Hi,

> > and nvram-wakeup only works on some modern mainborads.
> 
> My point is: if there are ways to tell a machine "shutdown now and power
> up automatically at time X" we should have a kernel interface that just
> does this. Other architectures might have the same operation, but implemented
> completely different. A quick search seems to suggest that there is not
> even a stanard way to store the alarm time in the rtc nvram on i386, but
> that it is bios dependend.

FYI, the ACPI spec defines RTC (real time clock) wakeup event from
sleep states (S1-S4).  That's what I think is used for Windows TV
recording software.
According to the spec, the soft-off state (S5) is not a sleep state
and is not expected to wake on alarm, however.

If you're interested, please refer ACPI 3.0 spec 4.7.2.4 "Real Time Clock
Alarm".

---
Takayoshi Kochi