Using C Unions on a Raspberry Pi

Whilst revisiting the use of ‘C’ I remembered about ‘unions’ and how they can be used to view data in memory in different ways.

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And here is the code:

#include <stdio.h>

union {
    unsigned int i;
    unsigned char c;
} aunion;

int main() {
    aunion.i = 42;

    printf("The answers are %d and %c\nWhy is that?\n", aunion.i, aunion.c);
    printf("Unions are a facinating way of manipulating memory content\n");
    printf("But can be dangerous, which is why you will not find them in Java\n");
    printf("What is happening with the union 'aunion'?\n\n");

    printf("And like the last video, this is fast to compile\n");
    printf("But with Java you can take the .class file and run it on anything\n");
    printf("with a a Java Virtual Machine.\n");

    return aunion.i;