std::chrono::sys_info

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Date and time library

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std::chrono::sys_info

Non-member functions
operator<<
Helper classes
formatter<std::chrono::sys_info>

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Defined in header`<chrono>`
struct sys_info;		(since C++20)

The classsys_info describes time zone information associated with a time zone at a particular point in time (represented as either astd::chrono::sys_time or astd::chrono::local_time). This is a low-level data structure typically not used directly by user code.

[edit]Member objects

Member object	Type
`begin`,`end`	std::chrono::sys_seconds
`offset`	std::chrono::seconds
`save`	std::chrono::minutes
`abbrev`	std::string

Thebegin andend data members indicate the range -[begin, end) - in which theoffset andabbrev are in effect for the time zone associated with thissys_info.

Theoffset andabbrev data member indicate the UTC offset and time zone abbreviation, respectively, in effect for the associated time zone andstd::chrono::time_point. Note that time zone abbreviations are not unique.

Thesave data member, if nonzero, indicates that the time zone is on daylight saving time at the specified time point. In this case,offset- save is a suggestion of what offset this time zone might use if it were off daylight saving time. However, this information is not authoritative: the only way to ascertain the actual offset is to query the time zone with a time point that is actually off daylight savings time (i.e. returns asys_info such thatsave== 0min).