Uses unsigned long long, goes up to ULONG_LONG_MAX.

Intel Core Duo 2 processor, running Cygwin on Windows XP, and compiled using gcc 3.4.4. Stops at first million results due to time. Can reasonably get to 10 million, if you’re willing to wait.

#include <stdio.h>
#include <math.h>
#include <limits.h>

int main(int argc, char **argv)
{
    unsigned long long divisor, max_divisor, prime_test;
    int break_time = 0;

    printf("%llun", 2LL);
    for(prime_test = 3LL; prime_test < ULONG_LONG_MAX; prime_test+=2LL)
    {
        max_divisor=1LL+sqrt(prime_test);
        for(divisor=3LL;divisor <= max_divisor; divisor+=2LL)
        {
            if(prime_test % divisor == 0)
            {
                break;
            }
        }
        if(divisor >= max_divisor)
        {
            printf("%llun", prime_test);
        }
        else
        {
            continue;
        }
        break_time++;
        if(break_time == 999999)
        {
            break;
        }
    }
    return 0;
}