windowsgoshutdown

Shutting down windows using golang code

I am making a program that automates some tedious tasks for me, after the program is done I want to shutdown windows. I know this can be done in for example C#

How can I shutdown window using golang?

Solution

  • There is no "Shutdown OS" function in the syscall package, because there is no common interface provided for that by all operating systems.

    Note: there is a syscall.Shutdown() function, but that is to shutdown a socket, and not to shutdown the operating system.

    The easiest would be to just execute the shutdown command using the os/exec package, e.g.

    if err := exec.Command("cmd", "/C", "shutdown", "/s").Run(); err != nil {
    fmt.Println("Failed to initiate shutdown:", err)
}

    The above command initiates a shutdown sequence which usually takes 1 minute to really shut down the system (and there's room to abort it with shutdown /a). You may provide different arguments to the shutdown command to not wait 1 minute but proceed immediately: shutdown /t 0 /s (execute shutdown /? to get a list of all options).

    There is also a Windows API call to shutdown the system: ExitWindowsEx(). It has 2 parameters, first is the flags to define the shutdown type (0x08 means Shuts down the system and turns off the power.), second is to provide a reason for the shutdown. To call this from Go, you can do that like this:

    user32 := syscall.MustLoadDLL("user32")
defer user32.Release()

exitwin := user32.MustFindProc("ExitWindowsEx")

r1, _, err := exitwin.Call(0x08, 0)
if r1 != 1 {
    fmt.Println("Failed to initiate shutdown:", err)
}

    But know that you need SE_SHUTDOWN_NAME privilege to call ExitWindowsEx(), else you get an error message like:

    Failed to initiate shutdown: A required privilege is not held by the client.

    See this example how to acquire the required privilege.