C Unions and Enums

Share memory locations across datatypes with unions and define named integer constants.

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A union stores different data types in the same memory location. The size of the union is the size of its largest member. An enum defines a type containing named integer constants.

Key Takeaways: C Unions and Enums

Mastering C Unions and Enums helps you write clean and reliable C code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.

C Unions and Enums Code Example

#include <stdio.h>

union Data {
    int i;
    float f;
};

int main() {
    union Data data;
    data.i = 10;
    printf("data.i: %d\n", data.i);
    data.f = 220.5;
    printf("data.f: %.1f\n", data.f);
    return 0;
}

Output

data.i: 10
data.f: 220.5

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C Buffer Overflow Prevention

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C Unions and Enums

💡 Key Takeaways: C Unions and Enums

C Unions and Enums Code Example

Key Takeaways: C Unions and Enums