Manage Multiple Interactive Sessions with Tmux

Manage Multiple Interactive Sessions with Tmux

All professions and crafts have tools. Mastering the tools is a big part of being successful and software development is no different. If anything, there are more tools to choose from in each and every area. In this article I’ll introduce tmux???one of the best tools for managing multiple interactive sessions. This is an essential activity for developers and sys admins who work with distributed systems and need to access multiple remote machines on a regular basis.

What Is Tmux?

Tmux stands for Terminal Multiplexer. A terminal is the console window in which you type commands in most operating systems. Tmux is designed for Unix-like operating systems and runs on pretty much everything you’re likely to use: Limux, OSX, Solaris, FreeBSD and NetBSD. You can find tmux here. Tmux lets you split your terminal window into multiple terminals and manage them. In addition, tmux lets you manage different sessions and re-attach them to existing sessions. That turns out to be the killer feature because it is very common to use tmux to manage interactive sessions with remote systems and those sessions tend to disconnect. With tmux you attach to your previous session and all your state is saved (unless the remote machine went down).

Basic Setup

Ok, let’s create a session. Open your terminal and type 'tmux new -s devx'. You should see something like:

Not too exciting so far. It looks like a regular terminal window except for the green bar at the bottom.

We can start an application now inside our tmux session as usual. For example, I can start vim, by typing ‘vim’:

When you’re inside a tmux session you operate in two contexts???tmux itself and the terminal or application that runs in the active pane inside tmux. When you type commands who should respond to these commands? Well, it depends. Sometimes you want to talk to the application and sometimes you want to talk to tmux. To disambiguate, tmux uses a key combination called prefix. That prefix is by default -b. Many people change that to -a?which is the prefix for a similar, but less powerful program, called ‘screen’. Many ex-screen users migrated to tmux but kept the ctrl-?prefix. To keep it generic and save some space I’ll just use

?for prefix from now own. Remember that if you didn’t change anything in your tmux configuration

?stands for -b.

For example, to detach from a session type

d, which really means press ?and b?at the same time, release both and the press ‘d‘.

You should see that vim disappeared along with the cool green bar and you’re back at the terminal where it says [detached].

Have no fear, nothing is lost. We can get back to our vim session. First, let’s check out our tmux sessions by typing ‘tmux list-sessions’:

You can see our ‘devx’ session right there. Let’s get back to our session. Type:

tmux attach-session -t devx 

And, we’re back. Enjoy your vim session.

Pane and Window Management

Let’s get to the bread and butter of tmux???multiple panes. With tmux you’re always inside of a pane. When you start a new session there is just a single session. To create additional sessions you can split the current pane into two panes. You can split vertically or you can split horizontally.

 To split horizontally type: 

%To split vertically type:

"

Here is what the screen looks like after I type both commands one after the other:

Note, that the cursor is now in the bottom right pane and the green bar says: “0:bash*” to reflect the fact that the application running in the active pane is bash.

Closing a pane is as simple as typing -d. Note that if you close the last pane, you effectively close your tmux session. You will not be able to attach again because there is nothing to which something could be attached. So, pay attention to the difference between detaching from a session vs. closing a session (closing the last pane).

To move between panes use

. That is simply click on the arrow key corresponding to the direction you want to move to. Some people have really intricate layout with lots of small panes and navigating between them with the arrow keys can be a little tedious. You can go directly to a particular pane too. To do that type

q. Tmux will display briefly a big number on each pane. While the numbers are visible, type the number and there you are.

Here is a crazy pane configuration that can definitely benefit from direct navigation

You can also resize panes in different directions by typing the following command:

:resizep -

The direction is L, R, U or D (I’m sure you can guess what they stand for) and the amount is the number of characters to grow by. For example, to grow the active pane by 10 characters to the right type:

:resizep -R 10

Tmux supports windows too. Each window takes over the whole screen and can have it split into its own panes. To create a new window type:

c.

Navigating between windows can be done by

n?for next window and

p?for previous window. If you prefer selecting from a visual list type

w?that will display a list of all windows.

