hi --
several people have noticed a problem with rtcwake on recent
releases built for the XO laptop. as it happens, the symptoms
exactly match this recently-reported debian bug:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=539347
i believe the issue is that rtcwake honors tm_isdst as returned
from the RTC (whose value on the XO is 0), and this incorrectly
influences the result of mktime. i suspect that the system's
knowledge of DST will usually be more correct than that of the
RTC, and so the RTC's notion should be ignored.
i've tested this with both -s and -t alarm setting options, and it
seems to do the right thing.
(a workaround, at least for the -s "relative time" case, is
simply to pass "--utc" on the rtcwake commandline. it's arguable
that rtcwake should ignore timezones when -s is used in any
case.)
paul
commit c0541b637ac9717cb931cb7ea0847756b618932c
Author: Paul Fox <pgf@xxxxxxxxxx>
Date: Thu Aug 13 10:50:50 2009 -0400
ignore the tm_isdst field returned from the RTC, since we don't use
it when setting the alarm time.
Signed-off-by: Paul Fox <pgf@xxxxxxxxxx>
diff --git a/sys-utils/rtcwake.c b/sys-utils/rtcwake.c
index 4b84373..105f5dd 100644
--- a/sys-utils/rtcwake.c
+++ b/sys-utils/rtcwake.c
@@ -156,7 +156,7 @@ static int get_basetimes(int fd)
tm.tm_mday = rtc.tm_mday;
tm.tm_mon = rtc.tm_mon;
tm.tm_year = rtc.tm_year;
- tm.tm_isdst = rtc.tm_isdst; /* stays unspecified? */
+ tm.tm_isdst = -1; /* assume the system knows better than the RTC */
rtc_time = mktime(&tm);
if (rtc_time == (time_t)-1) {
=---------------------
paul fox, pgf@xxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe util-linux-ng" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
