In this way, you do not get into exceptions that users are holding the application / assemblies. Also if a user wants to run the updated version, all he need to do is close / re-execute the link in EXE folder.

If you use Windows Vista/Server2k8 or newer you could use mklink to create a symbolic link to the folder containing your application and start the application out of the "symblic linked folder" and then at the update create a new folder, e.g. "AppV2" and change the SymLink to that folder, so the next time the user restarts the application he starts it out of the new folder without noticing.
Renaming open files is ALWAYS a bad choice!
But in general I would think of a better deployment strategy anyway, because if you need to use such "hacks" it is always a messy situation. I don't know your application, but maybee ClickOnce would be a point to start, because you can configure it to check for updates on every start...

How to get the installation directory (installed with MSI, created with VS2010) at a custom uninstall action?

So I've created a simple msi-setup for my application using a setup project and added a couple of custom actions that take care of stuff like extracting files from archives. Now, there are two extra files in my program files -directory which means that the MSI won't remove the directory at the uninstall by itself. My solution to this was to create a custom action that removes the rest of the files.
Now this works just fine and dandy, as long as the default directory is used at installation. But what if the user chooses to change it? I'd assume there has to be a very simple way to read the directory at the custom action, but I'm not quite sure what that is.
As far as I've found out by googling, there are properties such as TARGETDIR related to the MSI-package. However, some sites also say that I should be setting this property by myself, at the installation stage.
All this has left me quite confused. Basically I see two ways to resolve this:
1) Make sure the application does not create files by itself, and the MSI will take care of it. This would mean a bit more work because I'm not responsible for those extra files.
2) Find out the installation directory at the custom action while uninstalling the application, and remove the last bits by myself. This is the quick-and-dirty way as I see it, and would definitely suffice for now. But how to accomplish this?
Also while I'm here I might as well ask this one more related question. As I mentioned earlier, I extract some files at the install. Now, I'd like to get rid of these archives once I've extracted them. The problem is, if I do this, MSI will think my installation is broken and copy them back each time I launch the application. So how to avoid this?

There is no need to use a custom action to remove the files. MSI has built in support for this scenario in two steps:
Use a search to locate the files you want to remove. Here is a tutorial
http://msdn.microsoft.com/en-us/library/aa371564(VS.85).aspx
Then you can schedule a file removal operation to actually delete the files.
http://msdn.microsoft.com/en-us/library/aa371201(VS.85).aspx
Regarding your second question:
Don't add the archives to the File table. Instead create some self extracting archives and use binary custom actions to unpack them.
http://msdn.microsoft.com/en-us/library/aa368085(VS.85).aspx