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

NAME
     std::btowc - std::btowc

Synopsis
	Defined in header <cwchar>
	std::wint_t btowc( int c );

	Widens a single-byte character c to its wide character equivalent.

	Most  multibyte  character  encodings use single-byte codes to represent
     the characters
	from the ASCII character set. This function may be used to convert  such
     characters
	to wchar_t.

Parameters
	c - single-byte character to widen

Return value
	WEOF if c is EOF.

	Wide  character  representation of c if (unsigned char)c is a valid sin-
     gle-byte
	character in the initial shift state, WEOF otherwise.

Example
     // Run this code

      #include <clocale>
      #include <cwchar>
      #include <iostream>

      void try_widen(char c)
      {
	  std::wint_t w = std::btowc(c);
	  if (w != WEOF)
	      std::cout << "The single-byte character " << +(unsigned char)c
			<< " widens to " << +w << '\n';
	  else
	      std::cout << "The single-byte character " << +(unsigned char)c
			<< " failed to widen\n";
      }

      int main()
      {
	  std::setlocale(LC_ALL, "lt_LT.iso88594");
	  std::cout << std::hex << std::showbase <<  "In  Lithuanian  ISO-8859-4
     locale:\n";
	  try_widen('A');
	  try_widen('\xdf'); // German letter A (U+00df) in ISO-8859-4
	  try_widen('\xf9'); // Lithuanian letter A^3 (U+0173) in ISO-8859-4

	  std::setlocale(LC_ALL, "lt_LT.utf8");
	  std::cout << "In Lithuanian UTF-8 locale:\n";
	  try_widen('A');
	  try_widen('\xdf');
	  try_widen('\xf9');
      }

Possible output:
      In Lithuanian ISO-8859-4 locale:
      The single-byte character 0x41 widens to 0x41
      The single-byte character 0xdf widens to 0xdf
      The single-byte character 0xf9 widens to 0x173
      In Lithuanian UTF-8 locale:
      The single-byte character 0x41 widens to 0x41
      The single-byte character 0xdf failed to widen
      The single-byte character 0xf9 failed to widen

See also
	wctob	  narrows a wide character to a single-byte narrow character, if
     possible
		  (function)
	do_widen  converts a character or characters from char to CharT
	[virtual] (virtual protected member function of std::ctype<CharT>)
	C documentation for
	btowc

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