NAME
tty - controlling terminal
DESCRIPTION
The file /dev/tty is a character file with major number 5
and minor number 0, usually of mode 0666 and owner.group
root.tty. It is a synonym for the controlling terminal of a
process, if any.
In addition to the ioctl() requests supported by the device
that tty refers to, the following ioctl() request is sup-
ported:
TIOCNOTTY
Detach the current process from its controlling termi-
nal, and remove it from its current process group,
without attaching it to a new process group (that is,
set its process group ID to zero). This ioctl() call
only works on file descriptors connected to /dev/tty;
this is used by daemon processes when they are invoked
by a user at a terminal. The process attempts to open
/dev/tty; if the open succeeds, it detaches itself from
the terminal by using TIOCNOTTY, while if the open
fails, it is obviously not attached to a terminal and
does not need to detach itself.
FILES
/dev/tty
SEE ALSO
mknod(1), chown(1), getty(1), console(4), ttys(4)