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Defined in header <ctime> | ||
std::time_t time(std::time_t* arg); | ||
Returns the current calendar time encoded as astd::time_t object, and also stores it in the object pointed to byarg, unlessarg is a null pointer.
Contents |
| arg | - | pointer to astd::time_t object to store the time, or a null pointer |
Current calendar time encoded asstd::time_t object on success,(std::time_t)(-1) on error. Ifarg is not null, the return value is also stored in the object pointed to byarg.
The encoding of calendar time instd::time_t is unspecified, but most systems conform to thePOSIX specification and return a value of integral type holding 86400 times the number of calendar days sincethe Epoch plus the number of seconds that have passed since the last midnight UTC. Most notably, POSIX time does not (and can not) take leap seconds into account, so that this integral value is not equal to the number ofS.I. seconds that have passed since the epoch, but rather is reduced with the number of leap seconds that have occurred since the epoch. Implementations in whichstd::time_t is a 32-bit signed integer (many historical implementations) fail in the year2038.
#include <ctime>#include <iostream> int main(){std::time_t result= std::time(nullptr);std::cout<<std::asctime(std::localtime(&result))<< result<<" seconds since the Epoch\n";}
Possible output:
Wed Sep 21 10:27:52 20111316615272 seconds since the Epoch
(C++17) | returns the calendar time in seconds and nanoseconds based on a given time base (function)[edit] |
| converts time since epoch to calendar time expressed as local time (function)[edit] | |
| converts time since epoch to calendar time expressed as Universal Coordinated Time (function)[edit] | |
(C++11) | wall clock time from the system-wide realtime clock (class)[edit] |
C documentation fortime | |
