第十七节课操作系统正则符号

1、课堂知识回顾

1、系统文件属性 （文件类型 权限信息 用户信息 inode/block 硬链接和软链接）
find -ls -------找到数据之后显示数据的属性信息
2、系统符号信息 （基础符号）
基础符号系列： # $ ! |
引号符号系列： ‘’ " "
路径符号系列 ： ~ - .. .
重 定 向 符 号 ： > >> 2 > 2>> < <<
正确信息/错误信息 &>>/oldboy.log
正确信息/错误信息 >>/oldboy.log 2>&1
逻辑符号系列: && 先执行符号前面的命令, 命令执行正确,再执行符号后面的命令
|| 先执行符号前面的命令, 命令执行失败,再执行符号后面的命令
; 多个命令同时执行
3、系统通配符号:

• --- 匹配所有内容
  ls -l /oldboy/.txt --- 匹配以.txt结尾信息进行详细显示
  rm -rf /oldboy/ --- 删除oldboy目录中所有信息, 但是默认无法删除隐藏文件
  rm -f /oldboy/.old.txt --- 删除以old开头 .txt结尾的所有隐藏文件
  find /oldboy -name ".txt"
  find /oldboy -name "oldboy"
  find /oldboy -name "old.txt"
  {} --- 匹配序列信息
  数字序列:
  字母序列:
  组合序列:
  echo A{,2} --- A A2
  /oldboy/oldboy01/oldboy02/oldboy03/oldboy04/oldboy.txt .bak
  快速备份数据
  cp /oldboy/oldboy01/oldboy02/oldboy03/oldboy04/oldboy.txt{,.bak}
  cp /oldboy/oldboy01/oldboy02/oldboy03/oldboy04/oldboy.txt /oldboy/oldboy01/oldboy02/oldboy03/oldboy04/oldboy.txt.bak
  快速还原数据
  cp /oldboy/oldboy01/oldboy02/oldboy03/oldboy04/oldboy.txt{.bak,}
  cp /oldboy/oldboy01/oldboy02/oldboy03/oldboy04/oldboy.txt.bak /oldboy/oldboy01/oldboy02/oldboy03/oldboy04/oldboy.txt
  cp messages{-20190707,}
  4、系统正则符号：grep sed awk
  基础正则: basic regular expression BRE
  扩展正则: extended regular expression ERE
  终极目标:

1. 文件test.txt
   张三 110106198803076651
   李四 106106199903076651
   王五 oldboy

   grep -vE "[0-9]+" test.txt

   王五 oldboy
   文件内容做修改
   张三 110106198803076651
   李四 106106199903076651
   王五 10101010100101
   周六 101010101010220101010
   grep -E "[0-9X]{18}" test.txt --- 将身份输入不足18位的进行排除

   如何找出不合理身份证人员信息

   2. 如何取出IP地址信息

   基础正则:
   ^ --- 以什么开头的信息
   # ll /etc/|grep "^d"
   drwxr-xr-x. 3 root root 101 Jul 3 20:25 abrt
   drwxr-xr-x. 2 root root 252 Jul 17 18:13 alternatives
   drwxr-x---. 3 root root 43 Jul 3 20:26 audisp
   ' /etc/selinux/config
   SELINUX=disabled
   SELINUXTYPE=targeted
   说明: 如果结尾有空格信息, 过滤是会出现异常
   利用底行模式 :set list 可以查看结尾空格信息
   利用命令查看 cat -A /etc/selinux/config
   问题: 将以点结尾的信息过滤出来:
   grep '.oldboy.txt [root@oldboyedu ~]# cat oldboy.txt oldboy01 oldboy02 ^"> --- 空行信息
   grep -v "^$" /etc/selinux/config

   . --- 匹配任意一个且只有一个字符
   grep "^." /etc/selinux/config --- 匹配任意一个以什么开头的字符
   grep ".$" /etc/selinux/config --- 匹配任意一个以什么结尾的字符
   grep "." /etc/selinux/config --- 匹配整个文件所有任意字符
   总结匹配筛选文件信息:
   01. 会按照行进行匹配
   02. 会匹配信息贪婪特性
   03. 利用grep -o可以查看匹配信息的过程

   • --- 匹配前一个字符连续出现0次或者多次
     创建一个测试文件:
     创建测试文件:
     I am oldboy teacher!
     I teach linux.

