#include <stdio.h>
#include <string.h>
#include <iostream>

// don't want the standard library's getline
//using namespace std;

int main() {
   FILE * stream = popen("sort -n | uniq > outfile", "w");

   if (nullptr == stream) {
       perror("popen");
       exit(0);
   }

   srand(time(nullptr));

   for(int i =0; i < 100; ++i) {
      fprintf(stream, "%d\n", rand() % 500);
   }

   if(-1 == pclose(stream)) {
      perror("pclose");
   }

   return 0;
}