Determines if a wide character corresponds to a single-
    byte multibyte character and returns its multibyte character
    representation.

    Format

      #include  <stdio.h>

      #include  <wchar.h>

      int wctob  (wint_t c);

1 - Argument

 c

    The wide character to be converted to a single-byte multibyte
    character.

2 - Description

    The wctob function determines whether the specified wide
    character corresponds to a single-byte multibyte character when
    in the initial shift state and, if so, returns its multibyte
    character representation.

3 - Return Values

    x                  The single-byte representation of the wide
                       character specified.
    EOF                Indicates an error. The wide character
                       specified does not correspond to a single-byte
                       multibyte character.