1、了解GPL(v1、v2、v3)、LGPL、Apache、BSD、MIT等开源协定的具体内容。
答：
BSD：不允许用作者名字打广告，可商业化
Apache Licence2.0：注明修改处，可商业化
GPL：开源、免费。禁止商业化
LGPL：适合作为第三方类库，可商业化
2、使用echo如何显示“The year is 2017.\nToday is monday”为两行？
答：
[root@little ~]# echo -e "The year is 2017.\nToday is monday"
The year is 2017.
Today is monday
3、使用printf命令如何显示“ling little”为两行？
答：
[root@little ~]# printf "ling\nlittle\n"
ling
little
4、通过man获得帮助，创建目录(如有精力，可以尝试只使用一次mkdir命令解决此问题)
(1)在/mnt下创建boot和sysroot；
(2)在/mnt/boot下创建grub；
(3)在/mnt/sysroot下创建proc, sys, bin, sbin, lib, usr, var, etc, dev, home, root, tmp
a)在/mnt/sysroot/usr下创建bin, sbin, lib
b)在/mnt/sysroot/lib下创建modules
c)在/mnt/sysroot/var下创建run, log, lock
d)在/mnt/sysroot/etc下创建init.d
答：
[root@little ~]# mkdir -pv /mnt/{boot/grub,sysroot/{proc,sys,bin,sbin,lib/modules,lib64,usr/{bin,sbin/lib},var/{run,log,lock},etc/init.d,dev,home,root,tmp}}
mkdir: 已创建目录 "/mnt/boot"
mkdir: 已创建目录 "/mnt/boot/grub"
mkdir: 已创建目录 "/mnt/sysroot"
mkdir: 已创建目录 "/mnt/sysroot/proc"
mkdir: 已创建目录 "/mnt/sysroot/sys"
mkdir: 已创建目录 "/mnt/sysroot/bin"
mkdir: 已创建目录 "/mnt/sysroot/sbin"
mkdir: 已创建目录 "/mnt/sysroot/lib"
mkdir: 已创建目录 "/mnt/sysroot/lib/modules"
mkdir: 已创建目录 "/mnt/sysroot/lib64"
mkdir: 已创建目录 "/mnt/sysroot/usr"
mkdir: 已创建目录 "/mnt/sysroot/usr/bin"
mkdir: 已创建目录 "/mnt/sysroot/usr/sbin"
mkdir: 已创建目录 "/mnt/sysroot/usr/sbin/lib"
mkdir: 已创建目录 "/mnt/sysroot/var"
mkdir: 已创建目录 "/mnt/sysroot/var/run"
mkdir: 已创建目录 "/mnt/sysroot/var/log"
mkdir: 已创建目录 "/mnt/sysroot/var/lock"
mkdir: 已创建目录 "/mnt/sysroot/etc"
mkdir: 已创建目录 "/mnt/sysroot/etc/init.d"
mkdir: 已创建目录 "/mnt/sysroot/dev"
mkdir: 已创建目录 "/mnt/sysroot/home"
mkdir: 已创建目录 "/mnt/sysroot/root"
mkdir: 已创建目录 "/mnt/sysroot/tmp"
5、创建目录/backup
复制目录/etc至/backup目录中，要求保留文件原来的属性，保持链接文件；
答：
[root@little ~]# mkdir -pv /backup
mkdir: 已创建目录 "/backup"
[root@little ~]# mv /etc /backup
[root@little ~]# echo $?
