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std::get_time

Defined in header `<iomanip>`
template< class CharT > /unspecified/ get_time( std::tm* tmb, const CharT* fmt );		(since C++11)

When used in an expression in >> get_time(tmb, fmt), parses the character input as a date/time value according to format string fmt according to the std::time_get facet of the locale currently imbued in the input stream in. The resultant value is stored in a std::tm object pointed to by tmb.

Parameters

tmb - valid pointer to the std::tm object where the result will be stored

fmt

pointer to a null-terminated CharT string specifying the conversion format

The format string consists of zero or more conversion specifiers, whitespace characters, and ordinary characters (except %). Each ordinary character is expected to match one character in the input stream in case-insensitive comparison. Each whitespace character matches arbitrary whitespace in the input string. 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 format specifiers match the POSIX function strptime():

Conversion specifier	Explanation	Writes to fields
`%`	matches a literal `%`. The full conversion specification must be `%%`.	(none)
`t`	matches any whitespace.	(none)
`n`	matches any whitespace.	(none)
Year
`Y`	parses full year as a 4 digit decimal number, leading zeroes permitted but not required	`tm_year`
`EY`	parses year in the alternative representation, e.g.平成23年 (year Heisei 23) which writes 2011 to tm_year in ja_JP locale	`tm_year`
`y`	parses last 2 digits of year as a decimal number. Range `[69,99]` results in values 1969 to 1999, range `[00,68]` results in 2000-2068	`tm_year`
`Oy`	parses last 2 digits of year using the alternative numeric system, e.g. 十一 is parsed as 11 in ja_JP locale	`tm_year`
`Ey`	parses year as offset from locale's alternative calendar period `%EC`	`tm_year`
`C`	parses the first 2 digits of year as a decimal number (range `[00,99]`)	`tm_year`
`EC`	parses the name of the base year (period) in the locale's alternative representation, e.g. 平成 (Heisei era) in ja_JP	`tm_year`
Month
`b`	parses the month name, either full or abbreviated, e.g. `Oct`	`tm_mon`
`h`	synonym of `b`	`tm_mon`
`B`	synonym of `b`	`tm_mon`
`m`	parses the month as a decimal number (range `[01,12]`), leading zeroes permitted but not required	`tm_mon`
`Om`	parses the month using the alternative numeric system, e.g. 十二 parses as 12 in ja_JP locale	`tm_mon`
Week
`U`	parses the week of the year as a decimal number (Sunday is the first day of the week) (range `[00,53]`), leading zeroes permitted but not required	`tm_year`, `tm_wday`, `tm_yday`
`OU`	parses the week of the year, as by `%U`, using the alternative numeric system, e.g. 五十二 parses as 52 in ja_JP locale	`tm_year`, `tm_wday`, `tm_yday`
`W`	parses the week of the year as a decimal number (Monday is the first day of the week) (range `[00,53]`), leading zeroes permitted but not required	`tm_year`, `tm_wday`, `tm_yday`
`OW`	parses the week of the year, as by `%W`, using the alternative numeric system, e.g. 五十二 parses as 52 in ja_JP locale	`tm_year`, `tm_wday`, `tm_yday`
Day of the year/month
`j`	parses day of the year as a decimal number (range `[001,366]`), leading zeroes permitted but not required	`tm_yday`
`d`	parses the day of the month as a decimal number (range `[01,31]`), leading zeroes permitted but not required	`tm_mday`
`Od`	parses the day of the month using the alternative numeric system, e.g 二十七 parses as 27 in ja_JP locale, leading zeroes permitted but not required	`tm_mday`
`e`	synonym of `d`	`tm_mday`
`Oe`	synonym of `Od`	`tm_mday`
Day of the week
`a`	parses the name of the day of the week, either full or abbreviated, e.g. `Fri`	`tm_wday`
`A`	synonym of `a`	`tm_wday`
`w`	parses weekday as a decimal number, where Sunday is `0` (range `[0-6]`)	`tm_wday`
`Ow`	parses weekday as a decimal number, where Sunday is `0`, using the alternative numeric system, e.g. 二 parses as 2 in ja_JP locale	`tm_wday`
Hour, minute, second
`H`	parses the hour as a decimal number, 24 hour clock (range `[00-23]`), leading zeroes permitted but not required	`tm_hour`
`OH`	parses hour from 24-hour clock using the alternative numeric system, e.g. 十八 parses as 18 in ja_JP locale	`tm_hour`
`I`	parses hour as a decimal number, 12 hour clock (range `[01,12]`), leading zeroes permitted but not required	`tm_hour`
`OI`	parses hour from 12-hour clock using the alternative numeric system, e.g. 六 reads as 06 in ja_JP locale	`tm_hour`
`M`	parses minute as a decimal number (range `[00,59]`), leading zeroes permitted but not required	`tm_min`
`OM`	parses minute using the alternative numeric system, e.g. 二十五 parses as 25 in ja_JP locale	`tm_min`
`S`	parses second as a decimal number (range `[00,60]`), leading zeroes permitted but not required	`tm_sec`
`OS`	parses second using the alternative numeric system, e.g. 二十四 parses as 24 in ja_JP locale	`tm_sec`
Other
`c`	parses the locale's standard date and time string format, e.g. `Sun Oct 17 04:41:13 2010` (locale dependent)	all
`Ec`	parses the locale's alternative date and time string format, e.g. expecting 平成23年 (year Heisei 23) instead of 2011年 (year 2011) in ja_JP locale	all
`x`	parses the locale's standard date representation	all
`Ex`	parses the locale's alternative date representation, e.g. expecting 平成23年 (year Heisei 23) instead of 2011年 (year 2011) in ja_JP locale	all
`X`	parses the locale's standard time representation	all
`EX`	parses the locale's alternative time representation	all
`D`	equivalent to "%m / %d / %y "	`tm_mon`, `tm_mday`, `tm_year`
`r`	parses locale's standard 12-hour clock time (in POSIX, "%I : %M : %S %p")	`tm_hour`, `tm_min`, `tm_sec`
`R`	equivalent to "%H : %M"	`tm_hour`, `tm_min`
`T`	equivalent to "%H : %M : %S"	`tm_hour`, `tm_min`, `tm_sec`
`p`	parses the locale's equivalent of a.m. or p.m.	`tm_hour`

