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# time

From cppreference.com
< c‎ | chrono

Defined in header `<time.h>` |  |
time_t time( time_t *arg ); |  |

Returns the current calendar time encoded as a time_t object, and also stores it in the time_t object pointed to by `arg` (unless `arg` is a null pointer)

### [edit] Parameters

arg | - | pointer to a time_t object where the time will be stored, or a null pointer

### [edit] Return value

Current calendar time encoded as time_t object on success, (time_t)(-1) on error. If `arg` is not a null pointer, the return value is also stored in the object pointed to by `arg`.

### [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

Run this code

    #include <stdio.h>
    #include <time.h>
    #include <stdint.h>

    int main(void)
    {
        time_t result = time(NULL);
        if(result != -1)
            printf("The current time is %s(%ju seconds since the Epoch)\n",
                   asctime(gmtime(&result)), (uintmax_t)result);
    }

Possible output:

    The current time is Fri Apr 24 15:05:25 2015
    (1429887925 seconds since the Epoch)

### [edit] References

- C11 standard (ISO/IEC 9899:2011):

  - 7.27.2.4 The time function (p: 391)

- C99 standard (ISO/IEC 9899:1999):

  - 7.23.2.4 The time function (p: 341)

- C89/C90 standard (ISO/IEC 9899:1990):

  - 4.12.2.4 The time function

### [edit] See also

localtimelocaltime_s (C11) | converts time since epoch to calendar time expressed as local time (function) [edit]
gmtimegmtime_s (C11) | converts time since epoch to calendar time expressed as Coordinated Universal Time (UTC) (function) [edit]
timespec_get (since C11) | returns the calendar time based on a given time base (function) [edit]
C++ documentation for time

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