I remember hearing what is probably an urban legend about the
proper way to shut down a Unix box. The console operator
is supposed to enter the sync command three times by hand
(and not on one command line like the subject shows it) to ensure
that the disk writes got out.
Now these were older boxes, and the drives may have been slow,
but this surely had to be an exageration. The story has a
great punchline though:
sync; sync; sync three times if you want to stop me ....
Mike