shutdown(8) [ultrix man page]
shutdown(8) System Manager's Manual shutdown(8) Name shutdown - close down the system at a given time Syntax /etc/shutdown [ -k ] [ -r ] [ -h ] [ -o ] time [ warning-message ... ] Description The command provides an automated shutdown procedure that a superuser can use to notify users when the system is shutting down. The time is the time at which will bring the system down. It may be the word `now', indicating an immediate shutdown, or specify a future time in one of two formats: + number or hour : min. The first form brings the system down in number minutes. The second brings the system down at the time of day indicated, using a 24-hour clock format. At intervals which get shorter as shutdown nears, warning messages are displayed at the terminals of all users on the system. Warning mes- sages are also sent to users who are logged in to a remote system that has mounted a file system or directory from the local system using NFS. Five minutes before shutdown, or immediately if shutdown is timed for less than five minutes, logins are disabled by creating and writing a message there. If this file exists when a user attempts to log in, prints its contents and exits. The file is removed just before exits. At shutdown time, a message is written in the file This message contains the time of shutdown, who ran shutdown, and the reason. Then, a terminate signal is sent at to bring the system to single-user state. If the or options are used, then executes or avoids shutting the system down (respectively). The option is for use by only. It indicates to that it is being called by and not to return to the user. You should place the time of the shutdown and the warning message in Use the message to inform the users about when the system will be back up and why it is going down. Restrictions You can kill the system only between now and 23:59, if you use the absolute time for shutdown. Files Tells login not to let anyone log in Log file for successful shutdowns See Also login(1), wall(1), halt(8), opser(8), reboot(8), rwalld(8c) shutdown(8)
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SHUTDOWN(8) System Manager's Manual SHUTDOWN(8) NAME
shutdown - close down the system at a given time SYNOPSIS
shutdown [ -k ] [ -r ] [ -h ] [ -f ] [ -n ] time [ warning-message ... ] DESCRIPTION
Shutdown provides an automated shutdown procedure which a super-user can use to notify users nicely when the system is shutting down, sav- ing them from system administrators, hackers, and gurus, who would otherwise not bother with niceties. Time is the time at which shutdown will bring the system down and may be the word now (indicating an immediate shutdown) or specify a future time in one of two formats: +number and hour:min. The first form brings the system down in number 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 sys- tem. 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 attempts to log in, login(1) prints its contents and exits. The file is removed just before shutdown exits. At shutdown time a message is written in the system log, containing the time of shutdown, who ran shutdown and the reason. Then a termi- nate signal is sent to init to bring the system down to single-user state. Alternatively, if -r, -h, or -k was used, then shutdown will exec reboot(8), halt(8), or avoid shutting the system down (respectively). (If it isn't obvious, -k is to make people think the system is going down!) With the -f option, shutdown arranges, in the manner of fastboot(8), that when the system is rebooted the file systems will not be checked. The -n option prevents the normal sync(2) before stopping. 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 SEE ALSO
login(1), reboot(8), fastboot(8) BUGS
Only allows you to kill the system between now and 23:59 if you use the absolute time for shutdown. 4th Berkeley Distribution November 16, 1996 SHUTDOWN(8)