std::time
| Defined in header <ctime> | ||
|---|---|---|
| std::time_t time( std::time_t* arg ); | 
Returns the current calendar time encoded as a std::time_t object, and also stores it in the object pointed to by arg, unless arg is a null pointer.
Parameters
| arg | - | pointer to a std::time_tobject to store the time, or a null pointer | 
Return value
Current calendar time encoded as std::time_t object on success, (std::time_t)(-1) on error. If arg is not null, the return value is also stored in the object pointed to by arg.
Notes
The encoding of calendar time in std::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 std::time_t is a 32-bit signed integer (many historical implementations) fail in the year 2038.
Example
#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";
}Output:
Wed Sep 21 10:27:52 2011 1316615272 seconds since the Epoch
See also
| converts time since epoch to calendar time expressed as local time (function) | |
| converts time since epoch to calendar time expressed as Universal Coordinated Time (function) | |
| (C++11) | wall clock time from the system-wide realtime clock (class) | 
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