How to Properly Implement Asynchronous File I/O with Cancellation in C# without Memory Leaks?
I'm wondering if anyone has experience with I'm currently working on a .NET 6 console application that performs asynchronous file I/O operations... I've implemented a method to read large text files and then process their content, but I'm encountering issues with cancellation tokens not behaving as expected, leading to potential memory leaks. My implementation looks something like this: ```csharp public async Task ProcessFileAsync(string filePath, CancellationToken cancellationToken) { using (var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read, 4096, FileOptions.Asynchronous)) { using (var reader = new StreamReader(stream)) { string line; while ((line = await reader.ReadLineAsync().ConfigureAwait(false)) != null) { cancellationToken.ThrowIfCancellationRequested(); // Process the line here } } } } ``` I've attempted to call this method with a cancellation token from my main method like so: ```csharp var cts = new CancellationTokenSource(); try { await ProcessFileAsync("largefile.txt", cts.Token); } catch (OperationCanceledException) { Console.WriteLine("Operation was canceled."); } ``` However, I’ve noticed that even after cancellation is requested, the file reading seems to continue for a while, and I suspect that it might be retaining references to the file stream or the reader, causing memory not to be released immediately. I'm also unsure if I need to explicitly dispose of anything else beyond the `using` statements. Are there best practices I should follow to ensure that cancellation is handled properly and no memory leaks occur? Additionally, I sometimes get the following warning during cancellation: `The operation was canceled, but resources may still be in use.` Can anyone suggest what I'm overlooking here or how I can improve my implementation?