pfds              362 usertests.c      int pfds[2];
pfds              375 usertests.c      pipe(pfds);
pfds              378 usertests.c        close(pfds[0]);
pfds              379 usertests.c        if(write(pfds[1], "x", 1) != 1)
pfds              381 usertests.c        close(pfds[1]);
pfds              386 usertests.c      close(pfds[1]);
pfds              387 usertests.c      if(read(pfds[0], buf, sizeof(buf)) != 1){
pfds              391 usertests.c      close(pfds[0]);