[ILUG] Setting RTC

[Niall O Broin]

I have a Toshiba 4900CT notebook - 75MHz Pentium so of course totally
obsolete as far as Windows users are concerned, but it's running Linux
just fine with 40M of RAM and a 2GB disk so I'm a happy pig, particularly
as I paid less than 300 quid S/H for it. However, I'm now trying to set
the time/date on the RTC. The BIOS setup screen doesn't offer any means of
doing this, but it can be done by booting from a DOS floppy and using the
date command. However, I won't always have that DOS floppy handy, so I'm
wondering if there is any way of changing the RTC date/time from Linux ?

Reading  Documentation/rtc.txt  I came across this

Also, if the kernel time is synchronized with an external source, the 
kernel will write the time back to the CMOS clock every 11 minutes. In 
the process of doing this, the kernel briefly turns off RTC periodic 
interrupts, so be aware of this if you are doing serious work. If you
don't synchronize the kernel time with an external source (via ntp or
whatever) then the kernel will keep its hands off the RTC, allowing you
exclusive access to the device for your applications.

but it seems that simply changing the date/time by the date command doesn't
count - I did that, waited somewhat more than 11 minutes, rebooted, and
my date change was obliterated.


Kindest regards,


Niall  O Broin		

UNIX Network Administrator 		 	nobroin at esoc.esa.de
Ground Systems Engineering Department		Ph./Fax  +49 6151 90 3619/2179
European Space Operations Centre, Darmstadt, Germany