Writes a wide character to a file
#include <wchar.h> wint_t fputwc ( wchar_t wc , FILE *fp );
The fputwc( ) function writes a wide character to the current file position of the specified FILE pointer. The return value is the character written, or WEOF if an error occurred. Because the external file associated with a wide-oriented stream is considered to be a sequence of multibyte characters, fputwc( ) implicitly performs a wide-to-multibyte character conversion. If an encoding error occurs in the process, fputwc( ) sets the errno variable to the value of EILSEQ ("illegal byte sequence").
See the example for fgetwc( ) in this chapter.