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Why GNU Screen is the Superior Terminal Multiplexer

Sun, 19 May 2024

I received a request to write something about why I use GNU Screen instead of tmux (so yes, I do accept topic requests - please feel free to contact me if you have ideas).

Terminal multiplexers are indispensable tools for anyone who spends significant time in the command line. They allow you to create persistent sessions, detach and re-attach from them, and even split your terminal into multiple panes. GNU Screen remains the superior choice for several reasons.

GNU Screen, a component of the GNU Project, has a rich history and a long-standing reputation as a reliable terminal multiplexer. The GNU Project, initiated by Richard Stallman in 1983, is a cornerstone of the free software movement and has been instrumental in promoting user freedom. Developed with essential tools like the GNU Compiler Collection (GCC) and the GNU C Library (glibc), Screen ensures high compatibility.

The heart of the free software movement is user freedom. With GNU Screen, this freedom is not just a concept but a tangible reality. Licensed under the GNU General Public License version 3.0 or later (GPL-3.0-or-later), Screen empowers you, the user, by granting these essential freedoms. For instance, you have the freedom to run the program for any purpose, to study how it works and change it, share copies, provided that you pass on those same freedoms. This ensures that any derivative works must be released under the same terms, defending freedom by denying people the ability to take away those freedoms from others.

On the other hand, tmux is under the ISC license, a permissive free software license. While this license grants users the same freedoms, it's essential to be aware of its limitations. Unlike the GPL-3.0-or-later GNU Screen uses, the ISC license does not mandate preserving those freedoms when sharing copies. This could lead to a scenario where the software's freedoms gradually diminish as proprietary forks emerge. It's important to consider this potential risk when choosing a terminal multiplexer.

While licensing is a crucial factor, it's important to note that GNU Screen offers more than freedom. It also provides features that set it apart from tmux. One of the most significant advantages of Screen is its ability to connect over serial ports. This means you can use Screen to interact with embedded devices, manage servers and network devices with serial consoles, and access a system's console in recovery situations when the network is unavailable. This feature alone can be incredibly useful in various scenarios. tmux lacks this capability, limiting its use in environments where serial connections are needed. GNU Screen offers some additional features:

  • Multiuser Support: Allows multiple users to connect to the same session, facilitating collaboration and remote assistance.
  • Logging: Easily log your terminal sessions for later review or auditing.

While tmux can replicate some of these features with plugins or workarounds, Screen's native support makes it a more streamlined and efficient solution.

Beyond that, both multiplexers offer similar functionality, including:

  • Session Management: Create, detach, and re-attach to persistent sessions.
  • Window and Pane Management: Split your terminal into multiple windows and panes
  • Copy and Paste: Copy and paste between windows and panes.
  • Customization: Configure keybindings, colors, and other aspects to your liking.

If you're familiar with tmux, transitioning to Screen will be relatively straightforward. If you're considering switching to Screen, you can do so without significant disruption to your workflow or the need for extensive relearning, making the transition smooth and efficient.

In conclusion, while GNU Screen and tmux are capable terminal multiplexers, GNU's strong commitment to user freedom through their GPL-3.0-or-later license makes it the winner. By choosing Screen, you're getting a powerful tool and supporting a project that actively defends your right to use, study, change, and share software. This commitment to user freedom, unique features, and high compatibility make GNU Screen the superior choice for terminal multiplexing. Additionally, GNU Screen benefits from a vibrant community of users and developers, ensuring a wealth of resources and support for those using it.