From: David Brownell Date: Sun, 3 Feb 2008 23:34:35 +0000 (-0800) Subject: rtcwake: fix UTC time usage X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1b7c164c494090b069b92ffe9457ef2c09e63832;p=util-linux rtcwake: fix UTC time usage Timezone handling is broken in this version since it's always passing UTC time into the kernel, even on systems where the RTC uses the local timezone. I think that bug must come from bugs in how the system used to to originally develop this code handled the RTC timezone. Both RTCs should have been kept in UTC ... but only one of them was. Signed-off-by: David Brownell --- diff --git a/sys-utils/rtcwake.c b/sys-utils/rtcwake.c index 5fbd6da7..d9c9fbbf 100644 --- a/sys-utils/rtcwake.c +++ b/sys-utils/rtcwake.c @@ -187,7 +187,17 @@ static int setup_alarm(int fd, time_t *wakeup) struct tm *tm; struct rtc_wkalrm wake; - tm = gmtime(wakeup); + /* The wakeup time is in POSIX time (more or less UTC). + * Ideally RTCs use that same time; but PCs can't do that + * if they need to boot MS-Windows. Messy... + * + * When clock_mode == CM_UTC this process's timezone is UTC, + * so we'll pass a UTC date to the RTC. + * + * Else clock_mode == CM_LOCAL so the time given to the RTC + * will instead use the local time zone. + */ + tm = localtime(wakeup); wake.time.tm_sec = tm->tm_sec; wake.time.tm_min = tm->tm_min;