#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#define MAX 512
main(int argc, char* argv[]) {
  int pd[2];
  pipe(pd);
    if(fork() == 0)
    {
        dup2(pd[1], 1);
            execvp("ls", argv);
    }
    else
    {
        wait(NULL);
        if(fork() == 0)
        {
            char buf[MAX];
            int lb, i;
            close(pd[1]);
            while((lb=read(pd[0],buf,MAX))>=0)
            {
                  for(i=0; i<lb; i++)
                        buf[i] = toupper(buf[i]);
                        write(1, buf,lb);
                exit(0);
            }
        }
        wait(NULL);
        wait(NULL);
        printf("ojciec3\n");
        printf("Koniec3\n");
    }
}