std::put_time
<iomanip> 
 /*unspecified*/ put_time( const std::tm * tmb, const CharT* fmt );
When used in an expression out << put_time(tmb, fmt), converts the date and time information from a given calendar time tmb to a character string according to format string fmt, as if by calling std::strftime , std::wcsftime , or analog (depending on CharT), according to the std::time_put  facet of the locale currently imbued in the output stream out.
[edit] Parameters
CharT string specifying the format of conversion
[edit] Format string
The format string consists of zero or more conversion specifiers and ordinary characters (except %). All ordinary characters, including the terminating null character, are copied to the output string without modification. Each conversion specification begins with % character, optionally followed by E or O modifier (ignored if unsupported by the locale), followed by the character that determines the behavior of the specifier. The following format specifiers are available:
| Conversion specifier | Explanation | Used fields | 
|---|---|---|
| % | writes literal %. The full conversion specification must be%%. | |
| n(C++11) | writes newline character | |
| t(C++11) | writes horizontal tab character | |
| Year | ||
| Y | writes year as a decimal number, e.g. 2017 | tm_year | 
| EY(C++11) | writes year in the alternative representation, e.g.平成23年 (year Heisei 23) instead of 2011年 (year 2011) in ja_JP locale | tm_year | 
| y | writes last 2 digits of year as a decimal number (range [00,99]) | tm_year | 
| Oy(C++11) | writes last 2 digits of year using the alternative numeric system, e.g. 十一 instead of 11 in ja_JP locale | tm_year | 
| Ey(C++11) | writes year as offset from locale's alternative calendar period %EC(locale-dependent) | tm_year | 
| C(C++11) | writes first 2 digits of year as a decimal number (range [00,99]) | tm_year | 
| EC(C++11) | writes name of the base year (period) in the locale's alternative representation, e.g. 平成 (Heisei era) in ja_JP | tm_year | 
| G(C++11) | writes ISO 8601 week-based year, i.e. the year that contains the specified week. In ISO 8601 weeks begin with Monday and the first week of the year must satisfy the following requirements: 
 | tm_year,tm_wday,tm_yday | 
| g(C++11) | writes last 2 digits of ISO 8601 week-based year, i.e. the year that contains the specified week (range [00,99]).In ISO 8601 weeks begin with Monday and the first week of the year must satisfy the following requirements: 
 | tm_year,tm_wday,tm_yday | 
| Month | ||
| b | writes abbreviated month name, e.g. Oct(locale dependent) | tm_mon | 
| h(C++11) | synonym of b | tm_mon | 
| B | writes full month name, e.g. October(locale dependent) | tm_mon | 
| m | writes month as a decimal number (range [01,12]) | tm_mon | 
| Om(C++11) | writes month using the alternative numeric system, e.g. 十二 instead of 12 in ja_JP locale | tm_mon | 
| Week | ||
| U | writes week of the year as a decimal number (Sunday is the first day of the week) (range [00,53]) | tm_year,tm_wday,tm_yday | 
| OU(C++11) | writes week of the year, as by %U, using the alternative numeric system, e.g. 五十二 instead of 52 in ja_JP locale | tm_year,tm_wday,tm_yday | 
| W | writes week of the year as a decimal number (Monday is the first day of the week) (range [00,53]) | tm_year,tm_wday,tm_yday | 
| OW(C++11) | writes week of the year, as by %W, using the alternative numeric system, e.g. 五十二 instead of 52 in ja_JP locale | tm_year,tm_wday,tm_yday | 
| V(C++11) | writes ISO 8601 week of the year (range [01,53]).In ISO 8601 weeks begin with Monday and the first week of the year must satisfy the following requirements: 
 | tm_year,tm_wday,tm_yday | 
| OV(C++11) | writes week of the year, as by %V, using the alternative numeric system, e.g. 五十二 instead of 52 in ja_JP locale | tm_year,tm_wday,tm_yday | 
| Day of the year/month | ||
| j | writes day of the year as a decimal number (range [001,366]) | tm_yday | 
| d | writes day of the month as a decimal number (range [01,31]) | tm_mday | 
| Od(C++11) | writes zero-based day of the month using the alternative numeric system, e.g. 二十七 instead of 27 in ja_JP locale Single character is preceded by a space. | tm_mday | 
| e(C++11) | writes day of the month as a decimal number (range [1,31]).Single digit is preceded by a space. | tm_mday | 
