RkInitialize initiates the kana-kanji conversion functions. dhdpath names the dictionary home directory.
Because this library permits multiple kana-kanji conversions to proceed concurrently, it uses the
conversion context method of control to manage the kana-kanji conversions. Each context contains
internal data needed to perform a kana-kanji conversion.
Users identify the conversion contexts from one another by their context number. A context number is an
integer of 0 or greater and is used as the first parameter of the kana-kanji conversion function.
Right after the kana-kanji conversion functions are initialized by RkInitialize, only the standard
context with context number 0 exists. Applications using only one context can use the standard context.