xref: /freebsd/libexec/getty/getty.8 (revision 0a36787e4c1fa0cf77dcf83be0867178476e372b)
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28.\"     from: @(#)getty.8	8.1 (Berkeley) 6/4/93
29.\" $FreeBSD$
30.\" "
31.Dd July 21, 2020
32.Dt GETTY 8
33.Os
34.Sh NAME
35.Nm getty
36.Nd set terminal mode
37.Sh SYNOPSIS
38.Nm
39.Oo
40.Ar type
41.Op Ar tty
42.Oc
43.Sh DESCRIPTION
44The
45.Nm
46utility is called by
47.Xr init 8
48to open and initialize the tty line, read a login name, and invoke
49.Xr login 1 .
50.Pp
51The argument
52.Ar tty
53is the special device file in
54.Pa /dev
55to open for the terminal (for example, ``ttyh0'').
56If there is no argument or the argument is
57.Sq Fl ,
58the tty line is assumed to be open as file descriptor 0.
59.Pp
60The
61.Ar type
62argument can be used to make
63.Nm
64treat the terminal line specially.
65This argument is used as an index into the
66.Xr gettytab 5
67database, to determine the characteristics of the line.
68If there is no argument, or there is no such table, the
69.Em default
70table is used.
71If there is no
72.Pa /etc/gettytab
73a set of system defaults is used.
74If indicated by the table located,
75.Nm
76will clear the terminal screen,
77print a banner heading,
78and prompt for a login name.
79Usually either the banner or the login prompt will include
80the system hostname.
81.Pp
82Most of the default actions of
83.Nm
84can be circumvented, or modified, by a suitable
85.Pa gettytab
86table.
87.Pp
88The
89.Nm
90utility can be set to timeout after some interval,
91which will cause dial up lines to hang up
92if the login name is not entered reasonably quickly.
93.Sh FILES
94.Bl -tag -width /etc/gettytab -compact
95.It Pa /etc/gettytab
96.It Pa /etc/ttys
97.El
98.Sh DIAGNOSTICS
99.Bl -diag
100.It "ttyxx: No such device or address."
101.It "ttyxx: No such file or address."
102.Pp
103A terminal which is turned
104on in the
105.Pa ttys
106file cannot be opened, likely because the requisite
107lines are either not configured into the system, the associated device
108was not attached during boot-time system configuration,
109or the special file in
110.Pa /dev
111does not exist.
112.El
113.Sh SEE ALSO
114.Xr login 1 ,
115.Xr ioctl 2 ,
116.Xr tty 4 ,
117.Xr gettytab 5 ,
118.Xr ttys 5 ,
119.Xr init 8 ,
120.Xr pstat 8
121.Sh HISTORY
122A
123.Nm
124utility appeared in
125.At v3 .
126