Implement new option --predict that predicts what the RTC will read
at a time given by the --date option. This is useful for example if
you need to setup an RTC wakeup time to distant future and want to
account for the RTC drift.
Signed-off-by: Timo Juhani Lindfors <timo.lindfors@iki.fi>
Signed-off-by: Karel Zak <kzak@redhat.com>
Since the system clock time is already set from the hardware clock by the
kernel (when compiled with CONFIG_RTC_HCTOSYS), there's no particular need to
read the hardware clock again.
This option sets the system clock using itself as a reference if the
hardware clock was in local time. The resulting system clock time
is in UTC, with the kernel timezone set to the difference.
[kzak@redhat.com: - fix the condition that controls read_adjtime() call]
Signed-off-by: Scott James Remnant <scott@ubuntu.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
The patch to allow "hwclock --rtc /dev/rtc1" and so on,
since "/dev/rtc" may not be there and "/dev/rtc0" may not be
the right answer either.
The "--rtc" is compatible with next Bryan Henderson's hwclock
versions.
Signed-off-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Karel Zak <kzak@redhat.com>