57 lines
1.5 KiB
Markdown
57 lines
1.5 KiB
Markdown
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# tz module
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This is a simple module that parses timezone files as found on unix systems. It is oriented around converting the current time. It can convert other times, but it is
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rather less efficient as it maintains only a single cached entry in memory.
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On my linux system, these files can be found in `/usr/share/zoneinfo`.
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## tz.setzone()
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This sets the timezone to be used in subsequent conversions
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#### Syntax
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`tz.setzone(timezone)`
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#### Parameters
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- `timezone` this is the timezone string. It must correspond to a file in the file system which is named timezone.zone.
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#### Returns
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true if the zone exists in the file system.
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## tz.getoffset()
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This gets the offset (in seconds) of the time passed as the argument.
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#### Syntax
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`tz.getoffset(time)`
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#### Parameters
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- `time` the number of seconds since the epoch. This is the same value as used by the `sntp` module.
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#### Returns
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- The number of seconds of offset. West of Greenwich is negative.
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- The start time (in epoch seconds) of this offset.
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- The end time (in epoch seconds) of this offset.
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#### Example
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```
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tz = require('tz')
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tz.setzone('eastern')
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sntp.sync(nil, function(now)
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local tm = rtctime.epoch2cal(now + tz.getoffset(now))
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print(string.format("%04d/%02d/%02d %02d:%02d:%02d", tm["year"], tm["mon"], tm["day"], tm["hour"], tm["min"], tm["sec"]))
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end)
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```
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## tz.getzones()
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This returns a list of the available timezones in the file system.
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#### Syntax
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`tz.getzones()`
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#### Returns
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A list of timezones.
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