xref: /openbsd-src/libexec/getty/ttys.5 (revision aa6c9a0121cbbd806c80f46b559a42d78e392869)

.\"	$OpenBSD: ttys.5,v 1.14 2022/07/29 13:56:36 millert Exp $
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.\"     from: @(#)ttys.5	8.1 (Berkeley) 6/4/93
.\"
.Dd $Mdocdate: July 29 2022 $
.Dt TTYS 5
.Os
.Sh NAME
.Nm ttys
.Nd terminal initialization information
.Sh DESCRIPTION
The
.Nm
file contains information that is used by various routines to initialize
and control the use of terminal special files.
This information is read with the
.Xr getttyent 3
library routines.
.Pp
There is one line in the
.Nm
file per special device file.
Fields are separated by tabs and/or spaces.
Fields comprised of more than one word should be enclosed in double quotes
.Pq Ql \&" .
Blank lines and comments may appear anywhere in the file; comments
are delimited by hash marks
.Pq Ql #
and newlines.
Any unspecified fields will default to null.
.Pp
Each line in
.Nm
is of the format:
.Dl tty command type flags
.Pp
The first field is the
name of the terminal special file as it is found in
.Pa /dev .
.Pp
The second field is the command to execute for the line,
usually
.Xr getty 8 ,
which initializes and opens the line, setting the speed, waiting for
a user name and executing the
.Xr login 1
utility.
It can be, however, any desired command, for example
the start up for a window system terminal emulator or some other
daemon process, and can contain multiple words if quoted.
.Pp
The third field is the type of terminal usually connected to that
tty line, normally the one found in the
.Xr terminfo 5
database file.
The environment variable
.Dv TERM
is initialized with the value by either
.Xr getty 8
or
.Xr login 1 .
.Pp
The remaining fields set flags in the
.Fa ty_status
entry (see
.Xr getttyent 3 )
or specify a window system process that
.Xr init 8
will maintain for the terminal line.
The following is a list of permitted flags for each tty:
.Bl -tag -width xxxxxxx
.It Ar on
Specify that
.Xr init 8
should execute the command given in the second field.
.It Ar off
The opposite of on.
.It Ar secure
If
.Ar on
is also specified, allows users with a user ID of 0 to log in on this line.
If set for the
.Ar console
entry, then
.Xr init 8
will start a single-user shell without asking for the superuser password.
.El
.Pp
Additionally, the following flags modify the default behavior of
the terminal line.
Some of these flags may not be supported by a terminal line driver.
The flag fields should not be quoted.
.Bl -tag -width xxxxxxx
.It Ar local
Treat the line as if it is locally connected.
.It Ar rtscts
Use RTS/CTS hardware flow control, if
possible.
.It Ar mdmbuf
Use DTR/DCD flow control if possible.
.It Ar softcar
Ignore hardware carrier on the line.
.El
.Pp
The string
.Ar window=
may be followed by a quoted command string which
.Xr init 8
will execute
.Em before
starting the command specified by the second field.
.Pp
Changes to the
.Nm
file take effect after it has been reloaded by
.Xr init 8 ,
which can be triggered by sending it a
.Dv HUP
signal.
Reloading the
.Nm
file does
.Em not
change the state of the device-specific terminal flags described above.
The
.Xr ttyflags 8
utility can be used to set those flags.
.Sh FILES
.Bl -tag -width /etc/ttys -compact
.It Pa /etc/ttys
.El
.Sh EXAMPLES
.Bd -literal
# root login on console at 1200 baud
console	"/usr/libexec/getty std.1200"	vt100	on secure
# dialup at 1200 baud, no root logins
ttyd0	"/usr/libexec/getty d1200"	dialup	on	# 555-1234
# Mike's terminal: hp2621
ttyh0	"/usr/libexec/getty std.9600"	hp2621-nl	on	# 457 Evans
# John's terminal: vt100
ttyh1	"/usr/libexec/getty std.9600"	vt100	on		# 459 Evans
# terminal emulate/window system
ttyv0	"/usr/new/xterm -L :0"		vs100	on window="/usr/new/Xvs100 0"
# Network pseudo ttys -- don't enable getty
ttyp0	none	network
ttyp1	none	network	off
.Ed
.Sh SEE ALSO
.Xr login 1 ,
.Xr getttyent 3 ,
.Xr ttyslot 3 ,
.Xr gettytab 5 ,
.Xr termcap 5 ,
.Xr getty 8 ,
.Xr init 8 ,
.Xr ttyflags 8
.Sh HISTORY
A
.Nm
file appeared in
.At v5 .