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 doesn't make sense to get bit's address within a byte...?(cause this types pointer arithmetic will be awkward ?)
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What value would you expect the "address of a bit" to have?? – Kerrek SB Nov 24 '11 at 14:22
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You can modify bits by requesting the char it is in, and then use bitmasking operations. – Yuri Nov 24 '11 at 14:24
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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.
David Heffernan
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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.
Oliver Charlesworth
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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.
Vicky
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