There is a command shutdown in both Windows and Linux, and this
function uses it to shut down a computer.
shutdown(wait = 0)time to wait before shutting down (in seconds); passed to
Sys.sleep
The status code of system.
After the time wait has passed, R will execute shutdown -s -t
0 (for Windows) or shutdown -h now to shut down the computer.
if (interactive()) {
# when your code is extremely time-consuming, you may need this function;
# e.g. you go to sleep, and R is running long computation...
# complex graphics... and long long computation... at last,
shutdown()
# the next day you wake up, "thank you, R" :)
}