ici :
http://www.aumha.org/a/shtrstrtz.htm
Windows XP has an actual shutdown command that can be launched from a command prompt ? and which, therefore, also can be launched from a shortcut. To see all available options for this command, click Start, click Run, and type:
SHUTDOWN /?
This command starts a 30-second countdown for a shutdown or restart, which permits you to abort it (with a shutdown -a command). It you want the command to execute, use the -t flag, which lets you set the time lapse in seconds. The examples below use a 1-second delay.
For a shortcut to RESTART Windows XP:
SHUTDOWN -r -t 01
For a shortcut to SHUT DOWN Windows XP:
SHUTDOWN -s -t 01
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