# phpman > man > SHUTDOWN(8)

[SHUTDOWN(8)](https://www.chedong.com/phpMan.php/man/SHUTDOWN/8/markdown)                                   shutdown                                   [SHUTDOWN(8)](https://www.chedong.com/phpMan.php/man/SHUTDOWN/8/markdown)



## NAME
       shutdown - Halt, power-off or reboot the machine

## SYNOPSIS
       **shutdown** [OPTIONS...] [TIME] [WALL...]

## DESCRIPTION
       **shutdown** may be used to halt, power-off or reboot the machine.

       The first argument may be a time string (which is usually "now"). Optionally, this may be
       followed by a wall message to be sent to all logged-in users before going down.

       The time string may either be in the format "hh:mm" for hour/minutes specifying the time to
       execute the shutdown at, specified in 24h clock format. Alternatively it may be in the syntax
       "+m" referring to the specified number of minutes m from now.  "now" is an alias for "+0",
       i.e. for triggering an immediate shutdown. If no time argument is specified, "+1" is implied.

       Note that to specify a wall message you must specify a time argument, too.

       If the time argument is used, 5 minutes before the system goes down the /run/nologin file is
       created to ensure that further logins shall not be allowed.

## OPTIONS
       The following options are understood:

### --help
           Print a short help text and exit.

### -H --halt
           Halt the machine.

### -P --poweroff
           Power-off the machine (the default).

### -r --reboot
           Reboot the machine.

### -h
           Equivalent to **--poweroff**, unless **--halt** is specified.

### -k
           Do not halt, power-off, reboot, just write wall message.

### --no-wall
           Do not send wall message before halt, power-off, reboot.

### -c
           Cancel a pending shutdown. This may be used to cancel the effect of an invocation of
           **shutdown** with a time argument that is not "+0" or "now".

## EXIT STATUS
       On success, 0 is returned, a non-zero failure code otherwise.

## SEE ALSO
       [**systemd**(1)](https://www.chedong.com/phpMan.php/man/systemd/1/markdown), [**systemctl**(1)](https://www.chedong.com/phpMan.php/man/systemctl/1/markdown), [**halt**(8)](https://www.chedong.com/phpMan.php/man/halt/8/markdown), [**wall**(1)](https://www.chedong.com/phpMan.php/man/wall/1/markdown)



systemd 249                                                                              [SHUTDOWN(8)](https://www.chedong.com/phpMan.php/man/SHUTDOWN/8/markdown)