http://www.ktug.org/xe/index.php?document_srl=190359

http://www.ktug.org/xe/index.php?document_srl=244838#comment_244845

http://www.ktug.org/xe/index.php?document_srl=227488#comment_227510

komkindex.pl

  "Usage: $progname [-euc] [makeindex options] idx_filename[s]\n",
  "       -euc: exec hmakeindex, passing other arguments as they are.\n\n",
  "       $progname [-k] [makeindex options] idx_filename[s]\n",
  "       -k: put hangul index entries before than others.\n\n";

https://ctan.org/tex-archive/language/korean/kotex-utils?lang=en