Std::experimental::filesystem::path::c_str,std::experimental::filesystem::path::native, (3) Linux Manual Page

std::experimental::filesystem::path::c_str,std::experimental::filesystem::path::native, – std::experimental::filesystem::path::c_str,std::experimental::filesystem::path::native,

Synopsis

const value_type *c_str() const;
(1)(filesystem TS)

    const string_type &native() const;
(2)(filesystem TS)

operator string_type() const;
(3)(filesystem TS)

Accesses the native path name as a character string.
1) Equivalent to native().c_str().
2) Returns the native string representation of the pathname by reference.
3) Returns the native string representation of the pathname by value.

Parameters

(none)

Return value

The native string representation of the pathname, using native syntax, native
character type, and native character encoding. This string is suitable for use with
OS APIs.

Exceptions

1,2)
noexcept specification:
noexcept

Notes

The conversion function (3) is provided so that standard file-opening APIs that
accept std::basic_string file names, such as the std::ifstream constructor, can use
pathnames with no changes to code:

fs::path p = "/tmp/text.txt";

std::ifstream f(p);

Example

// Run this code

#include <cstdio>

#include <clocale>

#include <fstream>

#include <iostream>

#include <experimental/filesystem>

namespace fs = std::experimental::filesystem;
int main()

{
    std::setlocale(LC_ALL, "en_US.utf8");
    std::locale::global(std::locale("en_US.utf8"));
    fs::path p = fs::u8path(u8"要らない.txt");
    // native string representation can be used with OS APIs
    std::ofstream(p) << "File contents"; // this uses operator string()
    if (std::FILE *f = std::fopen(p.c_str(), "r")) {

        int ch;

        while ((ch = fgetc(f)) != EOF)
            putchar(ch);

        std::fclose(f);
    }
    // multibyte and wide representation can be used for output
    std::cout.imbue(std::locale());
    std::cout << "\nFile name in narrow multibyte encoding: "
              << p.string() << '\n';
    std::wcerr.imbue(std::locale());
    std::wcerr << "File name in wide encoding: "
               << p.wstring() << '\n';
    fs::remove(p);
}

Output:

File contents
File name in narrow multibyte encoding: 要らない.txt
File name in wide encoding: 要らない.txt

std::experimental::filesystem::path::c_str,std::experimental::filesystem::path::native, (3) Linux Manual Page