Context Managers¶

libtmux provides context managers for all main tmux objects to ensure proper cleanup of resources. This is done through Python’s with statement, which automatically handles cleanup when you’re done with the tmux objects.

Open two terminals:

Terminal one: start tmux in a separate terminal:

$ tmux

Terminal two, python or ptpython if you have it:

$ python

Import libtmux:

import libtmux

Server Context Manager¶

Create a temporary server that will be killed when you’re done:

>>> with Server() as server:
...     session = server.new_session()
...     print(server.is_alive())
True
>>> print(server.is_alive())  # Server is killed after exiting context
False

Session Context Manager¶

Create a temporary session that will be killed when you’re done:

>>> server = Server()
>>> with server.new_session() as session:
...     print(session in server.sessions)
...     window = session.new_window()
True
>>> print(session in server.sessions)  # Session is killed after exiting context
False

Window Context Manager¶

Create a temporary window that will be killed when you’re done:

>>> server = Server()
>>> session = server.new_session()
>>> with session.new_window() as window:
...     print(window in session.windows)
...     pane = window.split()
True
>>> print(window in session.windows)  # Window is killed after exiting context
False

Pane Context Manager¶

Create a temporary pane that will be killed when you’re done:

>>> server = Server()
>>> session = server.new_session()
>>> window = session.new_window()
>>> with window.split() as pane:
...     print(pane in window.panes)
...     pane.send_keys('echo "Hello"')
True
>>> print(pane in window.panes)  # Pane is killed after exiting context
False

Nested Context Managers¶

Context managers can be nested to create a clean hierarchy of tmux objects that are automatically cleaned up:

>>> with Server() as server:
...     with server.new_session() as session:
...         with session.new_window() as window:
...             with window.split() as pane:
...                 pane.send_keys('echo "Hello"')
...                 # Do work with the pane
...                 # Everything is cleaned up automatically when exiting contexts

This ensures that:

The pane is killed when exiting its context
The window is killed when exiting its context
The session is killed when exiting its context
The server is killed when exiting its context

The cleanup happens in reverse order (pane → window → session → server), ensuring proper resource management.

Benefits¶

Using context managers provides several advantages:

Automatic Cleanup: Resources are automatically cleaned up when you’re done with them
Clean Code: No need to manually call kill() methods
Exception Safety: Resources are cleaned up even if an exception occurs
Hierarchical Cleanup: Nested contexts ensure proper cleanup order
Resource Management: Prevents resource leaks by ensuring tmux objects are properly destroyed

When to Use¶

Context managers are particularly useful when:

Creating temporary tmux objects for testing
Running short-lived tmux sessions
Managing multiple tmux servers
Ensuring cleanup in scripts that may raise exceptions
Creating isolated environments that need to be cleaned up afterward