Create just a window frame

See more:

Linux

Bash

Xlib

Hello,

I am new to Xlib, so don't know pretty much all of it. :D I would like to create a window frame across the screen, just that, just a window frame (something like the border of the marquee when you select with the mouse). I like that window frame to show up on the screen, let's say in size of 300x300. That's it. :) I've only managed to create windows, but not this.

Please, could anyone help out.
Thank you for reading!

What I have tried:

Nothing... I have never programmed in Xlib with the exception of several windows and buttons. I am more of a Python/bash, kind of a person.