anonymous structures/unions in C with example

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What are anonymous structures/unions?

 Structures/unions with no names are called anonymous structures/unions. They are also called unnamed unions/structures.

As there are no names, we cannot create variables of anonymous structures/unions, but we can use them in nested structures or unions.

Real World Example of anonymous structures/unions:

 A status register of a microcontroller can have multiple bits. Sometimes we read the value of each bit, and sometimes the whole register. We can use anonymous structure/unions in this to easily refer to both.

Code:



Output:

 $ ./anonymous

Status register value:0x83

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