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iconv() is now dobne by a version of Yukihiro Nakadaira's win_iconv rather than by libiconv. This version is based on Windows' codepages and is not quite as comprehensive as libiconv: it is however much smaller and easier to maintain. The implementation here is 100% compatible: you can drop in libiconv's iconv.dll as a replacement if you need it, from http://www.stats.ox.ac.uk/pub/Rtools/Riconv.dll. To avoid name conflicts with GTk+, it has been renamed to Riconv.dll.