x                  The number of successfully matched and
                       assigned input items.
    EOF                Indicates that the end-of-file was encountered
                       or a read error occurred. If a read error
                       occurs, the function sets errno to one of the
                       following:

                       o  EILSEQ - Invalid character detected.

                       o  EVMSERR - Nontranslatable OpenVMS error.
                          vaxc$errno contains the OpenVMS error code.
                          This can indicate that conversion to a
                          numeric value failed due to overflow.

                       The function can also set errno to the
                       following as a result of errors returned from
                       the I/O subsystem:

                       o  EBADF - The file descriptor is not valid.

                       o  EIO - I/O error.

                       o  ENXIO - Device does not exist.

                       o  EPIPE - Broken pipe.

                       o  EVMSERR - Nontranslatable OpenVMS error.
                          vaxc$errno contains the OpenVMS error code.
                          This indicates that an I/O error occurred
                          for which there is no equivalent C error
                          code.