To close a window you can close all its panes or to close immediately type

&

Tmux will ask you if you’re sure:

Scrolling

One common issue when working with tmux is that panes are often small and to see their contents you need to scroll them. No problem. Tmux has got you covered with the

[?command. This is called copy mode and lets you scroll up and down the active pane with the arrow keys. Vim commands are supported as well (e.g. : or G to jump to the bottom). Note that in copy mode no prefix is needed to navigate around. To get out of copy mode press ‘q‘. One useful bit of information that tmux provides is a little display in the top right corner of the active pane with two numbers. The left number shows how many lines are available to scroll down to (hidden below). The right number shows how many total lines are in the buffer.

Copy and Paste

This is something that can surprise many tmux users. You can copy and paste between panes (even of different sessions), but by default you can’t copy-paste between tmux and other programs. There are several solutions for different operating systems but they are outside the scope of this article. Check out https://github.com/tmux-plugins/tmux-yank?for a plugin solution.

To copy from one pane to another, first get into copy mode, then press , which will start highlighting your selection. When you’re done, press , which will put your selection in the paste buffer. Navigate to another pane and paste your selection by typing

].

Conclusion

Tmux gives you a great way to organize multiple interactive sessions logically and visually. You can have multiple long running sessions on your machine or on remote machines with multiple window in each session and multiple panes in each window. You can navigate easily between all of the above and resize the pane layout in each window to your liking. This is of course only scratching the surface. There is a lot more to tmux that I haven’t covered here.

devx-admin

devx-admin

Share the Post:
USA Companies

Top Software Development Companies in USA

Navigating the tech landscape to find the right partner is crucial yet challenging. This article offers a comparative glimpse into the top software development companies

Software Development

Top Software Development Companies

Looking for the best in software development? Our list of Top Software Development Companies is your gateway to finding the right tech partner. Dive in

India Web Development

Top Web Development Companies in India

In the digital race, the right web development partner is your winning edge. Dive into our curated list of top web development companies in India,

USA Web Development

Top Web Development Companies in USA

Looking for the best web development companies in the USA? We’ve got you covered! Check out our top 10 picks to find the right partner

Clean Energy Adoption

Inside Michigan’s Clean Energy Revolution

Democratic state legislators in Michigan continue to discuss and debate clean energy legislation in the hopes of establishing a comprehensive clean energy strategy for the

Chips Act Revolution

European Chips Act: What is it?

In response to the intensifying worldwide technology competition, Europe has unveiled the long-awaited European Chips Act. This daring legislative proposal aims to fortify Europe’s semiconductor

USA Companies

Top Software Development Companies in USA

Navigating the tech landscape to find the right partner is crucial yet challenging. This article offers a comparative glimpse into the top software development companies in the USA. Through a

Software Development

Top Software Development Companies

Looking for the best in software development? Our list of Top Software Development Companies is your gateway to finding the right tech partner. Dive in and explore the leaders in

India Web Development

Top Web Development Companies in India

In the digital race, the right web development partner is your winning edge. Dive into our curated list of top web development companies in India, and kickstart your journey to

USA Web Development

Top Web Development Companies in USA

Looking for the best web development companies in the USA? We’ve got you covered! Check out our top 10 picks to find the right partner for your online project. Your

Clean Energy Adoption

Inside Michigan’s Clean Energy Revolution

Democratic state legislators in Michigan continue to discuss and debate clean energy legislation in the hopes of establishing a comprehensive clean energy strategy for the state. A Senate committee meeting

Chips Act Revolution

European Chips Act: What is it?

