#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>

int  main(void) {
   pid_t childpid;

   childpid = fork();
   if (childpid == -1)  {
       perror("Failed to fork");
       return 1; 
   }
   if (childpid == 0) {                            /* child code */
       execl("/bin/ls", "ls", "-l", NULL);
       perror("Child failed to exec ls");
       return 1; 
   }
   if (childpid != wait(NULL)) {                  /* parent code */
       perror("Parent failed to wait due to signal or error");
       return 1;
   }
   return 0; 
}