dotnet / dotnet/Docker.DotNet

Container does not receive stdin input

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Description

When I start a container and attach to its input stream, the container does not receive the bytes written to the stream.

**Output of `dotnet --info`:**

```
.NET SDK:
Version: 8.0.100
Commit: 57efcf1350
Workload version: 8.0.100-manifests.8d38d0cc

Runtime Environment:
OS Name: Windows
OS Version: 10.0.19045
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\8.0.100\
```

**What version of Docker.DotNet?:**

```
3.125.15
```

**Steps to reproduce the issue:**
1. This is my test program _(Program.cs)_ for the container:
```
using var input = Console.OpenStandardInput();
byte[] buffer = new byte[100];
int bytesCount = input.Read(buffer, 0, buffer.Length);
Console.WriteLine($"Received {bytesCount} bytes.");
```
(The test program is attached to this issue.)

2. Here is the _Dockerfile_ I'm using to build the Linux image:
```
FROM mcr.microsoft.com/dotnet/sdk:6.0 AS build
COPY Read.csproj src/Read.csproj
COPY Program.cs src/Program.cs
RUN dotnet publish --output out src

FROM mcr.microsoft.com/dotnet/runtime:6.0 AS final
WORKDIR /app
COPY --from=build out .
ENTRYPOINT ["dotnet", "Read.dll"]
```

3. Build the image using the following command:
```
docker build -t read .
```

4. I run the following code to start a container and write to its stdin stream:
```
using Docker.DotNet;
using Docker.DotNet.Models;
using System.Text;

using var client = new DockerClientConfiguration().CreateClient();
var response = await client.Containers.CreateContainerAsync(new CreateContainerParameters
{
Image = "read:latest",
AttachStdin = true,
// When I set this flag the container never finishes running and the call to WaitContainerAsync() times out.
// OpenStdin = true,
StdinOnce = true
});

await client.Containers.StartContainerAsync(response.ID, new ContainerStartParameters());

using (var inputStream = await client.Containers.AttachContainerAsync(response.ID, tty: false, new()
{
Stream = true,
Stdin = true
}))
{
byte[] bytes = Encoding.UTF8.GetBytes($"Hello{Environment.NewLine}Bye{Environment.NewLine}");
await inputStream.WriteAsync(bytes, 0, bytes.Length, CancellationToken.None);
inputStream.CloseWrite();
}

var cancellationTokenSource = new CancellationTokenSource();
cancellationTokenSource.CancelAfter(TimeSpan.FromSeconds(10));
await client.Containers.WaitContainerAsync(response.ID, cancellationTokenSource.Token);

var logs = await client.Containers.GetContainerLogsAsync(response.ID, tty: false, new()
{
ShowStdout = true,
ShowStderr = true
});
var (stdOut, stdError) = await logs.ReadOutputToEndAsync(CancellationToken.None);
Console.WriteLine($"Output: [{string.Concat(stdOut, stdError)}]");
```

**What actually happened?:**
The container outputs `Received 0 bytes.` indicating that it's not receiving the input.

As mentioned in the code comment above, if I set `OpenStdin = true` on the `CreateContainerParameters` when creating the container, the container freezes. In particular, by adding some file logging, I can determine that it freezes at the `int bytesCount = input.Read(buffer, 0, buffer.Length);` line.

**What did you expect to happen?:**

The container must output `Received 12 bytes.`

**Additional information:**
[Read.zip](https://github.com/dotnet/Docker.DotNet/files/13658317/Read.zip)

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