     I like badminton ball ,billiard ball and chinese chess!
     my blog is http://oldboy.blog.51cto.com
     our site is http://www.etiantian.org
     my qq num is 49000448.

     not 4900000448.
     my god ,i am not oldbey,but OLDBOY!

     匹配文件中数字0信息
     [root@oldboyedu oldboy]# grep "0*" oldboy.txt
     I am oldboy teacher!
     I teach linux.

     I like badminton ball ,billiard ball and chinese chess!
     my blog is http://oldboy.blog.51cto.com
     our site is http://www.etiantian.org
     my qq num is 49000448.

     not 4900000448.
     my god ,i am not oldbey,but OLDBOY!
     [root@oldboyedu oldboy]# grep -o "0*" oldboy.txt
     000
     00000

   .* --- 匹配文件中所有信息
   [root@oldboyedu oldboy]# grep ".*" oldboy.txt -o
   I am oldboy teacher!
   I teach linux.
   I like badminton ball ,billiard ball and chinese chess!
   my blog is http://oldboy.blog.51cto.com
   our site is http://www.etiantian.org
   my qq num is 49000448.
   not 4900000448.
   my god ,i am not oldbey,but OLDBOY!
   [] --- 匹配中括号中任意一个字符
   [root@oldboyedu oldboy]# grep "ba" oldboy.txt --- 表示过滤一个字符串
   I like badminton ball ,billiard ball and chinese chess!
   [root@oldboyedu oldboy]# grep "[bac]" oldboy.txt
   I am oldboy teacher!
   I teach linux.
   I like badminton ball ,billiard ball and chinese chess!
   my blog is http://oldboy.blog.51cto.com
   our site is http://www.etiantian.org
   my god ,i am not oldbey,but OLDBOY!
   过滤出所有小写字母:
   grep "[a-z]" oldboy.txt --- 过滤小写字母
   grep "[A-Z]" oldboy.txt --- 过滤大写字母
   grep "[a-zA-Z]" oldboy.txt --- 过滤所有字母
   grep "[a-Z]" oldboy.txt --- 过滤所有字母
   grep -i "[a-z]" oldboy.txt --- grep忽略大小写进行过滤
   [^] --- 将指定字符信息,进行取反过滤
   [root@oldboyedu oldboy]# grep -v "[a-Z]" oldboy.txt
   [root@oldboyedu oldboy]# grep "[^a-Z]" oldboy.txt
   I am oldboy teacher!
   I teach linux.
   I like badminton ball ,billiard ball and chinese chess!
   my blog is http://oldboy.blog.51cto.com
   our site is http://www.etiantian.org
   my qq num is 49000448.
   not 4900000448.
   my god ,i am not oldbey,but OLDBOY!
   系统扩展正则 (高级符号) grep --> egrep/grep -E sed --> sed -r

   • --- 匹配前一个字符连续出现1次或者多次
     grep "0*" oldboy.txt
     I am oldboy teacher!
     I teach linux.

     I like badminton ball ,billiard ball and chinese chess!
     my blog is http://oldboy.blog.51cto.com
     our site is http://www.etiantian.org
     my qq num is 49000448.

     not 4900000448.
     my god ,i am not oldbey,but OLDBOY!
     egrep "0+" oldboy.txt
     our site is 0 http://www.etiantian.org
     my qq num is 49000448.
     not 4900000448.
     | --- 匹配多个字符串信息
     匹配oldboy和oldbey单词信息
     grep "oldb[oe]y" oldboy.txt
     grep "oldb.y" oldboy.txt
     egrep "oldboy|oldbey" oldboy.txt
     企业应用: 配置文件有注释有空行, 如何进行取消
     grep -vE "^$|#" /etc/services
     () --- 将多个字符信息进行整合过滤 难点
     实现后项引用前项进行替换 常用
     第一个作用实践说明
     [root@oldboyedu oldboy]# grep [old] oldboy.txt
     I am oldboy teacher!
     I teach linux.
     I like badminton ball ,billiard ball and chinese chess!
     my blog is http://oldboy.blog.51cto.com
     our site is 0 http://www.etiantian.org
     not 4900000448.
     my god ,i am not oldbey,but OLDBOY!
     [root@oldboyedu oldboy]# egrep "(old)" oldboy.txt
     I am oldboy teacher!
     my blog is http://oldboy.blog.51cto.com
     my god ,i am not oldbey,but OLDBOY!

