On linux you have to edit the file "/etc/inittab" and change from
Qt Code: 
  1. ca:12345:ctrlaltdel:/sbin/shutdown -t1 -a -r now
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to
Qt Code: 
  1. # ca:12345:ctrlaltdel:/sbin/shutdown -t1 -a -r now
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After this you either boot the system or type on the console:
Qt Code: 
  1. init q
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This could also be done with QFile, QRegExp and QProcess

Best Regards
NoRulez