< cpp‎ | chrono‎ | c
Revision as of 22:48, 31 May 2013 by P12bot (Talk | contribs)

Defined in header <ctime>
char* asctime( const std::tm* time_ptr );

Converts given calendar time std::tm to a textual representation. The resulting string has the following format:

Www Mmm dd hh:mm:ss yyyy
  • Www - the day of the week (one of Mon, Tue, Wed, Thu, Fri, Sat, Sun).
  • Mmm - the month (one of Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec).
  • dd - the day of the month
  • hh - hours
  • mm - minutes
  • ss - seconds
  • yyyy - years

The function does not support localization.



time_ptr - pointer to a std::tm object specifying the time to print

Return value

Pointer to a static null-terminated character string holding the textual representation of date and time. The string may be shared between std::asctime and std::ctime, and may be overwritten on each invocation of any of those functions.


This function returns a pointer to static data and is not thread-safe. POSIX marks this function obsolete and recommends std::strftime instead.

The behavior is undefined if the output string would be longer than 25 characters, if timeptr->tm_wday or timeptr->tm_mon are not within the expected ranges, or if timeptr->tm_year exceeds INT_MAX-1990.

Some implementations handle timeptr->tm_mday==0 as meaning the last day of the preceding month.


#include <ctime>
#include <iostream>
int main()
    std::time_t result = std::time(NULL);
    std::cout << std::asctime(std::localtime(&result));


Tue Dec 27 16:45:52 2011

See also

converts a time_t object to a textual representation
(function) [edit]
converts a tm object to custom textual representation
(function) [edit]
formats and outputs a date/time value according to the specified format
(function template) [edit]
C documentation for asctime