Hello:
Attached is a patch file leap_seconds.patch against util-linux-2.22.2
that allows leap seconds to be included in hwclock --show or --hctosys.
The current code uses the default UTC zonefile in reading the hardware
RTC with mktime(). This zonefile usually does not include leap
seconds. As of this date there have been a total of 25 leap seconds
added since the epoch (start of 1970). This is particularly a problem
for systems using ntp to maintain their system clocks because ntp does
take leap seconds into account. A user can specify a leap-second-aware
zonefile via /etc/localtime. By defining the environment variable
TZUTC, mktime() can be induced to use a matching UTC zonefile that
includes leap seconds. The default behavior (TZUTC undefined) is
unchanged.
Regards,
Joseph Parmelee
jparmele at wildbear.com
--- sys-utils/hwclock.c.orig 2012-12-12 14:04:22.976355744 -0600
+++ sys-utils/hwclock.c 2013-03-16 18:57:48.774606768 -0600
@@ -382,8 +382,15 @@
*/
zone = getenv("TZ"); /* remember original time zone */
if (universal) {
- /* Set timezone to UTC */
- setenv("TZ", "", TRUE);
+ /* Set timezone to UTC as defined by the environment
+ * variable TZUTC. TZUTC undefined gives the default UTC
+ * zonefile which usually does not take into account leap
+ * seconds. Define TZUTC to select your UTC zonefile which
+ * does include leap seconds. For example, with recent GNU
+ * libc's:
+ * TZUTC=:/usr/share/zoneinfo/right/UTC
+ */
+ setenv("TZ", getenv("TZUTC"), TRUE);
/*
* Note: tzset() gets called implicitly by the time code,
* but only the first time. When changing the environment
