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

 

C++

Language

Standard library headers

Concepts

Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Filesystem library

Classes
filesystem::path filesystem::filesystem_error filesystem::directory_entry filesystem::directory_iterator filesystem::recursive_directory_iterator filesystem::file_status	filesystem::space_info filesystem::file_type filesystem::perms filesystem::copy_options filesystem::directory_options filesystem::file_time_type
Functions
filesystem::absolute filesystem::system_complete filesystem::canonical filesystem::copy filesystem::copy_file filesystem::copy_symlink filesystem::create_directory filesystem::create_directories filesystem::create_hard_link filesystem::create_symlink filesystem::create_directory_symlink filesystem::current_path filesystem::exists filesystem::equivalent	filesystem::file_size filesystem::hard_link_count filesystem::last_write_time filesystem::permissions filesystem::read_symlink filesystem::remove filesystem::remove_all filesystem::rename filesystem::resize_file filesystem::space filesystem::status filesystem::symlink_status filesystem::temp_directory_path
File types
filesystem::is_block_file filesystem::is_character_file filesystem::is_directory filesystem::is_empty filesystem::status_known	filesystem::is_fifo filesystem::is_other filesystem::is_regular_file filesystem::is_socket filesystem::is_symlink

 

std::filesystem::path

Member functions
path::path path::~path path::operator= path::assign path::append path::concatpath::operator += path::clear path::make_preferred path::remove_filename path::replace_filename path::replace_extension path::swap path::compare	path::c_strpath::nativepath::operator string_type path::stringpath::u8stringpath::u16stringpath::u32stringpath::wstring path::generic_stringpath::generic_u8stringpath::generic_u16stringpath::generic_u32stringpath::generic_wstring path::beginpath::end
Path decomposition
path::root_name path::root_directory path::root_path path::relative_path path::parent_path path::filename path::stem path::extension path::empty	path::has_root_pathpath::has_root_namepath::has_root_directorypath::has_relative_pathpath::has_parent_pathpath::has_filenamepath::has_stempath::has_extension path::is_absolutepath::is_relative
Non-member functions
swap(path)
hash_value
operator==operator!=operator<operator<=operator>operator>=
operator/
operator<<operator>>
u8path

 

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.

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:

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

Example

Run this code

#include <cstdio>
#include <clocale>
#include <fstream>
#include <iostream>
#include <filesystem>
namespace fs = std::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

See also

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