UCNICONVOPN

Message        The call iconv_open(<CODESET>, "UCS-4") failed
               because:  <STRERROR>.  UCNs will not be mapped to the
               native character set.

Description    To translate Universal Character Name escape
               sequences to the codeset of the current locale, the
               compiler needs to call the iconv_open library routine
               with the specified parameters.  This call failed, for
               the reason shown.  Thus no UCN escape sequences in
               this program can be translated.

User Action    Make sure your system has the specified codeset
               converter installed, or set your locale to use a
               codeset for which a converter from UCS-4 is
               available.  Alternatively, change your code to avoid
               the use of UCNs, e.g.  using hexadecimal escape
               sequences.