29 Time library [time]

29.5 Class template duration [time.duration]

29.5.11 I/O [time.duration.io]

template<class charT, class traits, class Rep, class Period> basic_ostream<charT, traits>& operator<<(basic_ostream<charT, traits>& os, const duration<Rep, Period>& d);
Effects: Inserts the duration d onto the stream os as if it were implemented as follows: basic_ostringstream<charT, traits> s; s.flags(os.flags()); s.imbue(os.getloc()); s.precision(os.precision()); s << d.count() << units-suffix; return os << s.str(); where units-suffix depends on the type Period​::​type as follows:
  • If Period​::​type is atto, units-suffix is "as".
  • Otherwise, if Period​::​type is femto, units-suffix is "fs".
  • Otherwise, if Period​::​type is pico, units-suffix is "ps".
  • Otherwise, if Period​::​type is nano, units-suffix is "ns".
  • Otherwise, if Period​::​type is micro, it is implementation-defined whether units-suffix is "Ξs" ("\u00b5\u0073") or "us".
  • Otherwise, if Period​::​type is milli, units-suffix is "ms".
  • Otherwise, if Period​::​type is centi, units-suffix is "cs".
  • Otherwise, if Period​::​type is deci, units-suffix is "ds".
  • Otherwise, if Period​::​type is ratio<1>, units-suffix is "s".
  • Otherwise, if Period​::​type is deca, units-suffix is "das".
  • Otherwise, if Period​::​type is hecto, units-suffix is "hs".
  • Otherwise, if Period​::​type is kilo, units-suffix is "ks".
  • Otherwise, if Period​::​type is mega, units-suffix is "Ms".
  • Otherwise, if Period​::​type is giga, units-suffix is "Gs".
  • Otherwise, if Period​::​type is tera, units-suffix is "Ts".
  • Otherwise, if Period​::​type is peta, units-suffix is "Ps".
  • Otherwise, if Period​::​type is exa, units-suffix is "Es".
  • Otherwise, if Period​::​type is ratio<60>, units-suffix is "min".
  • Otherwise, if Period​::​type is ratio<3600>, units-suffix is "h".
  • Otherwise, if Period​::​type is ratio<86400>, units-suffix is "d".
  • Otherwise, if Period​::​type​::​den == 1, units-suffix is "[num]s".
  • Otherwise, units-suffix is "[num/den]s".
In the list above, the use of num and den refers to the static data members of Period​::​type, which are converted to arrays of charT using a decimal conversion with no leading zeroes.
Returns: os.
template<class charT, class traits, class Rep, class Period, class Alloc = allocator<charT>> basic_istream<charT, traits>& from_stream(basic_istream<charT, traits>& is, const charT* fmt, duration<Rep, Period>& d, basic_string<charT, traits, Alloc>* abbrev = nullptr, minutes* offset = nullptr);
Effects: Attempts to parse the input stream is into the duration d using the format flags given in the NTCTS fmt as specified in [time.parse].
If the parse fails to decode a valid duration, is.setstate(ios_base​::​failbit) is called and d is not modified.
If %Z is used and successfully parsed, that value will be assigned to *abbrev if abbrev is non-null.
If %z (or a modified variant) is used and successfully parsed, that value will be assigned to *offset if offset is non-null.
Returns: is.