NAME

     readclock - read the AT's real time clock


SYNOPSIS

     readclock [-nwW2]


DESCRIPTION

     Readclock reads the  AT's  real  time  clock  and  sets  the
     machine's  time.   It  is  usually  the second thing done in
     /etc/rc, the first thing is setting the time zone by  sourc-
     ing  /etc/profile.   This means that the clock is assumed to
     tell the wall clock time.  If you want to run the  clock  in
     GMT then you can put TZ=GMT (or any other TZ value) in front
     of the readclock command.


OPTIONS

     -n   Play-act, don't set the time nor change the calibration
          data, just show what would be done.

     -w   Write the current time to the CMOS  clock.   Dangerous,
          see BUGS.  Don't forget to use TZ=GMT in front of read-
          clock if the clock should run in GMT.

     -W   Like -w, but also sets the status registers of the CMOS
          clock  to  their proper values.  (For if the clock sud-
          denly runs at an odd pace or has stopped and  the  BIOS
          doesn't repair it.)

     -2,  Add 20 to any year before 2000.   If  your  CMOS  clock
          year  can't  run past 2000, then you can set it to 1980
          and use -2 to correct the year.  Together with  -w  the
          year minus 20 is written to the clock.


FILES

     /etc/profile        Timezone and other shell  initialization
                         code.


SEE ALSO

     date(1), utime(1).


BUGS

     Reported to not work on some AT's.

     May mess up the clock royally when setting it (-w).  Only if
     you have a very standard AT and you are not afraid of having
     your CMOS setup reset to the default with a "checksum error"
     should  you use readclock to set the time of the CMOS clock.
     You have been warned.


AUTHOR

     Kees J. Bot (kjb@cs.vu.nl)