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< c‎ | chrono
Defined in header <time.h>
time_t time( time_t *time );

Returns the current calendar time encoded as a time_t object.


[edit] Parameters

time - pointer to a time_t object to store the time in or NULL

[edit] Return value

Current calendar time encoded as time_t object on success, (time_t)(-1) on error. If the argument is not NULL, the return value is equal to the value stored in the object pointed to by the argument.

[edit] Notes

The encoding of calendar time in time_t is unspecified, but most systems conform to POSIX specification and return a value of integral type holding the number of seconds since the Epoch. Implementations in which time_t is a 32-bit signed integer (many historical implementations) fail in the year 2038.

[edit] Example

#include <stdio.h>
#include <time.h>
#include <stdlib.h>
int main(void)
    time_t result = time(NULL);
    if (result == ((time_t)-1))
       fprintf(stderr,"time() failed in file %s at line # %d\n", __FILE__,__LINE__-3);
    printf("%s", asctime(localtime(&result)));
    printf("%d seconds since the Epoch", (int)result);
    return EXIT_SUCCESS;

Possible output:

Wed Oct  9 10:49:31 2013
1381315771 seconds since the Epoch

[edit] See also

converts time since epoch to calendar time expressed as local time
converts time since epoch to calendar time expressed as Coordinated Universal Time (UTC)
(since C11)
returns the calendar time based on a given time base