Interactive terminal (PTY)

The PTY (pseudo-terminal) module allows you to create interactive terminal sessions in the sandbox with real-time, bidirectional communication.

Unlike commands.run() which executes a command and returns output after completion, PTY provides:

Real-time streaming - Output is streamed as it happens via callbacks
Bidirectional input - Send input while the terminal is running
Interactive shell - Full terminal support with ANSI colors and escape sequences
Session persistence - Disconnect and reconnect to running sessions

Create a PTY session

Use sandbox.pty.create() to start an interactive bash shell. This example runs echo 'hello world', then exits and prints the terminal output.

import { Sandbox } from 'e2b'

const sandbox = await Sandbox.create()

const terminal = await sandbox.pty.create({
  cols: 80,                    // Terminal size in characters
  rows: 24,
  envs: { MY_VAR: 'hello' },   // Optional environment variables
  cwd: '/home/user',           // Optional working directory
  user: 'root',                // Optional user to run as
  onData: (data) => {
    // Called whenever the terminal outputs data
    process.stdout.write(data)
  },
})

// terminal.pid contains the process ID
console.log('Terminal PID:', terminal.pid)

// Send input to the PTY. Data must be bytes (Uint8Array), and the trailing newline "presses Enter".
await sandbox.pty.sendInput(terminal.pid, new TextEncoder().encode("echo 'hello world'\n"))

// The PTY runs an interactive login shell that won't exit on its own, so tell it
// to exit — otherwise wait() below blocks forever.
await sandbox.pty.sendInput(terminal.pid, new TextEncoder().encode('exit\n'))

// Wait for the terminal to exit (output is streamed to onData above)
await terminal.wait()

The PTY runs an interactive bash shell with TERM=xterm-256color, which supports ANSI colors and escape sequences.

PTY sessions have a configurable timeout that controls the session duration. The default is 60 seconds. For interactive or long-running sessions, set timeoutMs: 0 (JavaScript) or timeout=0 (Python) to keep the session open indefinitely.

import { Sandbox } from 'e2b'

const sandbox = await Sandbox.create()

const terminal = await sandbox.pty.create({
  cols: 80,
  rows: 24,
  onData: (data) => process.stdout.write(data),
  timeoutMs: 0,  // Keep the session open indefinitely
})

Send input to PTY

Use sendInput() in JavaScript or send_stdin() in Python to send data to the terminal. These methods return a Promise (JavaScript) or complete synchronously (Python) - the actual output is delivered to your onData callback (JavaScript) or to the on_pty callback you pass to wait() (Python).

import { Sandbox } from 'e2b'

const sandbox = await Sandbox.create()

const terminal = await sandbox.pty.create({
  cols: 80,
  rows: 24,
  onData: (data) => process.stdout.write(data),
})

// Send a command (don't forget the newline!)
await sandbox.pty.sendInput(
  terminal.pid,
  new TextEncoder().encode('echo "Hello from PTY"\n')
)

Resize the terminal

When the user’s terminal window changes size, notify the PTY with resize(). The cols and rows parameters are measured in characters, not pixels.

import { Sandbox } from 'e2b'

const sandbox = await Sandbox.create()

const terminal = await sandbox.pty.create({
  cols: 80,
  rows: 24,
  onData: (data) => process.stdout.write(data),
})

// Resize to new dimensions (in characters)
await sandbox.pty.resize(terminal.pid, {
  cols: 120,
  rows: 40,
})

Disconnect and reconnect

You can disconnect from a PTY session while keeping it running, then reconnect later with a new data handler. This is useful for:

Resuming terminal sessions after network interruptions
Sharing terminal access between multiple clients
Implementing terminal session persistence

import { Sandbox } from 'e2b'

const sandbox = await Sandbox.create()

// Create a PTY session
const terminal = await sandbox.pty.create({
  cols: 80,
  rows: 24,
  onData: (data) => console.log('Handler 1:', new TextDecoder().decode(data)),
})

const pid = terminal.pid

// Send a command
await sandbox.pty.sendInput(pid, new TextEncoder().encode('echo hello\n'))

// Disconnect - PTY keeps running in the background
await terminal.disconnect()

// Later: reconnect with a new data handler
const reconnected = await sandbox.pty.connect(pid, {
  onData: (data) => console.log('Handler 2:', new TextDecoder().decode(data)),
})

// Continue using the session
await sandbox.pty.sendInput(pid, new TextEncoder().encode('echo world\n'))

// Wait for the terminal to exit
await reconnected.wait()

Kill the PTY

Terminate the PTY session with kill().

import { Sandbox } from 'e2b'

const sandbox = await Sandbox.create()

const terminal = await sandbox.pty.create({
  cols: 80,
  rows: 24,
  onData: (data) => process.stdout.write(data),
})

// Kill the PTY
const killed = await sandbox.pty.kill(terminal.pid)
console.log('Killed:', killed)  // true if successful

// Or use the handle method
// await terminal.kill()

Wait for PTY to exit

Use wait() to wait for the terminal session to end (e.g., when the user types exit).

import { Sandbox } from 'e2b'

const sandbox = await Sandbox.create()

const terminal = await sandbox.pty.create({
  cols: 80,
  rows: 24,
  onData: (data) => process.stdout.write(data),
})

// Send exit command
await sandbox.pty.sendInput(terminal.pid, new TextEncoder().encode('exit\n'))

// Wait for the terminal to exit
const result = await terminal.wait()
console.log('Exit code:', result.exitCode)

Interactive terminal (SSH-like)

Building a fully interactive terminal (like SSH) requires handling raw mode, stdin forwarding, and terminal resize events. For a production implementation, see the E2B CLI source code which uses the same sandbox.pty API documented above.