std::filesystem::path::c_str, std::filesystem::path::native, std::filesystem::path::operator string_type() - cppreference.com

##### cppreference.com

##### Search

Create account

##### Namespaces

- Page
- Discussion

##### Variants

##### Views

- View
- Edit
- History

##### Actions

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

From cppreference.com
< cpp‎ | filesystem‎ | path

const value_type* c_str() const; | (1) | (since C++17)
const string_type& native() const; | (2) | (since C++17)
operator string_type() const; | (3) | (since C++17)

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.

### [edit] Parameters

(none)

### [edit] 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.

### [edit] Exceptions

1,2)
`noexcept` specification:
noexcept

### [edit] 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:

    std::filesystem::path p = "/tmp/text.txt";
    std::ifstream f(p);

### [edit] Example

Run this code

    #include <cstdio>
    #ifdef _MSC_VER
    #include <io.h>
    #include <fcntl.h>
    #else
    #include <locale>
    #include <clocale>
    #endif
    #include <fstream>
    #include <iostream>
    #include <filesystem>
    namespace fs = std::filesystem;

    int main()
    {
    #ifdef _MSC_VER
        _setmode(_fileno(stderr), _O_WTEXT);
    #else
        std::setlocale(LC_ALL, "");
        std::locale::global(std::locale(""));
        std::cout.imbue(std::locale());
        std::wcerr.imbue(std::locale());
    #endif

        fs::path p = fs::u8path(u8"要らない.txt");
        std::ofstream(p) << "File contents"; // Prior to LWG2676 uses operator string_type()
                                             // on MSVC, where string_type is wstring, only
                                             // works due to non-standard extension.
                                             // Post-LWG2676 uses new fstream constructors

        // native string representation can be used with OS APIs
        if (std::FILE* f =
    #ifdef _MSC_VER
                    _wfopen(p.c_str(), L"r")
    #else
                    std::fopen(p.c_str(), "r")
    #endif
            )
        {
            int ch;
            while((ch=fgetc(f))!= EOF) putchar(ch);
            std::fclose(f);
        }

        // multibyte and wide representation can be used for output
        std::cout << "\nFile name in narrow multibyte encoding: " << p.string() << '\n';
        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

### [edit] See also

stringwstringu8stringu16stringu32string | returns the path in native pathname format converted to a string (public member function) [edit]
generic_stringgeneric_wstringgeneric_u8stringgeneric_u16stringgeneric_u32string | returns the path in generic pathname format converted to a string (public member function) [edit]

Retrieved from "http://en.cppreference.com/mwiki/index.php?title=cpp/filesystem/path/native&oldid=91320"
Category:

- unconditionally noexcept

Hidden categories:

- Pages with unreviewed unconditional noexcept template
- Pages with unreviewed noexcept template