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std::filesystem::u8path(3)     C++ Standard Libary    std::filesystem::u8path(3)

NAME
     std::filesystem::u8path - std::filesystem::u8path

Synopsis
	Defined in header <filesystem>
	template<  class  Source  >				      (1) (since
     C++17)
	std::filesystem::path u8path( const Source& source  );		 (depre-
     cated in C++20)
	template<  class  InputIt  >					  (since
     C++17)
	std::filesystem::path u8path( InputIt first, InputIt last   (2)  (depre-
     cated in C++20)
	);

	Constructs a path p from a UTF-8 encoded sequence of chars
	or char8_ts
	(since	  C++20),   supplied   either	as   an   std::string,	 or   as
     std::string_view, or as a
	null-terminated multibyte string, or as a [first, last) iterator pair.

	  * If path::value_type is char and native encoding is UTF-8, constructs
     a path
	    directly as if by path(source) or path(first, last). Note:	this  is
     the typical
	    situation of a POSIX system that uses Unicode, such as Linux.
	  *  Otherwise,  if  path::value_type  is wchar_t and native encoding is
     UTF-16 (this is
	    the situation on Windows), or if path::value_type is  char16_t  (na-
     tive encoding
	    guaranteed	UTF-16) or char32_t (native encoding guaranteed UTF-32),
     then first
	    converts the UTF-8 character sequence to a temporary string  tmp  of
     type
	    path::string_type  and  then  the  new  path is constructed as if by
     path(tmp).
	  * Otherwise (for non-UTF-8 narrow character  encodings  and  for  non-
     UTF-16 wchar_t),
	    first   converts   the  UTF-8  character  sequence	to  a  temporary
     UTF-32-encoded string
	    tmp of type std::u32string, and then the new path is constructed  as
     if by
	    path(tmp)  (this  path is taken on a POSIX system with a non-Unicode
     multibyte or
	    single-byte encoded filesystem).

Parameters
		      a UTF-8 encoded std::string, std::string_view,  a  pointer
     to a
	source	     -	null-terminated  multibyte  string, or an input iterator
     with char value
		      type that points to a null-terminated multibyte string
	first, last - pair of LegacyInputIterators that specify a UTF-8  encoded
     character
		      sequence

Type requirements
	-
	InputIt must meet the requirements of LegacyInputIterator.
	-
	The value type of Source or InputIt must be char
	or char8_t.
	(since C++20)

Return value
	The  path  constructed from the input string after conversion from UTF-8
     to the
	filesystem's native character encoding.

Exceptions
	May throw std::bad_alloc if memory allocation fails.

Notes
	On systems where native path format differs from the generic path format
     (neither
	Windows nor POSIX systems are examples of such OSes), if the argument to
     this
	function is using generic format, it will be converted to native.

Example
     // Run this code

      #include <cstdio>
      #ifdef _MSC_VER
      #include <fcntl.h>
      #include <io.h>
      #else
      #include <clocale>
      #include <locale>
      #endif
      #include <filesystem>
      #include <fstream>

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

	  std::filesystem::path p(u8"e|aaaa.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 ex-
     tension.
					       // Post-LWG2676 uses new  fstream
     constructors

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

	  std::filesystem::remove(p);
      }

Possible output:
      File contents

See also
	path	represents a path
	(C++17) (class)

http://cppreference.com 	   2024.06.10	      std::filesystem::u8path(3)
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