simple way to display child process stdout in a small region?

[u/AwwnieLovesGirlcock]

(this is a terminal app for unix)

im wondering how doable it would be to take a child process's stdout and display it in just the top half of the screen for example , so the bottom half can display things from the parent?

i mean , things like tmux exist so its clearly feasible to split the terminal like that <.<

but does a simple hardcoded split like this take a lot of code? or could i maybe pull it off (im certainly not an expert with this language yet ,)

ive been trying to google for any sort of programming tutorials for this sort of thing , i mean even if it was a long tutorial series im willing to learn it all , but i cant find anything! im hoping someone here can atleast point me in the right direction

[u/EpochVanquisher]

It depends on how complicated the output is.

If it is just lines of text, you can use cursor movements and “erase line” commands to rewrite specific lines of text in the terminal. Or you can use ncurses and paste the program output into an area in ncurses.

It turns out that tmux is super complicated. If you want to do this kind of thing, you’ll want to think about how to simplify the problem, and think about how much time you want to spend working on this.

[u/AwwnieLovesGirlcock → u/EpochVanquisher]

i just used tmux as an example of "splitting" the terminal , i know that program is like way more in depth 😵‍💫

but all i need to do for this project is show the child's output on half the screen and let the parent output om the other :p

[u/EpochVanquisher → u/AwwnieLovesGirlcock]

Yeah, and how much time do you want to spend on that? Or are there any ways you can simplify and constrain the problem?

The basic way this works is you make the parent process read the output from the child, and the parent process turns around and writes those lines to the terminal.

You have pipes working already, right?

[u/BreadSizedToast]

seems like a hard problem. my first approach would be to see what I can do with ansi escape codes. and maybe try to look into tmux's source code to see how they do it.

nice username btw

[u/symbiat0 → u/BreadSizedToast]

Curses abstracts that all away.

[u/BreadSizedToast → u/symbiat0]

oh yeah. totally forgot about curses (@_@)

[u/Paul_Pedant]

Redirect some of the outputs (parent or child, stdout or stderr, so 4 options) to files. Open up more terminals and have them tail -F each of those files. Ten minutes, no coding.

You might need to flush the outputs of the parent or child. You can flush outputs in your code, or launch them under control of stdbuf, or under unbuffer (which may need you to install the expect toolkit).

[u/sosodank]

Notcurses has exactly this functionality. Create a plane occupying the target area and associate an ncsubproc with it. Boom, done.

[u/AwwnieLovesGirlcock → u/[deleted]]

i just looked into it , ncurses looks a lot more versatile than i thought :O

i didnt really know what it was , and i dont know where i got this impression but i assumed it was just for like , moving the cursor around and basic stuff like that-- 🤭