| Oe(C++11) | writes one-based day of the month using the alternative numeric system, e.g. 二十七 instead of 27 in ja_JP locale Single character is preceded by a space. | tm_mday | 
| Day of the week | ||
| a | writes abbreviated weekday name, e.g. Fri(locale dependent) | tm_wday | 
| A | writes full weekday name, e.g. Friday(locale dependent) | tm_wday | 
| w | writes weekday as a decimal number, where Sunday is 0(range[0-6]) | tm_wday | 
| Ow(C++11) | writes weekday, where Sunday is 0, using the alternative numeric system, e.g. 二 instead of 2 in ja_JP locale | tm_wday | 
| u(C++11) | writes weekday as a decimal number, where Monday is 1(ISO 8601 format) (range[1-7]) | tm_wday | 
| Ou(C++11) | writes weekday, where Monday is 1, using the alternative numeric system, e.g. 二 instead of 2 in ja_JP locale | tm_wday | 
| Hour, minute, second | ||
| H | writes hour as a decimal number, 24 hour clock (range [00-23]) | tm_hour | 
| OH(C++11) | writes hour from 24-hour clock using the alternative numeric system, e.g. 十八 instead of 18 in ja_JP locale | tm_hour | 
| I | writes hour as a decimal number, 12 hour clock (range [01,12]) | tm_hour | 
| OI(C++11) | writes hour from 12-hour clock using the alternative numeric system, e.g. 六 instead of 06 in ja_JP locale | tm_hour | 
| M | writes minute as a decimal number (range [00,59]) | tm_min | 
| OM(C++11) | writes minute using the alternative numeric system, e.g. 二十五 instead of 25 in ja_JP locale | tm_min | 
| S | writes second as a decimal number (range [00,60]) | tm_sec | 
| OS(C++11) | writes second using the alternative numeric system, e.g. 二十四 instead of 24 in ja_JP locale | tm_sec | 
| Other | ||
| c | writes standard date and time string, e.g. Sun Oct 17 04:41:13 2010(locale dependent) | all | 
| Ec(C++11) | writes alternative date and time string, e.g. using 平成23年 (year Heisei 23) instead of 2011年 (year 2011) in ja_JP locale | all | 
| x | writes localized date representation (locale dependent) | all | 
| Ex(C++11) | writes alternative date representation, e.g. using 平成23年 (year Heisei 23) instead of 2011年 (year 2011) in ja_JP locale | all | 
| X | writes localized time representation, e.g. 18:40:20 or 6:40:20 PM (locale dependent) | all | 
| EX(C++11) | writes alternative time representation (locale dependent) | all | 
| D(C++11) | equivalent to "%m/%d/%y" | tm_mon,tm_mday,tm_year | 
| F(C++11) | equivalent to "%Y-%m-%d" (the ISO 8601 date format) | tm_mon,tm_mday,tm_year | 
| r(C++11) | writes localized 12-hour clock time (locale dependent) | tm_hour,tm_min,tm_sec | 
| R(C++11) | equivalent to "%H:%M" | tm_hour,tm_min | 
| T(C++11) | equivalent to "%H:%M:%S" (the ISO 8601 time format) | tm_hour,tm_min,tm_sec | 
| p | writes localized a.m. or p.m. (locale dependent) | tm_hour | 
| z(C++11) | writes offset from UTC in the ISO 8601 format (e.g. -0430), or no characters if the time zone information is not available | tm_isdst | 
| Z | writes locale-dependent time zone name or abbreviation, or no characters if the time zone information is not available | tm_isdst | 
[edit] Return value
An object of unspecified type such that
-  if out is an object of type std::basic_ostream <CharT, Traits>, the expression out << put_time(tmb, fmt)
- has type std::basic_ostream <CharT, Traits>&
- has value out
- behaves as if it called f(out, tmb, fmt)
 
where the function f is defined as:
template<class CharT, class Traits> void f(std::basic_ios <CharT, Traits>& str, const std::tm * tmb, const CharT* fmt) { using Iter = std::ostreambuf_iterator <CharT, Traits>; using TimePut = std::time_put <CharT, Iter>; const TimePut& tp = std::use_facet <TimePut>(str.getloc()); const Iter end = tp.put(Iter(str.rdbuf()), str, str.fill(), tmb, fmt, fmt + Traits::length(fmt)); if (end.failed()) str.setstate(std::ios_base::badbit ); }
[edit] Example
#include <ctime> #include <iomanip> #include <iostream> int main() { std::time_t t = std::time (nullptr); std::tm tm = *std::localtime (&t); std::cout.imbue(std::locale ("ru_RU.utf8")); std::cout << "ru_RU: " << std::put_time(&tm, "%c %Z") << '\n'; std::cout.imbue(std::locale ("ja_JP.utf8")); std::cout << "ja_JP: " << std::put_time(&tm, "%c %Z") << '\n'; }
Possible output:
ru_RU: Ср. 28 дек. 2011 10:21:16 EST ja_JP: 2011年12月28日 10時21分16秒 EST