Programming

#include <stdio.h>

typedef struct type_float {
        int type;
        float payload;
} type_float;

typedef struct type_string {
        int type;
        char payload[64];
} type_string;

typedef union alltypes {
        /* An enum is like an integer, plus a bunch of #define's.
            TYPE_FLOAT becomes 0, TYPE_STRING becomes 1, etc, etc. */
        enum { TYPE_FLOAT, TYPE_STRING } type;
        type_float t_float;
        type_string t_string;
} alltypes;

int dosomething(alltypes *a)
{
        switch(a->type)
        {
        case TYPE_FLOAT:
                printf("TYPE_FLOAT:  %f\n", a->t_float.payload);
                break;
        case TYPE_STRING:
                printf("TYPE_STRING:  %s\n", a->t_string.payload);
                break;
        default:
                printf("Wrong type '%d'\n", a->type);
                return(-1);
                break;
        }

        return(0);
}

int main(int argc, char *argv[])
{
        type_float tf={TYPE_FLOAT, 3.14159 };
        type_string ts={TYPE_STRING, "HEY GUYS"};
        dosomething((alltypes *)&tf);
        dosomething((alltypes *)&ts);
        return(0);
}