scalbn和ldexp之间有什么区别

Question

and scalbn(double a, int exp) as C99标准将ldexp(double a, int exp)定义和scalbn(double a, int exp)为

如果我使用IEEE-754算法（即FLT_RADIX == 2），两者之间有什么区别？

Answer 1

附录F：

F.9.3.6  The ldexp functions

       [#1] On a binary system, ldexp(x, exp) is equivalent to

               scalbn(x, exp)

Answer 2

FLT_RADIX == 2时没有区别。