Here are the data structures with brief descriptions:

converter_state_t	Structure holding the pointers to the data and the state of a state table converter
save_state_t	Structure holding the shift state of a state table converter
transcript_iconv_t	An opaque handle representing the transcript_iconv state
transcript_name_t	A structure holding a display name and availability information about a converter
transcript_t	An opaque structure describing a converter and its state