function is the wide-character equivalent
It reads a wide character from stream and returns it.
If the end of stream is reached, or if ferror(stream) becomes true,
If a wide-character conversion error occurs, it sets
errno to EILSEQ and returns
function or macro functions identically to
It may be implemented as a macro, and may evaluate its argument
more than once.
There is no reason ever to use it.
function returns the next wide-character
from the stream, or
Apart from the usual ones, there is
The data obtained from the input stream does not
form a valid character.
The behavior of
depends on the
category of the
In the absence of additional information passed to the
call, it is
reasonable to expect that
will actually read a multibyte sequence
from the stream and then convert it to a wide character.