Note: tm_isdst is not written to, and needs to be set explicitly for use with functions such as mktime.

Return value

Returns an object of unspecified type such that if in is the name of an input stream of type std::basic_istream<CharT, Traits>, then the expression in >> get_time(tmb, fmt) behaves as if the following code was executed:

typedef std::istreambuf_iterator<CharT, Traits> Iter; typedef std::time_get<CharT, Iter> TimeGet; std::ios_base::iostate err = std::ios_base::goodbit; const TimeGet& tg = std::use_facet<TimeGet>(in.getloc()); tg.get(Iter(in.rdbuf()), Iter(), in, err, tmb, fmt, fmt + traits::length(fmt)); if (err != std::ios_base::goodbit) in.setstate(err);

Notes

As specified in std::time_get::do_get, which this function calls, it's unspecified if this function zero out the fields in *tmb that are not set directly by the conversion specifiers that appear in fmt: portable programs should initialize every field of *tmb to zero before calling std::get_time.

Example

note: choose clang to observe the output. libstdc++ does not correctly implement the %b specifier: bug 78714.

#include <iostream>
#include <sstream>
#include <locale>
#include <iomanip>
 
int main()
{
    std::tm t = {};
    std::istringstream ss("2011-Februar-18 23:12:34");
    ss.imbue(std::locale("de_DE.utf-8"));
    ss >> std::get_time(&t, "%Y-%b-%d %H:%M:%S");
    if (ss.fail()) {
        std::cout << "Parse failed\n";
    } else {
        std::cout << std::put_time(&t, "%c") << '\n';
    }
}

Possible output:

Sun Feb 18 23:12:34 2011

time_get	parses time/date values from an input character sequence into `struct std::tm` (class template)
put_time (C++11)	formats and outputs a date/time value according to the specified format (function template)

std::get_time

Parameters

Return value

Notes

Example

See also