0
[root@little ~]# ls /backup/
etc
3、通过man帮助手册，自行总结which、whereis、whatis命令的使用方法；
答：
which：命令的别名
whereis：命令的路径
whatis：命令作用
[root@little ~]# which ls
alias ls='ls --color=auto'
/bin/ls
[root@little ~]# whereis ls
ls: /bin/ls /usr/share/man/man1p/ls.1p.gz /usr/share/man/man1/ls.1.gz
4、通过帮助手册，学习使用du命令；并思考：如何显示某个目录内部的所有文件的整体大小？
答：
du：显示目录大小
[root@little ~]# du
12 ./test
36 ./apr-util-1.5.4/hooks/.libs
88 ./apr-util-1.5.4/hooks
88 ./apr-util-1.5.4/memcache/.libs
228 ./apr-util-1.5.4/memcache
……
[root@little ~]# du ./test
12 ./test
5、通过帮助手册，学习who、w、whoami命令，并对比who和w，思考其区别；
答：
who：登录用户
w：显示用户信息，更加详细
whoami：显示ID为0的用户信息
[root@little ~]# who
little tty1 2017-11-13 13:27 (:0)
root pts/0 2017-11-13 13:29 (172.16.1.1)
[root@little ~]# w
13:51:50 up 25 min, 2 users, load average: 0.01, 0.01, 0.00
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
[root@little ~]# whoami
whoami：无法找到用户ID 为0 的用户名
6、显示/etc目录下，以字母开头，后面跟了一个非字母及其它任意长度任意字符的文件或目录；
答：
[root@little ~]# ls /etc | grep "^[[:alpha:]][^[:alpha:]].*"
X11
[root@little ~]# ls -d /etc/[[:alpha:]][^[:alpha:]]*
/etc/X11
7、显示/usr/share/man目录下，所有以man开头，后跟一个数字结尾的文件或目录；
答：
[root@little ~]# ls -d /usr/share/man/man[0-9]
/usr/share/man/man1 /usr/share/man/man4 /usr/share/man/man7
/usr/share/man/man2 /usr/share/man/man5 /usr/share/man/man8
/usr/share/man/man3 /usr/share/man/man6 /usr/share/man/man9
[root@little ~]#
[root@little ~]# ls -d /usr/share/man/man[[:digit:]]
/usr/share/man/man1 /usr/share/man/man4 /usr/share/man/man7
/usr/share/man/man2 /usr/share/man/man5 /usr/share/man/man8
/usr/share/man/man3 /usr/share/man/man6 /usr/share/man/man9
8、复制/etc目录下，所以p,m,r开头的，且以.conf结尾的文件或目录至/tmp/conf.d目录下；
答：
[root@little ~]# ls /etc/[pmr]*.conf
/etc/mke2fs.conf /etc/pnm2ppa.conf /etc/request-key.conf
/etc/mtools.conf /etc/prelink.conf /etc/resolv.conf
/etc/pbm2ppa.conf /etc/readahead.conf /etc/rsyslog.conf
/etc/pm-utils-hd-apm-restore.conf /etc/reader.conf
[root@little ~]#
[root@little ~]# cp -a /etc/[pmr]*.conf /tmp
[root@little ~]#
[root@little ~]# ls /tmp
keyring-Hw528X keyring-rjErX0 pnm2ppa.conf
keyring-KphV2t keyring-sNGWZe prelink.conf
keyring-NtnoIW keyring-seupBP pulse-CCOJSbg2rrUT
keyring-SD8DuM keyring-va5YXr pulse-kxE14xec0BgA
keyring-SWLHv8 keyring-w9r8Y2 pulse-nMz1VNv72M1x
keyring-Ta3gEf keyring-yT4OZn readahead.conf
keyring-akJZHb mke2fs.conf reader.conf
keyring-dFQOvC mtools.conf request-key.conf
keyring-g403YF orbit-gdm resolv.conf
keyring-hosyK7 orbit-little rsyslog.conf
keyring-hpmuXh pbm2ppa.conf virtual-little.QpKRpK
keyring-rEePKI pm-utils-hd-apm-restore.conf virtual-little.hPZ8F7
9、创建a123, cd6, c78m, c1 my, m.z, k 67, 8yu, 789等文件，并按照下述要求写出相应的命令；
注意，以上文件是以逗号隔开的，其它符号都是文件名的组成部分；
1) 显示所有以a或m开头的文件；
2) 显示所有文件名中包含了数字的文件；
3) 显示所有以数字结尾且文件名中包含空白字符的文件；
4) 显示文件名中不以c字母开头并且不以数字结尾的所有文件；
答：
错误创建如下：（空格将其分开，产生错误）
[root@little ~]# touch {a123,cd6,c78m,c1 my,m.z,k 67,8yu,789}
[root@little ~]#
[root@little ~]# ls
2.txt cdrom //my,m.z,k ????????? ??????
3.txt dest t1file.txt ?????? ??????
//67,8yu,789} install.log zhengshu ??????
anaconda-ks.cfg install.log.syslog //{a123,cd6,c78m,c1 ??????
boot.iso ks.cfg ?????? ??????
正确创建如下：（处理空格，注释掉空格）
[root@little ~]# touch {a123,cd6,c78m,'c1 my',m.z,'k 67',8yu,789}
[root@little ~]#
[root@little ~]# ls
2.txt anaconda-ks.cfg cdrom ks.cfg ????????? ??????
3.txt boot.iso dest m.z ?????? ??????
789 c1 my install.log t1file.txt ??????
8yu c78m install.log.syslog zhengshu ??????
a123 cd6 k 67 ?????? ??????
