I am trying to create a new file and write XML to it:
FileStream output = File.Create(Path.Combine(PATH_TO_DATA_DIR, fileName));
The argument evaluates to:
C:\path\to\Data\test.xml
The exception is:
The process cannot access the file 'C:\path\to\Data\test.xml' because it is being used by another process.
What am I doing wrong here?
UPDATE: This code throws the same exception:
StreamWriter writer = new StreamWriter(Path.Combine(PATH_TO_DATA_DIR, fileName));
UPDATE 2: The file I am trying to create does not exist in the file system. So how can be it in use?
UPDATE 3: Changed to a new file name, and now it works. I'm not sure why. Perhaps I unknowing created it in the first call, and it failed on subsequent calls?
The message means that another process is using that file. If you have it open it could be using it, or when it was originally created if the stream was not closed properly that could do it also.
First check to make sure you do not have it open. I would try to change the fileName and see if you get the same error. If you do get the same error than some place in your code it is not closing a stream that when it is done with the file.
Your program keeps a handle on your file after it's being created to return to your FileStream object. Because you don't specify the access to it, perhaps it won't let you get a grab on it. Perhaps should you consider closing it, and then reopen it in a proper manner by specifying how you want it open (ReadOnly, ReadWrite, WriteOnly) ?
Not trying to sound insulting, but does the folder exist? Does the file already exist but is hidden by the system? And does the user account that is running the program have write permissions to the folder? Have you tried creating a file using a different method (like with File.WriteAllText(<path>, "Testing") just to see if it's your particular call to File.Create?
Related
I'm trying to use the following code to delete a read-only file.
var fileInfo = new FileInfo(saveLocation);
fileInfo.IsReadOnly = false;
fileInfo.Delete();
When it gets to the third line, the following exception is thrown
Message: The process cannot access the file '\\filepath\filename.pdf' because it is being used by another process.
Note: \\filepath\filename.pdf is not the actual file path, I'm just using it to replace a longer path
I've checked the file, and before the code runs, it is set to read-only, and after the code runs, it is not anymore.
Am I incorrect in thinking that when a file is opened as read-only it is not considered to by in use? I'm pretty sure that is true for Microsoft office files suck as .xlsx files, but maybe not for PDFs?
Ultimately, my goal is to be able to push an updated version of this file to a shared location even if some user has the file open on their machine, which is why I initially set it to be read-only.
Message: The process cannot access the file '\filepath\filename.pdf' because it is being used by another process.
This is not the same as the file being read-only.
You can find out in code which process is locking the file
https://stackoverflow.com/a/20623311/141172
You can also find out from the command line
UPDATE
Based on your comments, it seems like you may want an exclusive lock on the file for the duration that you are processing it
open file in exclusive mode in C#
Command-line tool for finding out who is locking a file
I have some code that saves a string to a file, something like this:
string TheFileJS = HttpRuntime.AppDomainAppPath + "\\SomePath\\" + ClientFileName + ".js";
if (File.Exists(TheFileJS) == true)
{
File.Delete(TheFileJS);
}
File.WriteAllText(TheFileJS, TheJS);
I'm using File.WriteAllText because I thought it would prevent problems with file locking but what's happening is that sometimes I get the error File is being used by another process. The problem is that it rarely happens, but once this exception occurs on a particular file, all client calls to this file then result in a 404.
What do I need to change in my code to make sure this error never happens?
I would imagine that you are running into problems with the lock still being open after the delete causing you to be unable to then rewrite the file.
The good news is that this is easily solvable by not deleting the file first.
From the docs for WriteAllText it says "Creates a new file, writes the specified string to the file, and then closes the file. If the target file already exists, it is overwritten."
What this means is that it effectively deletes the contents of the file anyway so checking if the file exists first is unnecessary. If you are not doing that check then you shouldn't run into any problems.
This is also where exception handling would come in handy. If this is critical code then you could retry or alert an admin immediately of the problem hopefully preventing all your clients then 404ing.
Try this. During file creation, if any stream is opened, it will be closed.
FileStream stream = File.Create(TheFileJS);
stream.Close();
I have Following Code in a Page_Load called function. When the Page is loaded the first time after starting Visual Studio, everything works out fine.
But any other opening call to the File after that returns IOException: "File is in use by another process", even when directly opening the File in VisualStudio Solution this Error is returned(of course not as Exception)
FileStream mailinglist_FileStream = new FileStream(#"\foobarFile.txt", FileMode.Open);
PeekingStreamReader mailinglist_Reader = new PeekingStreamReader(mailinglist_FileStream);
//Do some stuff with the file
mailinglist_FileStream.Close();
mailinglist_Reader.Close();
mailinglist_Reader.Dispose();
mailinglist_FileStream.Dispose();
Why is the file still locked? and why does fully restarting Visual Studio reset the File?
when checking file-Properties it says:
Build Action: Content
Copy to output directory: do not Copy
I am only reading this File. can i do something similiar to adLockOptimistic, so that multiple processes can access the File?
Why is the file still locked? and why does fully restarting Visual
Studio reset the File? when checking file-Properties it says [...]
