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Is it accurate to call the Ubuntu GUI a TTY by itself? I know that the term TTY isn't necessarily dealing with terminal consoles or terminal emulators (CLI environments) but also to what I can refer to as GUI, if the definition is broad enough.

So, my question can actually be comprised of the following 2:

  1. Is it accurate to name the Ubuntu GUI (or any other operating system GUI) a "TTY" for that matter?
  2. Is it true to say that any Window (like a directory window or a gedit/geany window) is a TTY by itself or just a (window) part of the larger GUI TTY?

4 Answers4

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Is it accurate to name the Ubuntu GUI (or any other operating system GUI) a "TTY" for that matter?

A desktop needs a tty to run but that does not make the GUI a tty. You should call it a session and a tty you use to login either to command line session or a desktop session.

Is it true to say that any Window (like a directory window or a gedit/geany window) is a TTY by itself or just a (window) part of the larger GUI TTY?

No. Those are processes (within a session).

Rinzwind
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  • Hi, thank you. I thumbed up. I gave the bounty to the new comer guy even though I wanted to give it to you but when I saw you have 157k I thought you will prefer I'll give to me him (or her). –  May 09 '17 at 15:27
  • He has only 80 rep points. –  May 09 '17 at 15:34
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TTY really is an instance of virtual terminal. Early computers were just giant boxes, to which a real, physical terminal was connected and are generally called TTY (short for teletype). Virtual terminals are called virtual for that exact reason - your computer is now one single unit, and you have couple different virtual software teletypes (more specifically, for Ubuntu it's 6 ttys, but you can spawn more. See my answer here: https://askubuntu.com/a/817859/295286). Within TTY you can run processes, be it a text-based shell like bash or graphical server within which runs a graphical shell.

What happens precisely is that you have specific instance of GUI running ( or in more technical terms, you have X11 server running ) in a particular tty. In case of Ubuntu, it defaults to TTY #7. When I was using Fedora 21, that defaults to TTY1. And you can have multiple instances of GUI, see this for example: Start another GUI on different TTY

So effectivelly, GUI session is nothing more than a separate process running within a TTY.

Additional info:

Sergiy Kolodyazhnyy
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A desktop runs on a TTY. A window is a different process, non-TTY related. It just shows in the desktop environment.

Kyngo
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After reading the answers here I understand this:

In computers of some previous era, a tty was a typing machine you would plug into a computer, a keyboard with a small output screen.

Modern operating systems come with multiple virtual tty.

Based on the modern tty, we have at least one GUI or at least one CLI.

Both of these GUI or CLI are sessions based on the tty, and can have sub sessions (sometimes are actually windows).

tty(s) are special files while GUI, and CLI, all are basically different processes.

  • I'm afraid you have misunderstood. Modern computers (well, operating systems, this isn't a hardware thing) still come with multiple virtual TTYs. Virtual machines have nothing whatseover to do with this. The tty is more of a special file (like device files) than a process. Oh, and LVM is a device mapper, virtual machines are VMs, irrespective of what OS they happen to be running. – terdon May 10 '17 at 09:31
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    Note that window is a separate processes as well, they are "children" of a parent GUI process. Otherwise, you're getting it. Good job ! – Sergiy Kolodyazhnyy May 10 '17 at 18:10
  • @terdon how is my answer after my edit and Sergiy's edit? Would appreciate your take on this so much! –  May 16 '17 at 09:37
  • @terdon I'd gladly ask deletion of comments after both edits; only one thing I miss, please --- what is "more than a special file than a process"; isn't special file and process essentially different? –  Sep 06 '19 at 02:03
  • Yes. I mean a tty is a special file, it is not a process. The idiom "more of an A than a B" is just a way of saying that. – terdon Sep 06 '19 at 11:28