A real TTY device that's attached to a shell or terminal emulator will have interesting behaviour there, but you should get something back. To access a terminal you need to have permission to use it. Those are just the standard file permissions you see with ls -l and set with chmod : you need read permission to open the file and read it, and ...

Mar 21, 2019 · In Linux systems, there can be multiple tty device "consoles", to support potentially dozens of serial ports or more. tty0 is the current one in use, but Linux allows you to switch to another session by changing to a different tty, e.g., tty1. Linux (e.g., Ubuntu) supports up to 6 ttys by default, but this number is configurable.

A TTY (i.e. TeleTYpewriter) is a special device that lets people who are deaf, hard of hearing, or speech-impaired use the telephone to communicate, by allowing them to type text messages. A TTY is required at both ends of the conversation in order to communicate.

For each usb device there is a /sys/bus/usb/devices directory. The name of this directory depends on what port the usb device is plugged into. If the usb device is always plugged into the same usb port, the name of the directory will not change. The /sys/bus/usb/devices directory has a directory ttyUSB* with the same number as the /dev/ttyUSB*

It might be redirected to a serial device or a virtual console and by default points to /dev/tty0. When multiple console= options are passed to the kernel, the console output will go to more than one device; /dev/tty[0-N] (N is the highest attributed TTY number, e.g. 63) is one of the virtual consoles you switch to with control-alt-F1 and so on;

As Danny has stated tty is teletype terminals. The fact is that most of us have used it many times, but few of us have gone so far as to understand it. Here is a very good article which gives us a basic understanding of TTYs in Linux. The TTY Demystified

Jan 5, 2022 · They correspond to each individual terminal device on the system, either real or virtual. /dev/tty itself is special and points to the terminal of the process accessing it. The /dev/tty<number> ones are the Linux text-mode virtual consoles, which you

Feb 15, 2016 · The device connected to port 4.1 is a USB-serial adapter with four serial ports on a single device, therefore it has final values of 1.0, 1.1, 1.2, and 1.3 to signify all of the ttys on the single device.

@Diego Sevilla The original unix inventor did away with tty/ptys in Plan 9 , and there a terminal pretty much does just use a stream of in/out data. But in *nix, the ttys are still around and used by consoles and terminal emulators to e.g. control terminal size, flow control, line buffering, special key events, and other stuff. –

Apr 27, 2017 · /dev/tty is the controlling tty of the current process, for any process that actually opens this special file. It isn’t necessarily a virtual console device (/dev/ttyn), and can be a pty, a serial port, etc. If the controlling tty isn’t a virtual console, then the process has not to interact with console devices even if its pseudotty is ...