str_offset       1495 string.c       	len = str_offset(p, e, len, enc, 0);
str_offset       2301 string.c       	offset = str_offset(s, RSTRING_END(str), offset, enc, single_byte_optimizable(str));
str_offset       2365 string.c       	pos = str_offset(RSTRING_PTR(str), RSTRING_END(str), pos,
str_offset       2479 string.c       	pos = str_offset(RSTRING_PTR(str), RSTRING_END(str), pos,