Which of the following will occur if an operator types the command vi file.out?（）

A、If the file exists it will be opened for editing. If the file does not exist an error message will be displayed.

B、If the file exists it will be opened for editing. If the file does not exist a new file with the name file.out will be created and opened for editing.

C、If the file exists an error message will be displayed. If the file does not exist a new file with the name file.out will be created and opened for editing.

D、If the file exists the operator will be asked whether to open the file or overwrite the file. If the file does not exist a new file with the name file.out will be created and opened for editing.

A system administrator will be migrating a server from AIX 5.1 to AIX 5.2 and is uncertain if the application running on the server will function properly after the migration. What is the fastest way to return to the previous AIX level if the application does not work？（）

A、Use base media to restore system to AIX 5.1.

B、Use an alt_disk_install and boot back to the AIX 5.1 rootvg.

C、Make a mksysb of the original AIX to restore back to the AIX 5.1 level.

D、Perform the AIX 5.2 upgrade using update_all with the commit option and reject filesets to return to AIX 5.1.

已知在TFTP服务器中有一个配置文件名为startup010203，它是在01年2月3日保存的配置文件，现在想把路由器恢复为那个时候的配置状态，TFTP服务器的IP地址为192.168.1.23，应该在路由器中执行哪个命令（）？

A、copytftp：//192.168.1.23/startup010203startup-config

B、copystartup-configtftp

C、download192.168.1.23startup-config

D、copytftp：//192.168.1.23startup010203startup-config

如果经常执行类似于下面的查询语句SELECT * FROM STUDENT where substr(sname,0,2)=’陈’，应该为STUDENT表的SNAME列创建（）索引。

A、B树唯一索引

B、B树不唯一索引

C、基于函数的索引

D、位图索引

Your best customer calls in with a last-minute need for the BTU/HR or the heat output per server， per hour for a rack of x3650 servers.  What IBM tool will you use to get your answer quickly？（）

A、System x Sales Configuration Aid （xSCA）

B、BladeCenter & System x Power Configurator

C、Configuration & Options Guide - （COG）

D、IBM Sizing Guides

有以下结构体说明、变量定义和赋值语句 struct STD { 　char name[10]; 　int age; 　char sex; }s[5],*ps; ps = &s[0]; 则以下scanf函数调用语句有错误的是（　　）。

A、scanf("%s",s[0].name);

B、scanf("%d",&s[0].age);

C、scanf("%c",&(ps->sex));

D、scanf("%d",ps->age);