<ctime>

The <ctime> header is the C++ version of the C standard <time.h> header, which declares types and functions for working with dates and times.

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The time_t type is the fundamental representation of a date and time. The details of this type and how it encodes a date and time are implementation-defined. Unix programmers recognize this type as the number of seconds since January 1, 1970, but that is only one possible implementation.

A date and time have a secondary representation as a tm object, which breaks down a date and time into constituent parts. The parts facilitate formatting dates and times for output, or you can read a date and time, parse the parts, and build a tm object, which you can then convert to a time_t object.

This section describes the types and functions for working with dates and times. The Boost project has additional date and time classes. See Appendix B for information about Boost.

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