linux之awk使用技巧

> awk '{print $1}' rumenz.txt

> awk '{print $1,$2}' rumenz.txt

> awk '{print $NF}' rumenz.txt

> awk 'END{print NR}' rumenz.txt

> awk 'NR==1{print}' rumenz.txt

> sed -n '3,1p' rumenz.txt | awk '{print $2}'

> awk 'NF' rumenz.txt

> awk 'b=!b' rumenz.txt

> awk -F '#' 'if(NF==3){print}' rumenz.txt

> cat /etc/passwd | awk -F ":" '{print $1" : "$7}'

> cat /etc/passwd | awk '{count++}END{ print count}'

> ls -l | awk 'BEGIN{size=0}{size=size+$5}END{print size}'

> ls -l | awk 'BEGIN{size=0}{size=size+$5}END{print size}'

> netstat -tunlp | awk '/^tcp/{++a[$6]}END{for(i in a) print i,a[i]}'

> awk '/^[^$]/ {print $0}' rumenz.txt

> cat 1.txt
1
2
3

> cat 1.txt | awk '{a+=$1}END{print a}'

> cat 1.txt | awk '{a+=$1}END{print a/NR}'

> cat 1.txt | awk 'BEGIN{a=0}{if($1>a) a=$1 fi}END{print a}'