1)、
[root@little ~]# ls [am]*
a123 anaconda-ks.cfg m.z
2)、
[root@little ~]# ls *[0-9]*
2.txt 3.txt 789 8yu a123 c1 my c78m cd6 k 67 t1file.txt
3)、
[root@little ~]# ls *[[:space:]]*[0-9]
k 67
4)、
[root@little ~]# ls ^c*[^[:digit:]]
ls: cannot access ^c*[^[:digit:]]: No such file or directory
[root@little ~]#
[root@little ~]# ls [^c]*[^[:digit:]]
2.txt 8yu boot.iso install.log.syslog m.z
3.txt anaconda-ks.cfg install.log ks.cfg t1file.txt
10、统计/usr/bin/目录下的文件个数；
答：
[root@little ~]# ls /usr/bin | wc -l
1940
11、取出/etc/passwd文件中第9至第15个用户的信息，并将其保存至/tmp/users文件中；
答：
[root@little ~]# head -n 15 /etc/passwd | tail -n 7 > /tmp/users
[root@little ~]#
[root@little ~]# cat /tmp/users
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
uucp:x:10:14:uucp:/var/spool/uucp:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
gopher:x:13:30:gopher:/var/gopher:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
12、显示/etc目录下所有以.conf结尾的文件或目录，并统计其个数。
答：
[root@little ~]# ls /etc/*.conf
/etc/Trolltech.conf /etc/nfsmount.conf
/etc/asound.conf /etc/nsswitch.conf
/etc/autofs.conf /etc/ntp.conf
/etc/autofs_ldap_auth.conf /etc/oddjobd.conf
/etc/cas.conf /etc/openct.conf
/etc/dnsmasq.conf /etc/pbm2ppa.conf
/etc/dracut.conf /etc/pm-utils-hd-apm-restore.conf
/etc/fprintd.conf /etc/pnm2ppa.conf
/etc/gai.conf /etc/prelink.conf
/etc/grub.conf /etc/readahead.conf
/etc/gssapi_mech.conf /etc/reader.conf
/etc/hba.conf /etc/request-key.conf
/etc/host.conf /etc/resolv.conf
/etc/idmapd.conf /etc/rsyslog.conf
/etc/kdump.conf /etc/sestatus.conf
/etc/krb5.conf /etc/smartd.conf
/etc/latrace.conf /etc/sos.conf
/etc/ld.so.conf /etc/sudo-ldap.conf
/etc/libaudit.conf /etc/sudo.conf
/etc/libuser.conf /etc/sysctl.conf
/etc/logrotate.conf /etc/updatedb.conf
/etc/ltrace.conf /etc/warnquota.conf
/etc/mke2fs.conf /etc/yp.conf
/etc/mtools.conf /etc/yum.conf
/etc/named.conf
[root@little ~]#
[root@little ~]# ls /etc/*.conf | wc -l
49
13、把/etc/passwd文件最后三行信息中所有小写字符改为大写，并且删除所有的":"、"/"以及数字字符；
答：
[root@little ~]# cat /etc/passwd | tail -n 3
little:x:500:500:little:/home/little:/bin/bash
mysql:x:27:27:MySQL Server:/var/lib/mysql:/bin/bash
named:x:25:25:Named:/var/named:/sbin/nologin
[root@little ~]#
[root@little ~]# cat /etc/passwd | tail -n 3 | tr a-z A-Z
LITTLE:X:500:500:LITTLE:/HOME/LITTLE:/BIN/BASH
MYSQL:X:27:27:MYSQL SERVER:/VAR/LIB/MYSQL:/BIN/BASH
NAMED:X:25:25:NAMED:/VAR/NAMED:/SBIN/NOLOGIN
[root@little ~]#
[root@little ~]# cat /etc/passwd | tail -n 3 | tr a-z A-Z | tr -d "':';'/';[0-9]"
LITTLEXLITTLEHOMELITTLEBINBASH
MYSQLXMYSQL SERVERVARLIBMYSQLBINBASH
NAMEDXNAMEDVARNAMEDSBINNOLOGIN