     第二个作用: 配合sed命令使用时,可以实现后项引用前项
     echo "123456"|sed -r 's#([0-9]+)#<\1>#g'
     <123456>
     echo "1234567890"|sed -r 's#([0-9])#<\1>#g'
     echo "789"|sed -r 's#(.)(.)(.)#<\1><\2><\3>#g'
     <7><8><9>
     说明: 后项引用前项只能引用1-9个小括号

     解锁: 批量创建用户 (密码是随机密码)
     [root@oldboyedu oldboy]# seq -w 10|sed -r 's#(.)#useradd oldboy\1;echo 123456|passwd --stdin oldboy\1#g'
     useradd oldboy01;echo 123456|passwd --stdin oldboy01
     useradd oldboy02;echo 123456|passwd --stdin oldboy02
     useradd oldboy03;echo 123456|passwd --stdin oldboy03
     useradd oldboy04;echo 123456|passwd --stdin oldboy04
     useradd oldboy05;echo 123456|passwd --stdin oldboy05
     useradd oldboy06;echo 123456|passwd --stdin oldboy06
     useradd oldboy07;echo 123456|passwd --stdin oldboy07
     useradd oldboy08;echo 123456|passwd --stdin oldboy08
     useradd oldboy09;echo 123456|passwd --stdin oldboy09
     useradd oldboy10;echo 123456|passwd --stdin oldboy10
     [root@oldboyedu oldboy]# seq -w 10|sed -r 's#(.)#useradd oldboy\1;echo 123456|passwd --stdin oldboy\1#g'|bash
     Changing password for user oldboy01.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy02.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy03.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy04.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy05.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy06.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy07.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy08.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy09.
     passwd: all authentication tokens updated successfully.
     Changing password for user oldboy10.
     passwd: all authentication tokens updated successfully.

     问题:
     echo "1234567890"|sed -r 's#(.)(.)(.)(.)(.)(.)(.)(.)(.)(.)#<\1><\2><\3><\4><\5><\6><\7><\8><\9><(\10)>#g'
     <1><2><3><4><5><6><7><8><9><(10)>

   {} 匹配前一个字符连续出现指定的次数
   {n,m} --- 匹配前一个字符连续出现至少n次 最多m次
   [root@oldboyedu oldboy]# grep -E "0{2,4}" oldboy.txt
   my qq num is 49000448.
   not 4900000448.
   [root@oldboyedu oldboy]# grep -E "0{2,4}" oldboy.txt -o
   000
   0000
   [root@oldboyedu oldboy]# grep -E "0{1,3}" oldboy.txt -o
   0
   000
   000
   00
   [root@oldboyedu oldboy]# grep -E "0{1,3}" oldboy.txt
   our site is 0 http://www.etiantian.org
   my qq num is 49000448.
   not 4900000448.
   {n} --- 匹配前一个字符连续出现正好n次
   [root@oldboyedu oldboy]# grep -E "0{3}" oldboy.txt
   my qq num is 49000448.
   not 4900000448.
   [root@oldboyedu oldboy]# grep -E "0{2}" oldboy.txt
   my qq num is 49000448.
   not 4900000448.
   {n,} --- 匹配前一个字符连续出现最少n次, 最多不限
   {,m} --- 匹配前一个字符连续出现最少0次, 最多是m次
   [root@oldboyedu oldboy]# grep -E "0{3,}" oldboy.txt
   my qq num is 49000448.
   not 4900000448.
   [root@oldboyedu oldboy]# grep -E "0{,3}" oldboy.txt
   I am oldboy teacher!
   I teach linux.
   I like badminton ball ,billiard ball and chinese chess!
   my blog is http://oldboy.blog.51cto.com
   our site is 0 http://www.etiantian.org
   my qq num is 49000448
   not 4900000448.
   my god ,i am not oldbey,but OLDBOY!
   ? --- 匹配前一个字符连续出现0次或者1次
   总结: * + {} ?
   [root@oldboyedu oldboy]# egrep "o*" test02.txt
   gd
   god
   good
   goood
   gooood
   [root@oldboyedu oldboy]# egrep "o+" test02.txt
   god
   good
   goood
   gooood
   [root@oldboyedu oldboy]# egrep "o?" test02.txt
   gd
   god
   good
   goood
   gooood
   [root@oldboyedu oldboy]# egrep "o?" test02.txt -o
   o
   o
   o
   o
   o
   o
   o
   o
   o
   o

   总结:
   通配符号: 匹配文件名称信息
   正则符号: 匹配文件内容信息