SHUTDOWN(8) BSD System Manager's Manual SHUTDOWN(8) NNAAMMEE sshhuuttddoowwnn - close down the system at a given time SSYYNNOOPPSSIISS sshhuuttddoowwnn [--] [--ffhhkkrrnn] _t_i_m_e [_w_a_r_n_i_n_g_-_m_e_s_s_a_g_e _._._.] DDEESSCCRRIIPPTTIIOONN SShhuuttddoowwnn provides an automated shutdown procedure for super-users to nicely notify users when the system is shutting down, saving them from system administrators, hackers, and gurus, who would otherwise not bother with such niceties. Available friendlinesses: --ff SShhuuttddoowwnn arranges, in the manner of fastboot(8), for the file sys- tems _n_o_t _t_o _b_e checked on reboot. --hh The system is halted at the specified _t_i_m_e when sshhuuttddoowwnn execs halt(8). --kk Kick every body off. The --kk option does not actually halt the sys- tem, but leaves the system multi-user with logins disabled (for all but super-user). --nn Prevent the normal sync(2) before stopping. --rr SShhuuttddoowwnn execs reboot(8) at the specified _t_i_m_e. _t_i_m_e _T_i_m_e is the time at which sshhuuttddoowwnn will bring the system down and may be the word _n_o_w (indicating an immediate shutdown) or specify a future time in one of two formats: _+_n_u_m_b_e_r, or _y_y_m_m_d_d_h_h_m_m, where the year, month, and day may be defaulted to the current system values. The first form brings the system down in _n_u_m_b_e_r minutes and the second at the absolute time specified. _w_a_r_n_i_n_g_-_m_e_s_s_a_g_e Any other arguments comprise the warning message that is broadcast to users currently logged into the system. -- If `--' is supplied as an option, the warning message is read from the standard input. At intervals, becoming more frequent as apocalypse approaches and start- ing at ten hours before shutdown, warning messages are displayed on the terminals of all users logged in. Five minutes before shutdown, or imme- diately if shutdown is in less than 5 minutes, logins are disabled by creating _/_e_t_c_/_n_o_l_o_g_i_n and copying the warning message there. If this file exists when a user attempts to log in, login(1) prints its contents and exits. The file is removed just before sshhuuttddoowwnn exits. At shutdown time a message is written in the system log, containing the time of shutdown, who initiated the shutdown and the reason. A terminate signal is then sent to init to bring the system down to single-user state (depending on above options). The time of the shutdown and the warning message are placed in _/_e_t_c_/_n_o_l_o_g_i_n and should be used to inform the users about when the system will be back up and why it is going down (or any- thing else). FFIILLEESS /etc/nologin tells login not to let anyone log in /fastboot tells rc(8) not to run fsck when rebooting SSEEEE AALLSSOO login(1), wall(1), fastboot(8), halt(8), reboot(8) BBAACCKKWWAARRDD CCOOMMPPAATTIIBBIILLIITTYY The hours and minutes in the second time format may be separated by a colon (``:'') for backward compatibility. HHIISSTTOORRYY The sshhuuttddoowwnn command appeared in 4.0BSD. 4th Berkeley Distribution June 5, 1993 2