#include <stdio.h>
 #include <sys/ipc.h>
 #include <sys/shm.h>
 #include <sys/types.h>
 #include <stdlib.h>

 #define BUFSIZE 100

 main()
 {
   int id;
   int foo;
   int *buf;

   /* create shared memory */
   id = shmget(1234, BUFSIZE*sizeof(int), IPC_CREAT|0600);
   if (id == -1)
   {
     perror("Error create shared memory");
     exit(1);
   }

   /* attach shared memory segment */
   buf = (int*)shmat(id, NULL, 0);
   if (buf == NULL)
   {
     perror("Error shared memory operation");
   }

   /* get memory elements */
   for (foo = 0; foo < 1000; foo++)
   {
     printf("[%d] = ( %d )\n", foo, buf[foo % BUFSIZE]);
   }
}