What does it mean 'to work in a terminal' - The terminal, the TTY, and the shell

Posted by urosp@reddit | linux | View on Reddit | 12 comments

I just wrote a breakdown on what it really means to 'work in the terminal' on Linux. This text breaks down what is a terminal emulator, pty and a shell.

This text is aimed at folks who have played around with the terminal a bit (pretty much everyone on Linux!) and are curious to understand what's going on under the hood. Just scratching the surface here, it should be a quick 10 minute read with some C program examples.

If this is new to you, you might find it interesting to look into how the emulation of ancient hardware from the 70s plays a role here!

I hope it's useful!

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edparadox@reddit

I am confused. It's not about "working in the terminal", but what a terminal, a shell, etc. is.

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omicronns@reddit

What is the actual difference between tty and pty? I see that ttys are used when switching to text mode virtual console, but how they differ is not explained.

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TheG0AT0fAllTime@reddit

tty is teletype. We used to have literal terminals with keyboards which serial off to a main server and people interacted on the system by logging into their username over the terminal in their own little session.

pty is a psuedo teletype. It's what your shell and ssh and such do to emulate a tty experience.

There's probably a better way to word this.

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Diligent_End8130@reddit

Thx, l like your write-up on this topic! Very interesting also for people knowing just how to launch the "terminal" and want to know beyond (diving into the *nix philosophy)

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urosp@reddit (OP)

Glad you liked it! That was exactly the intent. The first step after just launching the "terminal" (whatever that is!) and understanding the system a little deeper. And as you mentioned, this goes back all the way to Unix, from decades ago.

More to come soon!

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urosp@reddit (OP)

My pleasure! Please consider checking the rest of the website!

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RetiredApostle@reddit

I work in the console.

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urosp@reddit (OP)

That's the best way to do it!