$ nkf -w siro.txt
;;; -*- coding: euc-jp -*-
;; okuri-ari entries.
;; okuri-nasi entries.
しろ /城/
$ echo "q S i r o K u" | skk -u siro.txt
{ "input": "q S i r o K u", "output": "", "preedit": "▼城ク" } # should be "白ク" because...
$ echo "S i r o K u" | skk -u siro.txt
{ "input": "S i r o K u", "output": "", "preedit": "▼白く" }
"qSiroKu" is the same as "qSiro ku"