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std::fgetws(3)		       C++ Standard Libary		  std::fgetws(3)

NAME
     std::fgetws - std::fgetws

Synopsis
	Defined in header <cwchar>
	wchar_t* fgetws( wchar_t* str, int count, std::FILE* stream );

	Reads  at  most count - 1 wide characters from the given file stream and
     stores them
	in str. The produced wide  string  is  always  null-terminated.  Parsing
     stops if
	end-of-file  occurs  or a newline wide character is found, in which case
     str will
	contain that wide newline character.

Parameters
	str    - wide string to read the characters to
	count  - the length of str
	stream - file stream to read the data from

Return value
	str on success, a null pointer on an error.

Example
     // Run this code

      #include <array>
      #include <clocale>
      #include <cstdio>
      #include <cstdlib>
      #include <cwchar>
      #include <cwctype>
      #include <iomanip>
      #include <iostream>
      #include <span>
      #include <string>

      void dump(std::span<const wchar_t> sp, std::size_t width = 14)
      {
	  for (wchar_t wc : sp)
	      std::wcout << (std::iswprint(wc) ? wc : L'.');
	  std::wcout << std::wstring(width > sp.size() ? width - sp.size() :  1,
     L' ')
		     << std::hex << std::uppercase << std::setfill(L'0');
	  for (wchar_t wc : sp)
	      std::wcout << std::setw(sizeof wc) << static_cast<unsigned>(wc) <<
     ' ';
	  std::wcout << '\n';
      }

      int main()
      {
	  // Create temp file that contains wide characters
	  std::setlocale(LC_ALL, "en_US.utf8");
	  std::FILE* tmpf = std::tmpfile();

	  for (const wchar_t* text : {
	      L"TA(C)traA"dre"	  L"\n",
	      L"Cube"	      L"\n",
	      L"OctaA"dre"     L"\n",
	      L"IcosaA"dre"    L"\n",
	      L"DodA(C)caA"dre"   L"\n"
	      })
	      if (int rc = std::fputws(text, tmpf); rc == EOF)
	      {
		  std::perror("fputws()"); // POSIX requires that errno is set
		  return EXIT_FAILURE;
	      }

	  std::rewind(tmpf);

	  std::array<wchar_t, 12> buf;
	  while (std::fgetws(buf.data(), buf.size(), tmpf) != nullptr)
	      dump(std::span(buf.data(), buf.size()));

	  return EXIT_SUCCESS;
      }

Possible output:
      TA(C)traA"dre...	 0054  00E9 0074 0072 0061 00E8 0064 0072 0065 000A 0000
     0000
      Cube..dre...  0043 0075 0062 0065 000A 0000 0064 0072 0065 000A 0000 0000
      OctaA"dre....  004F 0063 0074 0061 00E8 0064 0072 0065 000A 0000 0000 0000
      IcosaA"dre...  0049 0063 006F 0073 0061 00E8 0064 0072 0065 000A 0000 0000
      DodA(C)caA"dre..	0044 006F 0064 00E9 0063 0061 00E8 0064 0072  0065  000A
     0000

See also
	wscanf	 reads	formatted wide character input from stdin, a file stream
     or a buffer
	fwscanf (function)
	swscanf
	fgetwc	gets a wide character from a file stream
	getwc	(function)
	fputws	writes a wide string to a file stream
		(function)
	C documentation for
	fgetws

http://cppreference.com 	   2024.06.10			  std::fgetws(3)
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