A pseudo-tty is a device that is not associated with any real hardware,
and it is used to simulate the function of a real tty.
Users of networking products should already be
familiar with pseudo-ttys, as they
are the devices used to log in on remote machines.
A pseudo-tty is represented by two software devices that appear
in a listing of /dev as ptyp and
ttyp, each followed by a number.
The former is called the ``master'' tty and the latter the
Between the two, they simulate a functional tty.
Pseudo-ttys are created with the mkdev ptty command.
To configure the pseudo-ttys,
log in as root and enter the following command:
This automatically creates the necessary devices, updates the files /etc/inittab and /etc/conf/cf.d/init.base, and updates the NSPTTYS kernel parameter (the maximum number of pseudo-ttys) as necessary. If this value is increased, a kernel relink will be necessary.