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clockspeed(1)		    General Commands Manual		 clockspeed(1)

NAME
       clockspeed - speed up or	slow down the local clock, continuously

SYNOPSIS
       clockspeed

DESCRIPTION
       clockspeed resets the local UNIX	clock every three seconds according to
       (1) an internal hardware	tick counter and (2) occasional	real-time mea-
       surements from a	reliable source.

       clockspeed  reads  the  real-time  measurements	from /usr/local/clock-
       speed/adjust.  Each real-time measurement  must	be  a  single  16-byte
       packet, expressed as a TAI64NA time adjustment to the local UNIX	clock.

       clockspeed  does	 not place any limits on the possible adjustments.  It
       is your responsibility to make sure that	the measurements are reliable.

       After two real-time measurements, clockspeed can	figure out the	number
       of  real	 attoseconds per tick.	It saves this number in	TAI64NA	format
       in   /usr/local/clockspeed/etc/atto,   overwriting    /usr/local/clock-
       speed/etc/atto.tmp   for	  reliability.	  It  reads  /usr/local/clock-
       speed/etc/atto when it starts up	again.

       clockspeed must be run by root.

SEE ALSO
       clockadd(1), clockview(1), sntpclock(1),	taiclock(1), adjtime(2),  get-
       timeofday(2)

								 clockspeed(1)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO

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