Linux--第三天

思维导图：

1、重定向练习：将根目录下的文件的文件名写入/test/file文件中

[root@localhost test]# ls /   #查看更目录下的文件名
bin   dev  home  lib64  mnt  proc  run   srv  test  usr
boot  etc  lib   media  opt  root  sbin  sys  tmp   var
[root@localhost test]# ls / > file  #使用重定向将文件名存到file文件中
[root@localhost test]# cat file   #查看file文件
bin
boot
dev
etc
home
lib
lib64
media
mnt
opt
proc
root
run
sbin
srv
sys
test
tmp
usr
var

 2、vim命令练习：将/root/.bashrc文件内容读入/test/bashrc，删除#号开头的行内容

[root@localhost test]# cat /root/.bashrc   #查看
# .bashrc

# User specific aliases and functions

alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

# Source global definitions
if [ -f /etc/bashrc ]; then
	. /etc/bashrc
fi
[root@localhost test]# cat /root/.bashrc >> bashrc  #将/root/.bashrc读入bashrc
[root@localhost test]# cat bashrc  #查看bashrc
# .bashrc

# User specific aliases and functions

alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

# Source global definitions
if [ -f /etc/bashrc ]; then
	. /etc/bashrc
fi
[root@localhost test]# vim /root/.bashrc  #进入编辑，删除#开头的行内容

在命令行输入 :g/#/d 然后enter，就删除了含有#的行

3、查看/etc/selinux/config 以 SELINUX开头的行

[root@localhost ~]# cat /etc/selinux/config

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=enforcing
# SELINUXTYPE= can take one of these three values:
#     targeted - Targeted processes are protected,
#     minimum - Modification of targeted policy. Only selected processes are protected. 
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted

[root@localhost ~]# grep ^[SELINUX] /etc/selinux/config
SELINUX=enforcing
SELINUXTYPE=targeted

4、文本处理命令：使用cut命令将当前主机的ip地址切割显示

[root@localhost ~]# ip a show ens160 | grep inet -w| tr -s " " | cut -d " " -f 3
192.168.41.129/24