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Re: Year 2000

There is a year-2000 problem we know of that is connected to your PC's
BIOS and clock chip. The BIOS and clock chip of many systems store a
two-digit year. This is a separate issue from the Linux kernel clock,
which is all software. Linux uses a program to read the hardware clock
into the software one at boot time, and then does not refer to the
hardware clock again except to set it or to measure its drift over time
and correct for that. A patch to the hardware clock reader is necessary
to achieve year-2000 compliance even if your BIOS and clock chip think
it's 1900. We expect to be distributing this with Debian 2.0 . Since we
publish all source code, anyone can fix it sooner if necessary.

Unix and Linux store time as a count of seconds since New Year's day
1970 in a signed 32-bit integer. This was chosen to make the system
time-zone-independent. This form of time storage does not have a
year-2000 problem, but it will overflow in the year 2036. By that time
we expect to have converted to a 64-bit variable, which will not
overflow for around 274877906944 years. Hopefully, by that time
something better than Unix will have come along.

Several other year-2000 issues have already been found and repaired.
We've run our systems with the clock set to various future dates to test
them. We can't guarantee there are not any problems left, but we are sure
they would be minor ones, and rapidly repaired. Because we publish all
source code, you are guaranteed that you can get any problems fixed quickly.


	Bruce Perens
Can you get your operating system fixed when you need it?
Linux - the supportable operating system. http://www.debian.org/support.html
Bruce Perens K6BP   bruce@debian.org   NEW PHONE NUMBER: 510-620-3502

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