@param s kstring to write into @param n number of items in @p data @param type type of items in @p data @param data BCF format data @return 0 on success -1 if out of memory
See Implementation
@param s kstring to write into @param n number of items in @p data @param type type of items in @p data @param data BCF format data @return 0 on success -1 if out of memory