Some uses of Shell awk

#1, print the usage of the mounted directory, the default is separated by a space

df-ph | awk ' {print $5,$6} '

#2, separated by a space, colon, \ t, semicolon

Awk-f ' [: \ t;] ' ' {print '} '

#3, Print lines 3rd through 5th in the 6.txt file, nr represents the print line, and $ A is the text all fields

awk ' nr==3,nr==5 {print} ' 6.txtawk ' nr==3,nr==5 {print $} ' 6.txt

Column 2nd and 4th of line 3rd through 5th in #打印6. txt file

awk ' nr==3,nr==5 {print $2,$4} ' 6.txt

#打印7. txt file, line numbers and contents that are longer than 6

awk ' Length ($) >6 {print nr,$0} '

#以冒号切割, printing the first column shows only the first 5 rows:

Cat/etc/passwd|head-5|awk-f: ' {print '} ' awk-f: ' nr>=1&&nr<=5 {print '} '/etc/passwd

#NR行号除以2余数为0则跳过该行, proceed to the next line, print on the screen:

awk ' nr%2==0 {next} {print nr,$0} ' 7.txt

#4, reference shell variables, use-V or double quotation marks + single quotes:

Awk-v Str=hello ' {print STR, $NF} ' 7.txtstr= ' hello '; echo| awk ' {print ' ' ${str} ' ";} '

#5, the sum of the first column of the specified file Jfedu.txt:

Cat 7.txt |awk ' {sum+=$1}end{print sum} ' awk ' {sum+=$1}end{print sum} ' 7.txt

To #6, add a custom character:

Ifconfig eth0|grep "Bcast" |awk ' {print ' IP_ ' $ $} ' awk-f: ' {print ' UserName: ' $ '/etc/passwd

#7, formatted output passwd content, printf print string,% formatted output delimiter, s denotes string type, 12 is 12 characters, 6 means 6 characters:

Awk-f: ' {printf '%-12s%-6s%-8s\n ', $1,$2, $NF} '/etc/passwd

#OFS输出格式化 \ t:

Netstat-an|awk ' $6 ~/listen/&&nr>=1&&nr<=10 {print nr,$4,$5,$6} ' ofs= ' \ t '

#8, awk and if combination combat, judge the number comparison

Echo 3 2 1 | awk ' {if (($1>$2) | | | ($1>$3)) {print $ {} else {print \ {}} '

Combination of #9, awk and array combat, statistics passwd file users

Awk-f: ' BEGIN {count=0;} {Name[count] = $1;count++;}; End{for (i = 0; i < NR; i++) print I, Name[i]} '/etc/passwd

#10, awk analysis of the Nginx access log status code 404, 502 and other error information page, the number of statistics greater than 20 IP address.

awk ' {if ($9~/502|499|500|503|404/) print $1,$9} ' Access.log|sort|uniq–c|sort–nr | awk ' {if ($1>20) print $ '

#11用 the ciphertext portion of the/etc/shadow file replaces the "x" position in the/etc/passwd, generating a new/tmp/passwd file.

awk ' begin{ofs=fs= ': '} nr==fnr{a[$1]=$2}nr>fnr{$2=a[$1];p rint >> "/tmp/passwd"} '/etc/shadow/etc/passwd

#12, awk count Server Status connections:

Netstat-an | awk '/tcp/{s[$NF]++} END {for (a in s) {print A,s[a]}} ' Netstat-an | awk '/tcp/{print $NF} ' | Sort | Uniq-c

#13, get the IP address of the eth0

Ifconfig eth0|grep "Bcast" |awk ' {print $} ' | Awk-f: ' {print $} '

#14, add output at the beginning and end of the output

#在所有行添加列名name, Shell, add "Blue,/bin/nosh" to the last line

Awk-f ': ' BEGIN {print ' Name,shell '} {print $ '---' $7} END {print ' Blue,/bin/nosh '} '/etc/passwd

#15, find out which system users are not allowed to log on

Awk-f: '/nologin/{print $ '/etc/passwd

#16, identify the user of the root group

Awk-f: ' $4 ==0 {print ' The user of group root: ' $ '/etc/passwd

This article is from the "Mo Jing" blog, reproduced please contact the author!

Some uses of Shell awk