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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.