Question 11.24:Why can't I perform arithmetic on a void * pointer?

那个谁

Q: Why can't I perform arithmetic on a void * pointer? A: The compiler doesn't know the size of the pointed-to objects. (Remember that pointer arithmetic is always in terms of the pointed-to size; see also question 4.4.) Therefore, arithmetic on void *'s is disallowed (though some compilers allow it as an extension). Before performing arithmetic, convert the pointer either to char * or to the pointer type you're trying to manipulate (but see also questions 4.5 and 16.7).     

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问题：为什么我不能对void *类型的指针进行算术操作？
回答：编译器不知道所指向的对象的大小（要记住指针运算总是要依赖所指向的对象的大小的；参考问题4.4）。因此基于void *类型的指针的运算是不被允许的（尽管一些编译器作为扩展是允许的）。在操作运算之前，要将指针要么转换为char *类型的或者你想要操作的指针的类型（也可以参考问题4.5和16.7）。