int status;

            if ( waitpid(pid, &status, 0) == -1 ) {
             perror("waitpid failed");
             return EXIT_FAILURE;
            }

            if ( WIFEXITED(status) ) {
                // final result
                const int es = WEXITSTATUS(status);
                printf("Exit status for %d(words in the sentence): %d\n Final result: ", pid, es);

                char c;
                int r;

                while((r = read(pfd4[0], &c, 1))>0)
                {
                    printf("%c", c);
                }

                printf("\n");
            }

            close(pfd4[0]);