I do not think you will find a proper solution here (it sounds like you trying to prevent tampering with payable hours this is more of an managerial and trust issue). The main problem is that the OS reads the CMOS clock at boot up. CMOS clocks are unreliable (they generally loose time), so you are basing a system off of an unreliable source (then you end up docking someone's pay for a PC problem). I would recommend another solution, timeclocks or something of the such.

If you absolutely must go down this path look at NTP (network time protocol) to sync the time to an 'atomic' clock NTP server, then follow Chady's and cLive ;-)'s suggestions.

grep
grep> chown linux:users /world

In reply to Re: Perl reading clock changes by grep
in thread Perl reading clock changes by NEOGrafix

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