coreutils: Combined date and time of day items
29.5 Combined date and time of day items
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The ISO 8601 date and time of day extended format consists of an ISO
8601 date, a âTâ character separator, and an ISO 8601 time of day. This
format is also recognized if the âTâ is replaced by a space.
In this format, the time of day should use 24-hour notation.
Fractional seconds are allowed, with either comma or period preceding
the fraction. ISO 8601 fractional minutes and hours are not supported.
Typically, hosts support nanosecond timestamp resolution; excess
precision is silently discarded.
Here are some examples:
2012-09-24T20:02:00.052-05:00
2012-12-31T23:59:59,999999999+11:00
1970-01-01 00:00Z