文本处理与脚本的简单编写练习

Posted 2020-12-14

1、统计出/etc/passwd文件中其默认shell为非/sbin/nologin的用户个数，并将用户都显示出来

[root@centos7 scripts]# grep -v ‘/sbin/nologin$‘ /etc/passwd |cut -d: -f1
root
sync
shutdown
halt
kyle
test

[root@centos7 ~]# awk -F: ‘{if($NF!="/sbin/nologin"){print $1}}‘ /etc/passwd
root
sync
shutdown
halt
kyle
test

[root@centos7 scripts]# sed -n  ‘/nologin/!p‘ /etc/passwd |sed -r ‘s@^([^:]+).*$@1@‘
root
sync
shutdown
halt
kyle
test

2、查出用户UID最大值得用户名、UID及shell类型

[root@centos7 scripts]# sort -n -r -t : -k 3 /etc/passwd |head -1 |cut -d: -f1,3,7
test:1006:/bin/bash

3、统计当前连接本机的每个远程主机IP的连接数，并按从大到小排序
（ss.log是附加的）

[root@centos7 scripts]# grep -v ‘State‘ ss.log |tr -s ‘ ‘|cut -d‘ ‘ -f5|awk -F: ‘{i=$1;count[i]++}END{for(i in count){print count[i],"	",i}}‘|sort -nr -k1
44   127.0.0.1
10   113.234.28.244
8    124.64.18.135
6    45.62.217.224
6    210.21.36.228
6    106.38.128.110
5    116.227.232.42
4    59.46.213.114
3    144.76.4.41
2    5.9.70.117
1    91.191.250.142
1    66.249.66.158
1    66.249.66.129
1    61.151.178.165
1    61.149.193.234
1    61.136.204.138
1    5.188.210.39
1    40.77.189.81
1    218.2.216.30
1    202.100.205.245
1    183.226.12.140
1    180.174.58.237
1    120.194.3.98
1    117.136.38.134
1    116.255.176.86
1    112.33.255.134
1    101.200.188.230
1    100.100.110.61

[root@centos7 scripts]# grep -v "State" ss.log|awk ‘{print $5}‘|cut -d: -f1 |sort|uniq -c |sort -nr -k1
     44 127.0.0.1
     10 113.234.28.244
      8 124.64.18.135
      6 45.62.217.224
      6 210.21.36.228
      6 106.38.128.110
      5 116.227.232.42
      4 59.46.213.114
      3 144.76.4.41
      2 5.9.70.117
      1 91.191.250.142
      1 66.249.66.158
      1 66.249.66.129
      1 61.151.178.165
      1 61.149.193.234
      1 61.136.204.138
      1 5.188.210.39
      1 40.77.189.81
      1 218.2.216.30
      1 202.100.205.245
      1 183.226.12.140
      1 180.174.58.237
      1 120.194.3.98
      1 117.136.38.134
      1 116.255.176.86
      1 112.33.255.134
      1 101.200.188.230
      1 100.100.110.61

4、编写脚本createuser.sh，实现如下功能：使用一个用户名作为参数，如果指定参数的用户存在，就显示其存在，否则添加之；显示添加的用户的id号等信息

[root@centos7 scripts]# vim createuser.sh 
[root@centos7 scripts]# cat createuser.sh
#!/bin/bash
#
#**********************************************#
#Author:        kyle
#QQ:            1923803824
#Date:          2020-07-05
#FileName:        createuser.sh
#Description:    The test script
#Copyright (C)    2020 All rights reserved
#**********************************************#
[ $# -gt 1 -o $# -eq 0 ] && { echo "Usge: `basename $0` USERNAME" && exit 1; }
id $1 &> /dev/null
if [ $? -eq 0 ];then
    echo "$1 is existed"
else
    useradd $1 &>/dev/null && echo "$1 is created! "
    echo "$1 userinfo: `grep $1 /etc/passwd | cut -d: -f1,3,7`"
fi

5、编写生成脚本基本格式的脚本，包括作者，联系方式，版本，描述等

[root@Centos7 ~]# vim .vimrc
[root@Centos7 ~]# cat .vimrc
set tabstop=4                    #指定tab缩进的4个字符
set softtabstop=4                #定义tab所等同的空格长度      
set shiftwidth=4                 #自动缩进所使用的空白长度；建议以上三项设置数值一样
set expandtab                    #tab，默认是8个空格，这里与上面三项组合，描述为以4个空格代替tab
set ignorecase                   #搜索忽略大小写
set cursorline                   #下划线突出显示当前行
set autoindent                   #自动缩进
autocmd BufNewFile *.sh exec ":call SetTitle()"   #当vim .sh结尾的文件，就会调用SetTitle函数
func SetTitle()                  #SetTitle函数
    if expand("%:e") == ‘sh‘     #判断后缀是否为sh
    call setline(1,"#!/bin/bash")
    call setline(2,"#")
    call setline(3,"#**********************************************#")
    call setline(4,"#Author:        kyle")
    call setline(5,"#QQ:            1923803824")
    call setline(6,"#Date:          ".strftime("%Y-%m-%d"))
    call setline(7,"#FileName:        ".expand("%"))
    call setline(8,"#Description:    The test script")
    call setline(9,"#Copyright (C)    ".strftime("%Y")." All rights reserved")
    call setline(10,"#**********************************************#")
    call setline(11,"")
    endif
endfunc                           #函数结束
autocmd BufNewFile * normal G     #自动将光标定位到末尾

显示效果如下：