14、取出/etc/fstab的第6行； //注意，空行也算一行
答：
[root@little ~]# cat /etc/fstab | head -n 6 | tail -n 1
# Accessible filesystems, by reference, are maintained under '/dev/disk'
15、取出/etc目录下所有以s开头的文件或目录，将其中最前面的8个文件保存到/tmp/start_with_s.out并同时进行标准输出；
答：
[root@little ~]# ls -d /etc/s*
/etc/samba /etc/shadow /etc/statetab.d
/etc/sane.d /etc/shadow- /etc/sudo-ldap.conf
/etc/sasl2 /etc/shells /etc/sudo.conf
/etc/scl /etc/skel /etc/sudoers
/etc/securetty /etc/smartd.conf /etc/sudoers.d
/etc/security /etc/sos.conf /etc/sysconfig
/etc/selinux /etc/sound /etc/sysctl.conf
/etc/services /etc/ssh /etc/system-release
/etc/sestatus.conf /etc/ssl /etc/system-release-cpe
/etc/setuptool.d /etc/sssd
/etc/sgml /etc/statetab
[root@little ~]#
[root@little ~]# ls -d /etc/s* | head -8
/etc/samba
/etc/sane.d
/etc/sasl2
/etc/scl
/etc/securetty
/etc/security
/etc/selinux
/etc/services
[root@little ~]# ls -d /etc/s* | head -8 > /tmp/start_with_s.out
[root@little ~]#
[root@little ~]# cat /tmp/start_with_s.out
/etc/samba
/etc/sane.d
/etc/sasl2
/etc/scl
/etc/securetty
/etc/security
/etc/selinux
/etc/services
16、将目录/etc备份至/backup目录中，并重命名为“etc-当前日期_当前时间”，如etc-2013-02-26_20:46:30；要求保留文件原来的属性，保持链接文件；
答：
[root@little ~]# cp -a /etc /backup/etc-2017-11-15_16:43:00
cp: cannot create directory `/backup/etc-2017-11-15_16:43:00': No such file or directory
[root@little ~]# mkdir /backup
[root@little ~]# ls /
backup boot etc lib lost+found misc net proc sbin srv tmp var
bin dev home lib64 media mnt opt root selinux sys usr
[root@little ~]# cp -a /etc /backup/etc-2017-11-15_16:43:00
[root@little ~]#
[root@little ~]# ls /backup/
etc-2017-11-15_16:43:00
17、使用touch命令基于花括号展开的方式创建如下文件：ace acf acg ade adf adg bce bcf bcg bde bdf bdg
答：
[root@little ~]# touch {a,b}{c,d}{e,f,g}
[root@little ~]# ls
2.txt acf bce boot.iso install.log zhengshu ??????
3.txt acg bcf c1 my install.log.syslog ?????? ??????
789 ade bcg c78m k 67 ????????? ??????
8yu adf bde cd6 ks.cfg ??????
a123 adg bdf cdrom m.z ??????
ace anaconda-ks.cfg bdg dest t1file.txt ??????
18、创建用户xiaoding，使用centos和varnish作为附属组，并将其家目录设置于/ysu；使用xiaoding用户登录到系统，在其家目录中创建名为projects的目录，并在该目录中创建demand、design、plan、project、report_bugs等文件。后来出于统一管理需要，再将其家目录迁移至/home/ysu目录中；
答：
[root@little ~]# groupadd centos
[root@little ~]# groupadd varnish
[root@little ~]# tail -2 /etc/group
centos:x:501:
varnish:x:502:
[root@little ~]# useradd xiaoding -G centos,varnish -d /ysu
[root@little ~]#
[root@little ~]# echo "18716022695" | passwd --stdin xiaoding
Changing password for user xiaoding.
passwd: all authentication tokens updated successfully.
