Linux2014-期末试卷A答案

2014～2015学年第1学期期末考试试卷《Linux操作系统》（A卷共5页）（考试时间：2015年1月7日）题号一二三四五成绩核分人签字得分一、单项选择题（共20小题，每小题2分，共40分。

将答案填在题后的答题区中，写在其他位置的答案无效！）1.What is the correct command to save the output of the command in one file and the error messages in another?mand1>file12>&1mand1>file12>file2mand1>file12>file1mand2>file21>&22.Which of the following commands should be used to list all files in the root filesystem that are named.profile?A.find.-name.profileB.find/-name.profile-printC.find*-name"*profile"–lsD.find../..profile-exec ls–l3.Which of the following vi commands would display all of the current vi options?A.:set optionB.:set allC.:setD.:set list4.Which vi command is used to exit the vi editor without saving the data?A.:q!B.:e!C.:wq!D.ZZ5.Which command will display all lines in file1that contain either the string abc or the string xyz?A.grep abc file1|grep xyz file1B.grep-E"abc|xyz"file1C.grep[abc-xyz]file1D.grep^[abc|xyz]$file16.Which command should be used to start a process named"long_proc"in the background if the user logs off before the process completes?A.long_procB.long_proc&C.nohup long_procD.nohup long_proc&7.Which vi command can be used to change the location of the cursor position to line16of a file?A.16B.j16C./16D.:168.Which command will invoke the man pages for the pwd command?A.catman-w pwdB.man pwdC.man-k pwdD.man-f pwd9.What is required to use the cp command to copy multiple files to a directory?A.The last item listed for the command must be the directory.B.A full path must be specified for each item in the command list.C.The target directory must be listed first and the files follow.D.A list of file names is directed to standard in and the name of the directory is assigned to standard error.10.What is the first line of every shell script which executes by using the default shell on most linux systems?A.$/bin/shB.#!/bin/she/bin/shD.set shell=/bin/sh11.What will this statement do?export PS2=">"A.Make the color display work.B.Change the look of the command prompt.C.Change some of the terminal parameters.D.Change the secondary command line prompt.12.Fill in the blanks(x)and(y):$ln FileA FileB$ln–s FileB FileC$ls–il FileA FileB FileC8986669–rw-r--r--2test test2002010-04-2215:15FileA___(x)__–rw-r--r--(y)test test2002010-04-2215:15FileB8986670lrwxrwrwx1test test52010-04-2215:16FileC->FileBA.(x)=8986669(y)=1B.(x)=8986669(y)=2C.(x)=8986670(y)=1D.(x)=8986670(y)=213.What will"cd~/foo"do?A.It will take you to the directory foo in your home directory.B.It will create the foo directory and change to it.C.It will take you to the home directory of user foo.D.It will change the directory to the system foo directory.14.Which command is used to rename a file?A.mvB.cp-rC.rmD.touch-r15.What command would execute cmd2only if cmd1was unsuccessful?A.cmd1|cmd2B.cmd1;cmd2C.cmd1||cmd2D.cmd1&&cmd216.Which GNU tar command will decompressing a tarball compressed by gzip?A.tar-czvf filename.tgzB.tar-xzvf filename.tgzC.tar-tzvf filename.tgzD.tar-dzvf filename.tgz17.Which of the following can NOT connect three split file‘a.1’,‘a.2’,‘a.3’into one file‘a’?A.cat a.[1-3]>aB.cat a.1>a&&cat a.2>a&&cat a.3>aC.(cat a.1;cat a.2;cat a.3)>aD.cat a.1>a&&cat a.2>>a&&cat a.3>>a18.Which programs will allow you to change the priority of a program already running?A.chniceB.niceC.niceitD.renice19.If you set the umask to027,by default what permissions will your regular files have?A.----w-rwxB.rw--wxrwxC.rwxr-x---D.rw-r-----20.In bash,inserting"2>&1"after a command redirectsA.standard error to standard inputB.standard input to standard errorC.standard output to standard errorD.standard error to standard output二、填空题（共10小题，每小题2分，共20分。

将答案填在题后的答题区中，写在其他位置的答案无效！）1.Which command can be used to read the file format manual of/etc/passwd?2.How can an online user get his/her login information,such as tty and login time?3.Which directory contains the system-wide configuration files?4.Display only the lines of file1that begin with an“x”and contain a“y”.5.When installing ubuntu,you are asked to create a user account which is in/etc/sudoers.But you don’t have chance to set the root’s password.How can you reset the root’s password?6.How to copy a directory“~/dir1”and its contents to/tmp?7.Which command,without any options,can tell you what the file’s type is?8.How can you get your current shell’s pid?9.What environment variable has the return code of the last command?10.How to display“hello”and“world”in two lines in a single echo command?选择题答题区12345678910B B B A B D D B A B11121314151617181920D B A A C B B D D D填空题答题区1.__man5passwd___________________________________________________________2.who am i3.__/etc____________________________________________________________________4.grep‘^x.*y’file15.sudo passwd root6.__cp-R~/dir1/tmp_______________________________________________________7.file8.__echo$$_______________________________________________________________9.?10.echo-e“hello\nworld”三、简答题（共4道小题，每题5分，共20分）1.When finding all files which have the file names begin with“s”,we should use single quotes to surround the wild card asterisk,like:$find.-name‘s*’-printwhy should we do in this way?Is there any other meta-characters can we use instead of single quotes?答：1）find命令使用通配符作为查询条件，例如s*代表查询此目录及其子目录下所有文件名以s打头的文件。