Because terminal emulators are literally the old terminal emulators (ye oldy screens + keyboard combos that looked like a computer but were just IO) and everything modern they do is just a hack.
Terminals with screens? What’s all that newfangled shit?
Nah, whippersnapper, this tech goes all the way back to teletypes. You didn’t get a fancy-shmancy “screen;” instead, it printed out the results of your commands. On actual paper!
Seriously though, that’s why the device files for terminals in Linux are named tty[$NUM] – “tty” is shorthand for “TeleTYpe.”
I believe it’s also why really primitive programs can’t scroll up and do things like writing an entire screen worth of content in order to emulate interactivity (as opposed to seeking the cursor backwards and replacing only the parts the program wants to replace): they’re using a version of the control protocol so primitive that it didn’t have a function to go backwards because teletypes didn’t need it due to physical impossibility. (That’s my theory, anyway – I haven’t dug deep enough into the guts of TERMCAP etc. to be sure. I’m also not actually old enough to have experienced that stuff, despite my joke above.)
Why is that actually?
Because fuck you! That’s why!
Edit: serious answer, I’m pretty sure it’s outputting the key events to the terminal line.
Because terminal emulators are literally the old terminal emulators (ye oldy screens + keyboard combos that looked like a computer but were just IO) and everything modern they do is just a hack.
Terminals with screens? What’s all that newfangled shit?
Nah, whippersnapper, this tech goes all the way back to teletypes. You didn’t get a fancy-shmancy “screen;” instead, it printed out the results of your commands. On actual paper!
Seriously though, that’s why the device files for terminals in Linux are named
tty[$NUM]– “tty” is shorthand for “TeleTYpe.”I believe it’s also why really primitive programs can’t scroll up and do things like writing an entire screen worth of content in order to emulate interactivity (as opposed to seeking the cursor backwards and replacing only the parts the program wants to replace): they’re using a version of the control protocol so primitive that it didn’t have a function to go backwards because teletypes didn’t need it due to physical impossibility. (That’s my theory, anyway – I haven’t dug deep enough into the guts of TERMCAP etc. to be sure. I’m also not actually old enough to have experienced that stuff, despite my joke above.)