You did not specify what's your OS. Anyway did you look whether Win32::AdminMisc or Win32::Lanman support this?

To restart the computer you might

use Win32;
Win32::InitiateSystemShutdown(Win32::NodeName(), "", 0, 0, 1);
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(See perldoc Win32) or (if you insist on using that call):

use Win32::API;
sub EWX_LOGOFF () {0}
sub EWX_SHUTDOWN () {0x00000001}
sub EWX_REBOOT () {0x00000002}
sub EWX_FORCE () { 0x00000004}
sub EWX_POWEROFF () {0x00000008}
sub EWX_FORCEIFHUNG () {0x00000010}

$ExitWindows = new Win32::API ('kernel32','ExitWindowsEx', ['L','L'], 
+'L');
$ExitWindows->Call(EWX_REBOOT,0);
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(The code's untested, but it should work.)

Jenda
Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
   -- Rick Osborne

Edit by castaway: Closed small tag in signature