1.显示/etc目录下,以非字母开头,后面跟了一个字母以及其它任意长度任意字符的文件或目录
ls -al /etc/[^a-z][a-z]*
实例演示:
[root@centos7 ~]# ls -al /etc/[^a-z][a-z]*
ls: cannot access /etc/[^a-z][a-z]*: No such file or directory
[root@centos7 ~]# ls -al /data
total 0
drwxr-xr-x. 2 root root 43 May 10 15:55 .
dr-xr-xr-x. 18 root root 256 Apr 21 22:45 ..
-rw-r--r-- 1 root root 0 May 10 15:55 2abcd
-rw-r--r-- 1 root root 0 May 10 15:55 3a
-rw-r--r-- 1 root root 0 May 10 15:55 456abc
[root@centos7 ~]# ls -al /data/[^a-z][a-z]*
-rw-r--r-- 1 root root 0 May 10 15:55 /data/2abcd
-rw-r--r-- 1 root root 0 May 10 15:55 /data/3a
2.复制/etc目录下所有以p开头,以非数字结尾的文件或目录到/tmp/mytset1目录中
mkdir /tmp/mytest1
cp -a /etc/p*[^0-9] /tmp/mytest1/
ls -al /tmp/mytest1/
实例演示:
[root@centos7 ~]# ll /tmp/mytest1/
total 0
[root@centos7 ~]# cp -a /etc/p*[^0-9] /tmp/mytest1/
[root@centos7 ~]# ls -al /tmp/mytest1/
total 52
drwxr-xr-x 14 root root 308 May 10 16:08 .
drwxrwxrwt. 13 root root 4096 May 10 16:07 ..
drwxr-xr-x. 2 root root 4096 Mar 23 22:28 pam.d
-rw-r--r--. 1 root root 2129 Mar 19 21:52 passwd
-rw-r--r--. 1 root root 2129 Mar 19 21:52 passwd-
-rw-r--r--. 1 root root 1362 Jun 10 2014 pbm2ppa.conf
-rw-r--r--. 1 root root 2872 Jun 10 2014 pinforc
drwxr-xr-x. 10 root root 116 Mar 19 21:47 pki
drwxr-xr-x. 2 root root 28 Mar 19 21:45 plymouth
drwxr-xr-x. 5 root root 52 Mar 19 21:44 pm
-rw-r--r--. 1 root root 6300 Jun 10 2014 pnm2ppa.conf
drwxr-xr-x. 2 root root 6 Jun 10 2014 popt.d
drwxr-xr-x. 2 root root 154 Mar 19 21:47 postfix
drwxr-xr-x. 3 root root 219 Mar 19 21:45 ppp
drwxr-xr-x. 2 root root 105 Mar 19 21:46 prelink.conf.d
-rw-r--r--. 1 root root 233 Jun 7 2013 printcap
-rw-r--r--. 1 root root 1795 Nov 6 2016 profile
drwxr-xr-x. 2 root root 4096 Mar 19 21:47 profile.d
-rw-r--r--. 1 root root 6545 Jun 7 2013 protocols
drwxr-xr-x. 2 root root 79 Mar 19 21:46 pulse
drwxr-xr-x. 2 root root 23 Mar 19 21:46 purple
drwxr-xr-x. 2 root root 35 Mar 19 21:44 python
3.将/etc/issue文件中的内容转换为大写后保存至/tmp/issue.out文件中
tr [a-z] [A-Z] < /etc/issue > /tmp/issue.out
cat /tmp/issue.out
实例演示:
[root@centos7 ~]# tr [a-z] [A-Z] < /etc/issue > /tmp/issue.out
[root@centos7 ~]# cat /tmp/issue.out
\S
KERNEL \R ON AN \M
4.请总结描述用户和组管理类命令的使用方法并完成以下练习:
常用命令: useradd,usermod,userdel,groupadd,groupmod,groupdel
默认值设定参考:
/etc/default/useradd
/etc/skel/
/etc/login.defs
(1).创建组distro,其GID为2019;
groupadd -g 2019 distro
(2). 创建用户mandriva,其ID号为1005;基本组为distro;
useradd -u 1005 -g distro mandriva
(3).创建用户mageia,其ID号为1100,家目录为/home/linux;
useradd -u 1100 -d /home/linux mageia
(4).给用户mageia添加密码,密码为mageedu,并设置用户密码7天后过期
echo mageedu | passwd --stdin mageia &> /dev/null
passwd -x 7 mageia
chage -M 7 mageia
(5).删除mandriva,保留其家目录;
userdel mandriva
-r: 删除用户家目录
(6).创建用户slackware,其ID号为2002,基本组为distro,附加组peguin;
groupadd peguin
useradd -u 2002 -g distro -G peguin slackware
(7).修改slackware的默认shell为/bin/tcsh;
su - slackware
chsh -s /bin/tcsh slackware
usermod -s /bin/tcsh slackware
(8).为用户slackware新增附加组admins;
groupadd admins
usermod -aG admins slackware
来源：oschina
链接：https://my.oschina.net/u/4311438/blog/4294252