In response to the intensifying worldwide technology competition, Europe has unveiled the long-awaited European Chips Act. This daring legislative proposal aims to fortify Europe’s semiconductor supply chain and enhance its

Revolutionized Low-Code

You Should Use Low-Code Platforms for Apps

As the demand for rapid software development increases, low-code platforms have emerged as a popular choice among developers for their ability to build applications with minimal coding. These platforms not

Cybersecurity Strategy

Five Powerful Strategies to Bolster Your Cybersecurity

In today’s increasingly digital landscape, businesses of all sizes must prioritize cyber security measures to defend against potential dangers. Cyber security professionals suggest five simple technological strategies to help companies

Global Layoffs

Tech Layoffs Are Getting Worse Globally

Since the start of 2023, the global technology sector has experienced a significant rise in layoffs, with over 236,000 workers being let go by 1,019 tech firms, as per data

Huawei Electric Dazzle

Huawei Dazzles with Electric Vehicles and Wireless Earbuds

During a prominent unveiling event, Huawei, the Chinese telecommunications powerhouse, kept quiet about its enigmatic new 5G phone and alleged cutting-edge chip development. Instead, Huawei astounded the audience by presenting

Cybersecurity Banking Revolution

Digital Banking Needs Cybersecurity

The banking, financial, and insurance (BFSI) sectors are pioneers in digital transformation, using web applications and application programming interfaces (APIs) to provide seamless services to customers around the world. Rising

FinTech Leadership

Terry Clune’s Fintech Empire

Over the past 30 years, Terry Clune has built a remarkable business empire, with CluneTech at the helm. The CEO and Founder has successfully created eight fintech firms, attracting renowned

The Role Of AI Within A Web Design Agency?

In the digital age, the role of Artificial Intelligence (AI) in web design is rapidly evolving, transitioning from a futuristic concept to practical tools used in design, coding, content writing

Generative AI Revolution

Is Generative AI the Next Internet?

The increasing demand for Generative AI models has led to a surge in its adoption across diverse sectors, with healthcare, automotive, and financial services being among the top beneficiaries. These

Microsoft Laptop

The New Surface Laptop Studio 2 Is Nuts

The Surface Laptop Studio 2 is a dynamic and robust all-in-one laptop designed for creators and professionals alike. It features a 14.4″ touchscreen and a cutting-edge design that is over

5G Innovations

GPU-Accelerated 5G in Japan

NTT DOCOMO, a global telecommunications giant, is set to break new ground in the industry as it prepares to launch a GPU-accelerated 5G network in Japan. This innovative approach will

AI Ethics

AI Journalism: Balancing Integrity and Innovation

An op-ed, produced using Microsoft’s Bing Chat AI software, recently appeared in the St. Louis Post-Dispatch, discussing the potential concerns surrounding the employment of artificial intelligence (AI) in journalism. These

Savings Extravaganza

Big Deal Days Extravaganza

The highly awaited Big Deal Days event for October 2023 is nearly here, scheduled for the 10th and 11th. Similar to the previous year, this autumn sale has already created

Cisco Splunk Deal

Cisco Splunk Deal Sparks Tech Acquisition Frenzy

Cisco’s recent massive purchase of Splunk, an AI-powered cybersecurity firm, for $28 billion signals a potential boost in tech deals after a year of subdued mergers and acquisitions in the

Iran Drone Expansion

Iran’s Jet-Propelled Drone Reshapes Power Balance

Iran has recently unveiled a jet-propelled variant of its Shahed series drone, marking a significant advancement in the nation’s drone technology. The new drone is poised to reshape the regional

Solar Geoengineering

Did the Overshoot Commission Shoot Down Geoengineering?

The Overshoot Commission has recently released a comprehensive report that discusses the controversial topic of Solar Geoengineering, also known as Solar Radiation Modification (SRM). The Commission’s primary objective is to

Remote Learning

Revolutionizing Remote Learning for Success

School districts are preparing to reveal a substantial technological upgrade designed to significantly improve remote learning experiences for both educators and students amid the ongoing pandemic. This major investment, which

Revolutionary SABERS Transforming

SABERS Batteries Transforming Industries

Scientists John Connell and Yi Lin from NASA’s Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) project are working on experimental solid-state battery packs that could dramatically change the

Build a Website

How Much Does It Cost to Build a Website?

Are you wondering how much it costs to build a website? The approximated cost is based on several factors, including which add-ons and platforms you choose. For example, a self-hosted