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Comment by tyingq | Hacker News Reader

Typing "echo <ctrl-v><esc>c<return>" to fix a garbled Vt100 like terminal remains embedded in my brain from long ago. Despite simpler things like "stty sane" existing. I don't know if maybe I was an admin on some box with a wonky stty, or why that's in my brain.

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I just type `reset` (maybe it's a zsh thing)

I don't remember, though I worked on a lot of oddball stuff. 3B2, Pyramid OSX, DGUX, etc.

Is <ctrl-v><esc> same as \x1b? Why are they same?

Yes, 0x1b is an ascii <esc>.

<ctrl-v> essentially means "insert the next key I press verbatim". So, like in Vim, <esc> would switch modes, unless you press <ctrl-v> first. Helpful if you're trying to insert a control character into a file, or echo a literal <ctrl-c> etc.

Does the terminal emulator handle the ctrl-v or shell or somewhere in kernel?

Whichever facility receives and processes the inbound keystrokes. In simple software that uses the terminal in canonical mode, the line discipline (usually in the kernel) handles the batching up of bytes into lines before passing them onto the software, and thus provides the line editing. In more complex software that puts the terminal into raw mode, it's then handled in that software; e.g., by libedit or readline or some bespoke terminal handling.

Why not just `clear` or `reset` terminal?

Wish I could remember why not :). I know now, but the muscle memory sticks.

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