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+PRTimeParameters
+================
+
+A representation of time zone information.
+
+
+Syntax
+------
+
+.. code::
+
+ #include <prtime.h>
+
+ typedef struct PRTimeParameters {
+ PRInt32 tp_gmt_offset;
+ PRInt32 tp_dst_offset;
+ } PRTimeParameters;
+
+
+Description
+-----------
+
+Each geographic location has a standard time zone, and if Daylight
+Saving Time (DST) is practiced, a daylight time zone. The
+:ref:`PRTimeParameters` structure represents the local time zone
+information in terms of the offset (in seconds) from GMT. The overall
+offset is broken into two components:
+
+``tp_gmt_offset``
+ The offset of the local standard time from GMT.
+
+``tp_dst_offset``
+ If daylight savings time (DST) is in effect, the DST adjustment from
+ the local standard time. This is most commonly 1 hour, but may also
+ be 30 minutes or some other amount. If DST is not in effect, the
+ tp_dst_offset component is 0.
+
+For example, the US Pacific Time Zone has both a standard time zone
+(Pacific Standard Time, or PST) and a daylight time zone (Pacific
+Daylight Time, or PDT).
+
+- In PST, the local time is 8 hours behind GMT, so ``tp_gmt_offset`` is
+ -28800 seconds. ``tp_dst_offset`` is 0, indicating that daylight
+ saving time is not in effect.
+
+- In PDT, the clock is turned forward by one hour, so the local time is
+ 7 hours behind GMT. This is broken down as -8 + 1 hours, so
+ ``tp_gmt_offset`` is -28800 seconds, and ``tp_dst_offset`` is 3600
+ seconds.
+
+A second example is Japan, which is 9 hours ahead of GMT. Japan does not
+use daylight saving time, so the only time zone is Japan Standard Time
+(JST). In JST ``tp_gmt_offset`` is 32400 seconds, and ``tp_dst_offset``
+is 0.