// windows xp
shutdown -s -f now
// windows 7
shutdown /r /t 0
Это зависит от версии Windows.Просто выполните проверку с помощью shutdown --help и выясните, что использовать в конкретной версии.
И страницу помощи, подобранную в cygwin для моего случая (различается).
% shutdown --help
Usage: shutdown [OPTION]... time
Bring the system down.
-f, --force Forces the execution.
-s, --shutdown The system will shutdown and power off (if supported)
-r, --reboot The system will reboot.
-h, --hibernate The system will suspend to disk (if supported)
-p, --suspend The system will suspend to RAM (if supported)
--help Display this help and exit.
--version Output version information and exit.
`time' is either the time in seconds or `+' and the time in minutes or a
timestamp in the format `hh:mm' or the word "now" for an immediate action.
To reboot is the default if started as `reboot', to hibernate if started
as `hibernate', to suspend if started as `suspend', to shutdown otherwise.