getws reads EUC characters from stdin,
converts them to wchar_t characters, and places them in
the wchar_t array pointed to by s.
getws reads until a newline character is read or an end-of-file
condition is encountered.
The newline character is discarded and the wchar_t string is
terminated with a wchar_t null character.
Errors
If end-of-file or a read error is encountered and no characters have been
transformed, no wchar_t characters are transferred to s
and a null pointer is returned and the error indicator for the stream is set.
If the read error is an illegal byte sequence,
errno is set to EILSEQ.
If end-of-file is encountered, the EOF indicator for the stream is set.
Otherwise, s is returned.