27 Input/output library [input.output]

27.10 File systems [filesystems]

27.10.8 Class path [class.path]

27.10.8.4 path members [path.member]

27.10.8.4.1 path constructors [path.construct]

path() noexcept;

1

Effects: Constructs an object of class path.

2

Postconditions: empty() == true.

path(const path& p); path(path&& p) noexcept;

3

Effects: Constructs an object of class path with pathstring having the original value of p.pathstring. In the second form, p is left in a valid but unspecified state.

path(string_type&& source);

4

Effects: Constructs an object of class path with pathstring having the original value of source. source is left in a valid but unspecified state.

template <class Source> path(const Source& source); template <class InputIterator> path(InputIterator first, InputIterator last);

5

Effects: Constructs an object of class path, storing the effective range of source ([path.req]) or the range [first, last) in pathstring, converting format and encoding if required ([path.cvt]).

template <class Source> path(const Source& source, const locale& loc); template <class InputIterator> path(InputIterator first, InputIterator last, const locale& loc);

6

Requires: The value type of Source and InputIterator is char.

7

Effects: Constructs an object of class path, storing the effective range of source or the range [first, last) in pathstring, after converting format if required and after converting the encoding as follows:

  • (7.1)

    If value_type is wchar_t, converts to the native wide encoding ([fs.def.native.encode]) using the codecvt<wchar_t, char, mbstate_t> facet of loc.

  • (7.2)

    Otherwise a conversion is performed using the codecvt<wchar_t, char, mbstate_t> facet of loc, and then a second conversion to the current narrow encoding.

[ Example: A string is to be read from a database that is encoded in ISO/IEC 8859-1, and used to create a directory: 

namespace fs = std::filesystem;
std::string latin1_string = read_latin1_data();
codecvt_8859_1<wchar_t> latin1_facet;
std::locale latin1_locale(std::locale(), latin1_facet);
fs::create_directory(fs::path(latin1_string, latin1_locale));

For POSIX-based operating systems, the path is constructed by first using latin1_facet to convert ISO/IEC 8859-1 encoded latin1_string to a wide character string in the native wide encoding ([fs.def.native.encode]). The resulting wide string is then converted to a narrow character pathstring string in the current native narrow encoding. If the native wide encoding is UTF-16 or UTF-32, and the current native narrow encoding is UTF-8, all of the characters in the ISO/IEC 8859-1 character set will be converted to their Unicode representation, but for other native narrow encodings some characters may have no representation.

For Windows-based operating systems, the path is constructed by using latin1_facet to convert ISO/IEC 8859-1 encoded latin1_string to a UTF-16 encoded wide character pathstring string. All of the characters in the ISO/IEC 8859-1 character set will be converted to their Unicode representation.  — end example ]