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conflicting packages
CLOCK(8) | System Manager's Manual | CLOCK(8) |
NAME¶
clock - manipulate the CMOS clockSYNOPSIS¶
clock [-u] [-rwsa] [ -v]DESCRIPTION¶
clock manipulates the CMOS clock in variaous ways, allowing it to be read or written, and allowing synchronization between the CMOS clock and the kernel's version of the system time.OPTIONS¶
- -u
- indicates that the CMOS clock is set to universal time
- -r
- read CMOS clock and print the result to stdout
- -w
- write the system time into the CMOS clock
- -s
- set the system time from the CMOS clock
- -a
- set the system time from the CMOS clock, adjusting the time to correct for systematic error, and writting it back into the CMOS clock.
- -v
- print version number
- 0(e1.
- the correction in seconds per day (for example, if your clock runs 5 seconds fast each day, the first number should read -5.0),
- 0(e1.
- time when clock was last used, in seconds since 1/1/1970,
- 0(e1.
- the remaining part of a second that was left over after the last adjustment.
- 0(e1.
- create a file /etc/adjtime containing as the first and only line: '0.0 0 0.0',
- 0(e1.
- run clock -au or clock -a, depending on whether your CMOS is in Universal or Local Time. This updates the second number,
- 0(e1.
- set your system time using the date command,
- 0(e1.
- update your CMOS time using clock -wu or clock -w,
- 0(e1.
- replace the first number in /etc/adjtime by your correction,
- 0(e1.
- put the command clock -au or clock -a in your /etc/rc.local, or let cron start it regularly.
FILES¶
/etc/adjtime /etc/rc.localAUTHORS¶
- V1.0
- Charles Hedrick, hedrick@cs.rutgers.edu, Apr 1992
- V1.1
- Modified for clock adjustments, Rob Hooft, hooft@chem.ruu.nl, Nov 1992
- V1.2
- Patches by Harald Koenig, koenig@nova.tat.physik.uni-tuebingen.de, applied by Rob Hooft, hooft@EMBL-Heidelberg.DE, Oct 1993
- V1.3
- Changes from alan@spri.levels.unisa.edu.au (Alan Modra)
- V1.4
- Fix for years > 2000 alan@SPRI.Levels.UniSA.Edu.Au (Alan Modra), and added -v option to print version faith@cs.unc.edu, Feb 1995.
- V1.4a
- Converted to be compatible with the SPARC /dev/rtc driver Tom Dyas (tdyas@eden.rutgers.edu), Aug 1996
- V1.4b
- Adapted for Power Macintosh by Paul Mackerras, Dec 1996