Awk operation

1、 Get the remaining size of the root partition

df -h | tail -1 | awk '{print $4}'

2、 Get the current machine ip Address

ifconfig ens160 | head -2 |  awk '{print $2}'| grep "^1"

3、 According to the statistics apache Of access.log The most visited 5 individual IP

awk '{print $1}' | sort -n |unip -c | tail -5  /access.log

4、 Print /etc/passwd in UID Greater than 500 And uid

awk -F : '$3>500{print $3}' /etc/passwd

5、/etc/passwd The match contains root or net or ucp Any line of

awk -F : '/(root|net|ucp)/ {print $0}' /etc/passwd

6、 Process the following documents , Take out the domain name and count and sort it according to the domain name ( Baidu Sohu interview questions )

test.txt

http://www.baidu.com/index.html

http://www.baidu.com/1.html

http://post.baidu.com/index.html

http://mp3.baidu.com/index.html

http://www.baidu.com/3.html

http://post.baidu.com/2.html

awk -F / '{print $3}' test.txt | sort | uniq -c | sort -n

7、 Please print out /etc/passwd The first domain , And add “ User account number ：”

awk -F : '{print " The user account ："$1}' /etc/passwd

8、 Please print out /etc/passwd The third domain and the fourth domain

awk -F : '{print $3 " " $4}' /etc/passwd

9、 Please print the first field , And the print header information is ： This is the system user , Print the tail information as :“================”

awk -F : 'BEGIN{print " This is the system user "}{print $1}END{print "================"}' /etc/passwd

10、 Please print out the first field matching daemon Information about .

awk -F : '$1=="daemon"' /etc/passwd

11、 Please put /etc/passwd Medium root Replace with gongda, Remember to temporarily replace the output screen to see the effect .

awk -F: 'gsub(/root/,"gongda")' /etc/passwd

12、 Please match passwd The last field bash The message at the end , How many

awk -F: '$NF~/bash$/{print NR}' /etc/passwd | wc -l

13、 Please match at the same time passwd In file , belt mail or bash Keyword information

awk -F: '/root|mail/' /etc/passwd