std::experimental::filesystem::path::c_str, std::experimental::filesystem::path::native, std::experimental::filesystem::path::operator string_type()

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Technical specifications
Filesystem library (filesystem TS)
Library fundamentals (library fundamentals TS)
Library fundamentals 2 (library fundamentals 2 TS)
Extensions for parallelism (parallelism TS)
Extensions for parallelism 2 (parallelism TS v2)
Extensions for concurrency (concurrency TS)
Concepts (concepts TS)
Ranges (ranges TS)
Special mathematical functions (special math TR)
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

#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".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: .txt
File name in wide encoding: .txt

See also

returns the path in native pathname format converted to a string
(public member function)
returns the path in generic pathname format converted to a string
(public member function)