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std::filesystem::path::generic_string, std::filesystem::path::generic_wstring, std::filesystem::path::generic_u8string, std::filesystem::path::generic_u16string, std::filesystem::path::generic_u32string

From cppreference.com
< cpp‎ | filesystem‎ | path
 
 
 
 
template< class CharT, class Traits = std::char_traits<CharT>,

          class Alloc = std::allocator<CharT> >
std::basic_string<CharT,Traits,Alloc>

    generic_string( const Alloc& a = Alloc() ) const;
(1) (since C++17)
(2) (since C++17)
std::string generic_string() const;
std::wstring generic_wstring() const;
std::u16string generic_u16string() const;
std::u32string generic_u32string() const;
(3)
std::string generic_u8string() const;
(since C++17)
(until C++20)
std::u8string generic_u8string() const;
(since C++20)

Returns the internal pathname in generic pathname format, converted to specific string type. Conversion, if any, is specified as follows:

  • If path::value_type is char, conversion, if any, is system-dependent. This is the case on typical POSIX systems (such as Linux), where native encoding is UTF-8 and string() performs no conversion.
  • Otherwise, if path::value_type is wchar_t, conversion, if any, is unspecified. This is the case on Windows, where wchar_t is 16 bit and the native encoding is UTF-16.
  • Otherwise, if path::value_type is char16_t, native encoding is UTF-16 and the conversion method is unspecified.
  • Otherwise, if path::value_type is char32_t, native encoding is UTF-32 and the conversion method is unspecified.
  • Otherwise, if path::value_type is char8_t, native encoding is UTF-8 and the conversion method is unspecified.

The / character is used as the directory separator.

1) All memory allocations are performed by a.
3) The result encoding in the case of u8string() is always UTF-8.

Contents

[edit] Parameters

a - allocator to construct the string with
Type requirements
-
CharT must be one of the encoded character types (char, wchar_t, char8_t (since C++20), char16_t and char32_t)

[edit] Return value

The internal pathname in generic pathname format, converted to specified string type.

[edit] Exceptions

May throw implementation-defined exceptions.

[edit] Example

#include <cstddef>
#include <filesystem>
#include <iomanip>
#include <iostream>
#include <span>
#include <string_view>
 
void print(std::string_view rem, auto const& str) {
    std::cout << rem << std::hex << std::uppercase << std::setfill('0');
    for (const auto b : std::as_bytes(std::span{str})) {
        std::cout << std::setw(2) << std::to_integer<unsigned>(b) << ' ';
    }
    std::cout << '\n';
}
 
int main()
{
    std::filesystem::path p{"/家/屋"};
    std::cout << p << '\n';
 
    print("string    : ", p.generic_string   ());
    print("u8string  : ", p.generic_u8string ());
    print("u16string : ", p.generic_u16string());
    print("u32string : ", p.generic_u32string());
//  print("wstring   : ", p.generic_wstring  ());
//  gcc-11.0.0 2020.12.30 still fails, clang-10 - ok
}

Possible output:

"/家/屋"
string    : 2F E5 AE B6 2F E5 B1 8B 
u8string  : 2F E5 AE B6 2F E5 B1 8B 
u16string : 2F 00 B6 5B 2F 00 4B 5C 
u32string : 2F 00 00 00 B6 5B 00 00 2F 00 00 00 4B 5C 00 00

[edit] See also

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