std::tm

From cppreference.com

Structure holding a calendar date and time broken down into its components.


int tm_sec	seconds after the minute – [0, 60]^{[note 1]} (public member object)

int tm_min	minutes after the hour – [0, 59] (public member object)

int tm_hour	hours since midnight – [0, 23] (public member object)

int tm_mday	day of the month – [1, 31] (public member object)

int tm_mon	months since January – [0, 11] (public member object)

int tm_year	years since 1900 (public member object)

int tm_wday	days since Sunday – [0, 6] (public member object)

int tm_yday	days since January 1 – [0, 365] (public member object)

int tm_isdst	Daylight Saving Time flag. The value is positive if DST is in effect, zero if not and negative if no information is available (public member object)


localtime	converts time since epoch to calendar time expressed as local time (function)

gmtime	converts time since epoch to calendar time expressed as Universal Coordinated Time (function)

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