Returns the current calendar time
#include <time.h> time_t time ( time_t *timer);
Returns the current calendar time encoded into type time_t. On error, returns -1 cast as type (time_t). To test for an error condition, compare the return value to (time_t) -1.
The time represents the time in seconds since January 1, 1970 (Universal Coordinated Time). If the timer parameter is not NULL, the current calendar time is also stored in the object pointed to by the timer parameter.