Support writing to stdin when executing a remote command

[hifi]

SSH.NET currently does not support executing a command (without shell) with an option to directly write to the stdin of the executed program. A writable stream is needed for that.

This is a critical feature when you need to pipe large amounts of data from SSH.NET to remote commands.

[hifi]

So it was rather easy to implement but here's the minimum amount of changes required to get writing working:

https://gist.github.com/hifi/d7c4e3689e28df13893fc0c4fd813706

Ideally it should use something like PipeStream to expose a InputStream for writing instead of raw byte arrays. Also it's worth noting that SendEof must be called to close stdin. Failing to do that, a program you are executing could end up waiting input forever. Closing this InputStream should do this implicitly so you can signal the program on the other send that you are finished.

[Livius90]

Is this feature available now? I would like to send diskimage datas from C# to a stdin pipe of dd over SSH, like in this example.

Is that pipe data sending Linux style is available to use in SSH.NET?

# dd bs=16M if=/dev/sda | ssh root@serverB "dd bs=16M of=/dev/sda"

[Rob-Hague]

This was added in version 2024.0.0 in #1293