c/io/fgetwc

Reads the next wide character from the given input stream. may be implemented as a macro and may evaluate more than once.

Return value
The next wide character from the stream or on failure.

If the failure has been caused by end-of-file condition, additionally sets the eof indicator (see feof) on. If the failure has been caused by some other error, sets the error indicator (see ferror) on.

If an encoding error occurred, additionally sets errno to.