DVD Video Programming

I'm interested in creating programs that would run on a DVD movie, but I can't find anything remotely useful.

I found DVDAuthor, but I don't think it really suits my purposes. I need more functionality than just setting subtitles and creating menus. I want to run actual programs... like using functions, setting variables, and all that jazz. Is this feasible? It seems like it should be, since interactive games like Scene It exist, but who am I to say. I can't find a god damn bit of information on this.

If anybody knows of any tutorials or libraries on how to do more extensive programming, it would be greatly appreciated if you would share. :)

I'm always open to learning new languages.

>>21
#define __STDC_ISO_10646__  200104L
#define _GNU_SOURCE

#include <stdio.h>
#include <stdlib.h>
#include <wchar.h>
#include <locale.h>

int main(int argc, char **argv)
{
    char *buffa = NULL;
    unsigned int n;

    if (setlocale(LC_CTYPE, "") == NULL) {
        fprintf(stderr, "Locale not specified. Fix this.\n");
        return 1;
    }

    while (getline(&buffa, &n, stdin) != -1) {
        char *c = buffa;

        while (*c) {
            if ('!' <= *c && *c <= '~')
                printf("%lc", *c + 0xfee0);
            else if (*c == ' ')
                printf("%lc", 0x2003);
            else
                printf("%c", *c);

            ++c;
        }

        free(buffa);
    }

    return 0;
}