Linux第四周作业20191222

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

cat /etc/passwd | grep /sbin/nologin| awk -F":" '{print $1}'

2、查出用户UID最大值的用户名、UID及shell类型

sort -n -k3 -t’:’ /etc/passwd|tail -1f|cut -d: -f1,3,7

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

netstat -tun | grep ESTABLISH |cut -d: -f6 | sort -nr | uniq -c

4、编写脚本 createuser.sh，实现如下功能:使用一个用户名做为参数，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

#!/bin/bash

read -p "Create user :" USERNAME

if id -u $USERNAME; then

    echo "${USERNAME} already exists!"

else

    useradd ${USERNAME} &&

    id ${USERNAME}

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，时间，描述等

原答案：

#!/bin/bash

##################################

#Filename:

#Description:

#Date:`date +%F`

#Author:

#Version:

#####################################

[ $# -gt 1 ]&&echo "arg must be three:the first one is FILENAME,the second one is AUTHOR,the third is VERSION"&&exit 1

[ $# -eq 0 ]&&read -p "please input FILENAME,AUTHOR and VERSION: " FILENAME AUTHOR VERSION

[ $# -eq 1 ]&&FILENAME=$1&&AUTHOR=$2&&VERSION=$3

[ -a "$FILENAME" ]&&echo "$FILENAME is exit"&&exit 101 

touch $FILENAME

chmod a+x $FILENAME

cat >> ${FILENAME} << EOF

#!/bin/bash

##################################

#Filename:`basename $FILENAME`

#Description:

#Date:`date +%F`

#Author:$AUTHOR

#Version:$VERSION

#####################################

EOF

vim + $FILENAME

set --

批改：

vim ～/.vimrc

set autoindent

set showmatch

set incsearch

set shiftwidth=4

autocmd BufNewFile *.sh exec ":call SetTitle()"

func SetTitle()

        if expand("%:e") == 'sh'

        call setline(1,"#!/bin/bash")

        call setline(2,"#")

        call setline(3,"#********************************************************************")

        call setline(4,"#Author:                daichengsen")

        call setline(5,"#QQ:                    476436440")

        call setline(6,"#Date:                  ".strftime("%Y-%m-%d"))

        call setline(7,"#FileName：            ".expand("%"))

        call setline(8,"#Description：          ")

        call setline(9,"#Copyright (C):        ".strftime("%Y")." All rights reserved")

        call setline(10,"#********************************************************************")

        call setline(11,"")

        endif

endfunc

autocmd BufNewFile * normal G