Accessing bit-field in C by its address

后端 未结 3 748
感动是毒
感动是毒 2021-01-07 00:33

What is the reason behind not allowing to access a bit field in C using its address, is it cause it might not be an address that is not system word aligned ..? or as it does

相关标签:
3条回答
  • 2021-01-07 00:44

    In c smallest addressable unit of memory is considered a Byte. A pointer points to a memory location which can be of any data_type (a pointer is also another variable). Bits receding in byte don't have any address , rather they do have a bit position.

    So basically you can not point to particular bit , you can point to a byte or whole word.

    0 讨论(0)
  • 2021-01-07 01:01

    Bits do not have addresses. That's why you can't refer to them by address. The granularity of addressing is the char.

    I guess the reasoning is that the language was design to match the architecture it targeted, and I know of no machine which allows addressing of individual bits.

    0 讨论(0)
  • 2021-01-07 01:09

    The smallest unit of addressable memory in C is a char, because this corresponds to the smallest unit of addressable memory on most CPU architectures.* It doesn't make sense to talk about the address of a bit.


    * One could imagine a hypothetical machine that allowed addressing of individual bits, but it would be pretty esoteric.

    0 讨论(0)
提交回复
热议问题