How do I use unions in C programming?

How do I use unions in C programming?

Unions in C allow you to store different data types in the same memory location. You define a union using the union keyword.

Can you give me an example of how to define and use a union?

Sure! Here's a simple example:

union Data {
    int intValue;
    float floatValue;
    char charValue;
};

union Data data;

data.intValue = 5;
printf("Integer: %d\n", data.intValue);

data.floatValue = 3.14;
printf("Float: %f\n", data.floatValue);

This shows how to define a union and access its members.

What happens if I store a value in one member and then access another?

Accessing a different member after storing a value in one will give you unpredictable results, as all members share the same memory. Always access the member that was last written to.

Are there any limitations or best practices when using unions?

Yes, be cautious about type safety and always ensure you know which member is currently valid. It's also good practice to use a struct with a type identifier to keep track of the active member.