Unclear note about term emulator vs virtual console, and journalctl and dmesg

[Aster89]

The following note about term emulator vs. console seems to suggest that in a virtual console we always see the output of printk (or pr_info, or others) in the terminal. It doesn't seem to be the case. I always have to check sudo dmesg to find whatever I print from within the module.

Furthermore the note mention journalctl, but that shows the action of insmod and rmmod that I perform, not the output of the printing functions; again, that is shown in dmesg, which is unfortunately used but not presented first, just like journalctl.

I'm still at the beginning (I've read up to chapter 5.6 "Device Drivers"), but I think this is exactly what gives value to my comment.

Should I have better understanding in the future, I'll try to improve this wording myself, if somebody will not have done it yet.

lkmpg/lkmpg.tex

Lines 167 to 180 in 7b38f37

	\item Using X Window System.
	\label{sec:using_x}
	It is highly recommended that you extract, compile and load all the examples this guide discusses from a console.
	You should not be working on this stuff in X Window System.
	Modules can not print to the screen like \cpp|printf()| can, but they can log information and warnings, which ends up being printed on your screen, but only on a console.
	If you \sh|insmod| a module from an xterm, the information and warnings will be logged, but only to your systemd journal.
	You will not see it unless you look through your \sh|journalctl| .
	See \ref{sec:helloworld} for details.
	To have immediate access to this information, do all your work from the console.
	\end{enumerate}
	\section{Headers}
	\label{sec:headers}

[jserv]

Exactly, they are confusing. A pseudo{terminal,tty}, or PTY is a pair of pseudo-device endpoints which establish asynchronous, bidirectional communication IPC channel (with two ports) between two or more processes. An example using PTY is xterm-pty, which adds a PTY layer to xterm.js. For X11, xterm and rxvt are generally terminal emulators using tty, and current LKMPG does not distinguish from tty and pty though.