Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. It only takes a minute to sign up.
Sign up to join this community
This tutorial says the following:
Every session is tied to a terminal from which processes in the session get their input and to which they send their output.
I think that this statement is incorrect, because say that I opened some program from the terminal (this program/process will be in the session connected to the terminal) and I redirected this program's stdout to a file. Now the program is not sending its output to the terminal.
Am I correct?
The statement correctly describes the nominal case: open a terminal, run a shell in its own session in this terminal, and run further programs from the shell. You are correct that the statement is not true in general: any process can send output and receive input from anywhere, not just the session's controlling terminal. Shell redirections are the most common way to make a process's standard input or output be something other than the terminal.
Don't expect a tutorial to cover all the cases. If it did, it would be incomprehensible.