[time.zone.info.local]

# 30 Time library [[time]](./#time)

## 30.11 Time zones [[time.zone]](time.zone#info.local)

### 30.11.4 Information classes [[time.zone.info]](time.zone.info#local)

#### 30.11.4.2 Class local_info [time.zone.info.local]

[ð](#lib:unique,local_info)

namespace std::chrono {struct local_info {static constexpr int unique = 0; static constexpr int nonexistent = 1; static constexpr int ambiguous = 2; int result;
 sys_info first;
 sys_info second; };}

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L9337)

[*Note [1](#note-1)*:

This type provides a low-level interface to time zone information[.](#1.sentence-1)

Typical conversions from local_time to sys_time will use this class implicitly, not explicitly[.](#1.sentence-2)

â *end note*]

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L9344)

Describes the result of converting a local_time to a sys_time as follows:

- [(2.1)](#2.1)

  When a local_time to sys_time conversion is unique,result == unique,first will be filled out with the correct sys_info,
andsecond will be zero-initialized[.](#2.1.sentence-1)

- [(2.2)](#2.2)

  If the conversion stems from a nonexistent local_time then result == nonexistent,first will be filled out with the sys_info that ends just prior to the local_time,
andsecond will be filled out with the sys_info that begins just after the local_time[.](#2.2.sentence-1)

- [(2.3)](#2.3)

  If the conversion stems from an ambiguous local_time,
then result == ambiguous,first will be filled out with the sys_info that ends just after the local_time,
andsecond will be filled out with the sys_info that starts just before the local_time[.](#2.3.sentence-1)

[ð](#lib:operator%3c%3c,local_info)

`template<class charT, class traits>
  basic_ostream<charT, traits>&
    operator<<(basic_ostream<charT, traits>& os, const local_info& r);
`

[3](#3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L9382)

*Effects*: Streams out the local_info object r in an unspecified format[.](#3.sentence-1)

[4](#4)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/time.tex#L9386)

*Returns*: os[.](#4.sentence-1)