I don't know why the file is still locked: probably because your code fails before the stream is closed/disposed.
About "why fully restarting Visual Studio [...]": because you may be using IIS Express or ASP.NET Dev Server whose are closed when you close the IDE, so locks on files are released since the process holding the locks is no longer running.
And about "why is the file still locked?[...]" it could be because the file stream isn't closed because sometimes the thread may not end successfully and the locks aren't released.
As other answer said, check how using block may avoid that IDisposable objects wouldn't be disposed:
// FileShare.ReadWrite will allow other processes
// to read and write the target file even if other processes
// are working with the same file
using var mailinglist_FileStream = new FileStream(#"\foobarFile.txt", FileMode.Open, FileShare.ReadWrite);
using var mailinglist_Reader = new PeekingStreamReader(mailinglist_FileStream);
// Do your stuff. Using blocks will call Dispose() for
// you even if something goes wrong, as it's equal to a try/finally!
I am only reading this File. can i do something similiar to
adLockOptimistic, so that multiple processes can access the File?
Yes, take a look at File.Open method and FileShare enumeration:
File.Open: http://msdn.microsoft.com/en-us/library/y973b725.aspx
FileShare enum: http://msdn.microsoft.com/en-us/library/system.io.fileshare.aspx
Learn to use using:
using (FileStream fileStream = File.Open(#"C:\somefile", FileMode.Open, FileAccess.Read))
{
...
}
The using construct ensures that the file will be closed when you leave the block even if an exception is thrown.
Your problem might not be here, but somewhere else in your code. You'll have to go through all your code and look for places where you have opened files but not put it inside a using statement.
An old question but unfortunately the given answers can be not applicable to the question.
The problem specifically in Windows lies in two aspects of Windows behavior:
a) when the handle to the file, opened for writing, is closed, the Microsoft Antimalware Service opens the file to check the newly written data for malware;
b) the OS itself keeps the file opened for some time after all handles to it are closed. This time can be from seconds to many minutes depending on the nature of the file and other factors.
We saw this problem many times in our products and had to provide special support for this case - our kernel-mode attempts to close the file as soon as the last handle to it is closed.
Try using using blocks, it may not fix your lock problem, but it is better form for disposable objects.
using (FileStream mailinglist_FileStream = new FileStream(#"\foobarFile.txt", FileMode.Open))
{
using (PeekingStreamReader mailinglist_Reader = new PeekingStreamReader(mailinglist_FileStream))
{
...
}
}
Also, try closing mailinglist_Reader before mailinglist_FileStream.
I am trying to renme a file/folder, when i try to rename a file, i got an error, file is already in use, it is just my guess that it is caused by w3wp.exe iis process? some time its says, access to the path is denied, although the file does exist, and there are no special permission, i have all the permission to copy/delete/move and everything for the file/folder.
How to fix this problem.
the folder contains jpeg files.
this happen: when i copy a file then try to rename it.
this happen: when i rename a file then try to delete it.
what i mean to say is that it happen when i already use a file operation then for second time it gives me this error :(
this is the error:
The process cannot access the file 'C:\images\audio-aif-old.png' because it is being used by another process.
file.move(source,destination);
i am using C#. iis 6, asp.net.
Directly , ans is no. But you can delete old copy and create a new copy. See this. http://www.aspnettutorials.com/tutorials/file/file-renfile-aspnet2-csharp.aspx
Some other program must relinquish the file. If you've written a program that's still running then that must be shut down. If the file is currently open for writing you must also ensure that it's been appropriately closed. Try creating another file and see if you have the same problem with that one.
The CopyTo method of FileInfo class throws an IOException
The process cannot access the file 'C:\Data\Test.XML' because it is being used by another process.
Any ideas on why this should happen? I understand that copying a file just requires read access. So ideally even if the file is write protected or is opened by some other program the CopyTo should have no problem executing.
FileInfo copyFile = null;
//currentFile.FileInformation is of type FileInfo which is referring to the file for which a copy is being created. In this case it is C:\Data\Test.XML
System.IO.FileInfo file = new FileInfo(currentFile.FileInformation.FullName);
// Constructing name for the temporary copy of Test.XML
string newName = "Temp Copy of " + currentFile.FileInformation.Name;
//This is where I get the exception. The CopyTo fails...
copyFile = file.CopyTo(System.IO.Path.Combine(currentFile.FileInformation.DirectoryName, newName), true);
fs = System.IO.File.Open(copyFile.FullName, FileMode.Open);
Also some important points to note :
I have write access to the folder to which I am trying to copy. This is happening with only certain files.
The file for which I am trying to create a copy of is not Read-only.
Please let me know if I can provide you with any more details
Thanks in advance
Download sysinternal's process explorer
put a breakpoint on File.CopyTo
in process explorer, search for the file name, it will tell you which process got it open
Another process might have specified the FILE_SHARE_READ mode when it opened the file, which would prevent you from even reading it.
You can use Process Explorer to find that process.
If you're using Windows, try using Process Explorer to determine what process is using the files you are trying to copy.