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
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.
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.
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.