[C] sizeof single struct member and relative length of struct
#define member_size(type, member) sizeof(((type *)0)->member) (reference: https://stackoverflow.com/questions/3553296/c-sizeof-single-struct-member) // member_length #define member_length(type, member) ((((type *)0)->member)+member_size(type, member)) If you use padding, it's is possible that member_length has some errors.