2.9BSD/usr/man/cat8/shutdown.8

SHUTDOWN(8)         UNIX Programmer's Manual          SHUTDOWN(8)

NAME
     shutdown - close down the system at a given time

SYNOPSIS
     /etc/shutdown [ -k ] [ -r ] [ -h ] time [ warning-message
     ... ]

DESCRIPTION
     _S_h_u_t_d_o_w_n provides an automated shutdown procedure which a
     super-user can use to notify users nicely when the system is
     shutting down, saving them from system administrators, hack-
     ers, and gurus, who would otherwise not bother with
     niceties.

     _T_i_m_e is the time at which _s_h_u_t_d_o_w_n will bring the system
     down and may take two formats: +number and hour:min.  The
     first form brings the system down in _n_u_m_b_e_r minutes and the
     second brings the system down at the time of day indicated
     (as a 24-hour clock).

     At intervals which get closer together as apocalypse
     approaches, warning messages are displayed at the terminals
     of all users on the system.  Five minutes before shutdown,
     or immediately if shutdown is in less than 5 minutes, logins
     are disabled by creating /etc/nologin and writing a message
     there.  If this file exists when a user logs in, _l_o_g_i_n(1)
     prints its contents and exits.  The file is removed just
     before _s_h_u_t_d_o_w_n exits.

     At shutdown time a message is written in the file
     /usr/adm/shutdownlog, containing the time of shutdown, who
     ran shutdown and the reason.  Then a terminate signal is
     sent at _i_n_i_t to bring the system down to single-user state.
     Alternatively, if -r, -h, or -k was used, then _s_h_u_t_d_o_w_n will
     exec _r_e_b_o_o_t(8) (in the first two cases) or avoid shutting
     the system down (in the latter case).  (If it isn't obvious,
     -k is to make people _t_h_i_n_k the system is going down!)

     The time of the shutdown and the warning message are placed
     in /etc/nologin and should be used to inform the users about
     when the system will be back up and why it is going down (or
     anything else).

FILES
     /etc/nologin        tells login not to let anyone log in
     /usr/adm/shutdownloglog file for succesful shutdowns.

SEE ALSO
     login(1), reboot(8)

BUGS
     Only allows you to kill the system between now and 23:59 if

Printed 8/2/83                                                  1

SHUTDOWN(8)         UNIX Programmer's Manual          SHUTDOWN(8)

     you use the absolute time for shutdown.

     Times to shutdown are not nice and round, i.e. ``shutdown in
     18 seconds''.

Printed 8/2/83                                                  2