[root@little ~]#
[root@little ~]# tail -3 /etc/group
centos:x:501:xiaoding
varnish:x:502:xiaoding
xiaoding:x:503:
[root@little ~]# id xiaoding
uid=501(xiaoding) gid=503(xiaoding) groups=503(xiaoding),501(centos),502(varnish)
[root@little ~]#
[root@little ~]# su - xiaoding
-bash: warning: setlocale: LC_CTYPE: cannot change locale (en_CN.UTF-8): No such file or directory
-bash: warning: setlocale: LC_COLLATE: cannot change locale (en_CN.UTF-8): No such file or directory
-bash: warning: setlocale: LC_MESSAGES: cannot change locale (en_CN.UTF-8): No such file or directory
-bash: warning: setlocale: LC_NUMERIC: cannot change locale (en_CN.UTF-8): No such file or directory
-bash: warning: setlocale: LC_TIME: cannot change locale (en_CN.UTF-8): No such file or directory
[xiaoding@little ~]$
[xiaoding@little ~]$ ls
[xiaoding@little ~]$
[xiaoding@little ~]$ mkdir -pv projects
mkdir: created directory `projects'
[xiaoding@little ~]$ ls
projects
[xiaoding@little ~]$ touch projects/{demand,design,plan,project,report_bugs}
[xiaoding@little ~]$ ls projects/
demand design plan project report_bugs
[xiaoding@little ~]$
19、以下所有命令均为使用ling用户登录后，临时以root用户的身份完成，命令执行成功之后立即返回ling用户环境；
1)创建用户gentoo，UID为5000，基本组为centos，附加组为distro和peguin；
2)创建用户fedora，其全名为"Fedora Core"，附加组为distro和peguin，默认shell为/bin/tcsh；
3)将用户gentoo的附加组修改为bin和root，默认shell为/bin/csh，注释信息为"Gentoo Distribution"；
4)为用户fedora添加新的附属组centos，使得其隶属于四个组中；
5)创建系统用户iscsi，指定其UID为808，其主组是GID为808的系统组mydisk，并使其不可交互登录系统，且不为其创建家目录；
6)由于gentoo用户出差一个月，所以直到其回公司之前，禁止其登录系统，你有几种方式解决此问题？请尽可能多的写出来。
答：
（6）：
1)：# usermod -L gentoo
2): # passwd -l gentoo
//用来锁账户
3): # vim /etc/shadow
gentoo:!$6$ata(fd$adfa
4): # usermod -s /sbin/nologin gentoo
5): # chsh -s /sbin/nologin gentoo
//改变登录shell
6): # usermod -e 2017-02-04 gentoo
答：
[root@little ~]# groupadd distro;groupadd peguin
[root@little ~]#
[root@little ~]# tail -2 /etc/group
distro:x:505:
peguin:x:506:
[root@little ~]#
[root@little ~]# useradd gentoo -u 5000 -g centos -G distro,peguin
[root@little ~]# tail -3 /etc/group
ling:x:504:
distro:x:505:gentoo
peguin:x:506:gentoo
[root@little ~]# echo "18716022695" | passwd --stdin gentoo
Changing password for user gentoo.
passwd: all authentication tokens updated successfully.
[root@little ~]#
[root@little ~]# tail -1 /etc/passwd
gentoo:x:5000:501::/home/gentoo:/bin/bash
[root@little ~]#
[root@little ~]# tail -5 /etc/group
varnish:x:502:xiaoding
xiaoding:x:503:
ling:x:504:
distro:x:505:gentoo
peguin:x:506:gentoo
[root@little ~]#
[root@little ~]# id gentoo
uid=5000(gentoo) gid=501(centos) groups=501(centos),505(distro),506(peguin)
[root@little ~]#
[root@little ~]# useradd fedora -c "Fedora Core" -G distro,peguin -s /bin/tcsh
[root@little ~]#
[root@little ~]# echo "18716022695" | passwd --stdin fedora
Changing password for user fedora.
passwd: all authentication tokens updated successfully.
[root@little ~]#
[root@little ~]# tail -1 /etc/passwd
fedora:x:5001:5001:Fedora Core:/home/fedora:/bin/tcsh
[root@little ~]# tail -3 /etc/group
distro:x:505:gentoo,fedora
peguin:x:506:gentoo,fedora
fedora:x:5001:
[root@little ~]# id fedora
uid=5001(fedora) gid=5001(fedora) groups=5001(fedora),505(distro),506(peguin)
[root@little ~]#
[root@little ~]# useradd -G bin,root -s /bin/csh -c "Gentoo Distribution" gentoouseradd: user 'gentoo' already exists
[root@little ~]#
[root@little ~]# id gentoo
uid=5000(gentoo) gid=501(centos) groups=501(centos),505(distro),506(peguin)
[root@little ~]#
[root@little ~]# usermod -aG centos fedora
[root@little ~]#
[root@little ~]# id fedora
uid=5001(fedora) gid=5001(fedora) groups=5001(fedora),501(centos),505(distro),506(peguin)
[root@little ~]#
[root@little ~]# groupadd -rg 808 mydisk
[root@little ~]#
[root@little ~]# tail -1 /etc/group
mydisk:x:808:
[root@little ~]#
[root@little ~]# useradd iscsi -u 808 -g mydisk -rM
[root@little ~]#
[root@little ~]# tail -1 /etc/passwd
iscsi:x:808:808::/home/iscsi:/bin/bash
[root@little ~]#
[root@little ~]# tail -1 /etc/group
mydisk:x:808:
[root@little ~]#
[root@little ~]# id iscsi
uid=808(iscsi) gid=808(mydisk) groups=808(mydisk)
[root@little ~]#
