fd3 311 user/usertests.c int fd3 = open("truncfile", O_RDONLY); fd3 312 user/usertests.c n = read(fd3, buf, sizeof(buf)); fd3 314 user/usertests.c printf("aaa fd3=%d\n", fd3); fd3 328 user/usertests.c n = read(fd3, buf, sizeof(buf)); fd3 344 user/usertests.c close(fd3);