A cross-platform pseudoterminal (PTY) library for .NET that enables spawning and interacting with terminal processes on Windows, Linux, and macOS.

• Cross-Platform Support: Works on Windows (using ConPTY), Linux, and macOS
• Simple API: Easy-to-use async API for spawning terminal processes
• Full PTY Control: Read/write streams, resize terminal, handle process exit events
• Unicode Support: Full UTF-8 support including complex characters
• .NET Standard 2.0: Compatible with .NET Core 2.0+, .NET 5+, and .NET Framework 4.6.1+

Install via NuGet Package Manager:

dotnet add package Porta.Pty

Or via the Package Manager Console in Visual Studio:

Install-Package Porta.Pty

using Porta.Pty;
using System.Text;

// Configure the terminal options
var options = new PtyOptions
{
    Name = "MyTerminal",
    Cols = 120,
    Rows = 30,
    Cwd = Environment.CurrentDirectory,
    App = RuntimeInformation.IsOSPlatform(OSPlatform.Windows) 
        ? Path.Combine(Environment.SystemDirectory, "cmd.exe") 
        : "/bin/bash",
    Environment = new Dictionary<string, string>
    {
        { "MY_VAR", "value" }
    }
};

// Spawn the terminal process
using IPtyConnection terminal = await PtyProvider.SpawnAsync(options, CancellationToken.None);

// Handle process exit
terminal.ProcessExited += (sender, e) => 
{
    Console.WriteLine($"Terminal exited with code: {e.ExitCode}");
};

// Write to the terminal
byte[] command = Encoding.UTF8.GetBytes("echo Hello World\r");
await terminal.WriterStream.WriteAsync(command, 0, command.Length);
await terminal.WriterStream.FlushAsync();

// Read from the terminal
byte[] buffer = new byte[4096];
int bytesRead = await terminal.ReaderStream.ReadAsync(buffer, 0, buffer.Length);
string output = Encoding.UTF8.GetString(buffer, 0, bytesRead);
Console.WriteLine(output);

// Resize the terminal
terminal.Resize(80, 24);

flowchart TB
    subgraph Entry["Entry Point"]
        PtyProvider["PtyProvider<br/>(Static class)"]
    end

    subgraph Platform["PlatformServices"]
        direction LR
        WinProvider["Windows<br/>Provider"]
        LinuxProvider["Linux<br/>Provider"]
        MacProvider["macOS<br/>Provider"]
    end

    subgraph Connections["Platform Connections"]
        direction LR
        PseudoConsole["PseudoConsole<br/>Connection<br/>(ConPTY API)"]
        LinuxPty["Unix PTY<br/>Connection<br/>(forkpty)"]
        MacPty["Unix PTY<br/>Connection<br/>(forkpty)"]
    end

    PtyProvider -->|"SpawnAsync(PtyOptions)"| Platform
    WinProvider --> PseudoConsole
    LinuxProvider --> LinuxPty
    MacProvider --> MacPty

    PseudoConsole -->|"implements"| IPtyConnection["IPtyConnection"]
    LinuxPty -->|"implements"| IPtyConnection
    MacPty -->|"implements"| IPtyConnection

• Uses the Windows ConPTY (Pseudo Console) API introduced in Windows 10 1809
• Leverages CreatePseudoConsole, ResizePseudoConsole, and ClosePseudoConsole native functions
• Process isolation via Windows Job Objects for clean process termination
• Implements proper cleanup order per Microsoft documentation

• Uses POSIX PTY functions (forkpty, openpty)
• Sets appropriate terminal environment variables (TERM=xterm-256color)
• Clears conflicting environment variables (TMUX, screen sessions)

• Vanara.PInvoke.Kernel32: Windows API P/Invoke bindings
• Mono.Posix.NETStandard: POSIX API bindings for Unix platforms

This project is licensed under the MIT License - see the LICENSE file for details.

Contributions are welcome! Please feel free to submit a Pull Request.