1.\" Copyright (c) 1980, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.roff% 5.\" 6.\" @(#)login.1 8.2 (Berkeley) 05/05/94 7.\" 8.Dd 9.Dt LOGIN 1 10.Os BSD 4 11.Sh NAME 12.Nm login 13.Nd log into the computer 14.Sh SYNOPSIS 15.Nm login 16.Op Fl fp 17.Op Fl h Ar hostname 18.Op Ar user 19.Sh DESCRIPTION 20The 21.Nm login 22utility logs users (and pseudo-users) into the computer system. 23.Pp 24If no user is specified, or if a user is specified and authentication 25of the user fails, 26.Nm login 27prompts for a user name. 28Authentication of users is done via passwords. 29.Pp 30The options are as follows: 31.Bl -tag -width Ds 32.It Fl f 33The 34.Fl f 35option is used when a user name is specified to indicate that proper 36authentication has already been done and that no password need be 37requested. 38This option may only be used by the super-user or when an already 39logged in user is logging in as themselves. 40.It Fl h 41The 42.Fl h 43option specifies the host from which the connection was received. 44It is used by various daemons such as 45.Xr telnetd 8 . 46This option may only be used by the super-user. 47.It Fl p 48By default, 49.Nm login 50discards any previous environment. 51The 52.Fl p 53option disables this behavior. 54.El 55.Pp 56If the file 57.Pa /etc/nologin 58exists, 59.Nm login 60dislays its contents to the user and exits. 61This is used by 62.Xr shutdown 8 63to prevent users from logging in when the system is about to go down. 64.Pp 65Immediately after logging a user in, 66.Nm login 67displays the system copyright notice, the date and time the user last 68logged in, the message of the day as well as other information. 69If the file 70.Dq Pa .hushlogin 71exists in the user's home directory, all of these messages are suppressed. 72This is to simplify logins for non-human users, such as 73.Xr uucp 1 . 74.Nm Login 75then records an entry in the 76.Xr wtmp 5 77and 78.Xr utmp 5 79files and executes the user's command interpretor. 80.Pp 81Login enters information into the environment (see 82.Xr environ 7 ) 83specifying the user's home directory (HOME), command interpreter (SHELL), 84search path (PATH), terminal type (TERM) and user name (both LOGNAME and 85USER). 86.Pp 87The standard shells, 88.Xr csh 1 89and 90.Xr sh 1 , 91do not fork before executing the 92.Nm login 93utility. 94.Sh FILES 95.Bl -tag -width /var/mail/userXXX -compact 96.It Pa /etc/motd 97message-of-the-day 98.It Pa /etc/nologin 99disallows logins 100.It Pa /var/run/utmp 101current logins 102.It Pa /var/log/lastlog 103last login account records 104.It Pa /var/log/wtmp 105login account records 106.It Pa /var/mail/user 107system mailboxes 108.It Pa \&.hushlogin 109makes login quieter 110.El 111.Sh SEE ALSO 112.Xr chpass 1 , 113.Xr passwd 1 , 114.Xr rlogin 1 , 115.Xr getpass 3 , 116.Xr utmp 5 , 117.Xr environ 7 , 118.Sh HISTORY 119A 120.Nm login 121appeared in 122.At v6 . 123