Unable to cancel NamedPipeClientStream reads on MacOS #101539
Description
Description
I am unable to cancel reads on NamedPipeClientStream on MacOS, as it seems to deadlock when closing the reader.
Reproduction Steps
The following code reproduces the problem on MacOS, but works fine on both Windows and Linux:
using System.IO.Pipes;
new Thread(() => {
using var host = new NamedPipeServerStream(
"cstest_pipes",
PipeDirection.InOut,
NamedPipeServerStream.MaxAllowedServerInstances,
PipeTransmissionMode.Byte,
PipeOptions.Asynchronous
);
Console.WriteLine("Host: Waiting for connection..");
host.WaitForConnection();
Console.WriteLine("Host: Connected :)");
while (true) {
Thread.Sleep(1000);
}
}).Start();
using var client = new NamedPipeClientStream(".", "cstest_pipes", PipeDirection.InOut, PipeOptions.Asynchronous);
Console.WriteLine("Client: Connecting..");
client.Connect(TimeSpan.FromSeconds(1));
Console.WriteLine($"Client: Connected: {client.IsConnected}");
var cts = new CancellationTokenSource();
var ct = cts.Token;
using var reader = new BinaryReader(client);
using var readerReg = ct.Register(reader.Close);
new Task(async () => {
Console.WriteLine("Client: Cancelling in 500ms..");
await Task.Delay(TimeSpan.FromMilliseconds(500));
Console.WriteLine("Client: Cancelling..");
cts.Cancel();
Console.WriteLine("Client: Cancelled :)");
}).Start();
while (!ct.IsCancellationRequested) {
Console.WriteLine("Client: Reading byte..");
try {
var b = reader.ReadByte();
Console.WriteLine($"Client: Byte received: 0x{b:02x}");
} catch (Exception) {
Console.WriteLine("Client: Exception caught while reading byte");
break;
}
}
Console.WriteLine("Client: Disconnected :)");Expected behavior
On stream close, I expect any existing reads to be cancelled and throw an exception. In other words, I expect the output of the above program to be something like this:
Client: Connecting..
Host: Waiting for connection..
Client: Connected: True
Client: Reading byte..
Host: Connected :)
Client: Cancelling in 500ms..
Client: Cancelling..
Client: Exception caught while reading byte
Client: Cancelled :)
Client: Disconnected :)
Actual behavior
In this case, a deadlock occurs between the stream closing and the stream being read from. In the example code above, the output of the program locks up here:
Host: Waiting for connection..
Client: Connected: True
Client: Reading byte..
Host: Connected :)
Client: Cancelling in 500ms..
Client: Cancelling..
Regression?
No response
Known Workarounds
No response
Configuration
Tested with SDK 9.0.100-preview.3.24204.13 (it happens on 8.0.203 as well)
MacOS Sonoma 14.4.1, arm64
Other information
No response