Linux basic operations to modify files

Each line in the loop A file matches the B file, if the same, write this line to the C file

for i in `cat all.txt` ; do grep -n "$i" zhongxin2.txt >> zhongxin2_result.txt ; done

Find the payId in the number of matching lines in the log

for i in `ls -1 *.txt`

do
awk '{print "999,"$0}' $i > sqldir/$i.csv

done

awk -F specifies to split the string

awk -F 'split string' 'print expression' file a > file b

gawk -F ',' '{print "999,"$1}' 1.txt > b.txt

Operation 1.txt file is separated by comma and print 999, + the first split string, the result is stored in b.txt

sed -i 's/http:/https:/g' *.txt.csv

for i in `ls -1 *.csv |sort -n | head -n 35`
do
echo $i
mysql -p'xxxxxx' DPEmidas -e "load data infile '/data/dataMigration/sqldir/$i' ignore into table CDKEY fields terminated by ',' (ActivityId,Code);" 2>/dev/null
done

wc -l code.txt

split -l 1000000 -d code.txt url/code_

wc -l *

cp * ../code/

sed -i 's/https:\/\/dpurl.cn\/s\/an928?p=//g' *

Change the file suffix: for i in `ls -1`; do mv $i $i.txt ; done
ll
linux format to windows format: unix2dos *

[Switch] Linux awk command detailed

Original link: http://blog.chinaunix.net/uid-23302288-id-3785105.html

awk is a line processor : compared to the advantages of screen processing, there is no memory overflow or slow processing when processing large files, usually used to format text information

Awk processing process: process each line in turn, and then output

awk command form:

awk [-F|-f|-v] ‘BEGIN{} //{command1; command2} END{}’ file

[-F|-f|-v] Large parameter, -F specifies the separator, -f calls the script, -v defines the variable var=value

' ' reference code block

BEGIN initialization code block, before processing each line, initialize the code, mainly refer to global variables, set the FS separator

// match code block, can be a string or a regular expression

{} Command code block, containing one or more commands

; Multiple commands are separated by semicolons

END end code block, code block executed after each line is processed, mainly for final calculation or output of end summary information

Special points:

$0 means the entire current line

$1 the first field of each line

NF field quantity variable

NR record number per line, incrementing for multi-file records

FNR is similar to NR, but multi-file records are not incremented, and each file starts from 1

\t Tab character

\n newline

Delimiter is defined when FS BEGIN

The record separator entered by RS , the default is a newline (that is, the text is entered line by line)

~ matches, not an exact comparison compared to ==

!~ does not match, inexact comparison

== equals, must all be equal, exact comparison

!= 不等于，精确比较

&&　逻辑与

|| 逻辑或

+ 匹配时表示1个或1个以上

/[0-9][0-9]+/ 两个或两个以上数字

/[0-9][0-9]*/ 一个或一个以上数字

FILENAME 文件名

OFS 输出字段分隔符，默认也是空格，可以改为制表符等

ORS 输出的记录分隔符，默认为换行符,即处理结果也是一行一行输出到屏幕

-F'[:#/]' 定义三个分隔符

print & $0

print 是awk打印指定内容的主要命令

awk '{print}' /etc/passwd == awk '{print $0}' /etc/passwd

awk '{print " "}' /etc/passwd //不输出passwd的内容，而是输出相同个数的空行，进一步解释了awk是一行一行处理文本

awk '{print "a"}' /etc/passwd //输出相同个数的a行，一行只有一个a字母

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

awk -F: '{print $1; print $2}' /etc/passwd //将每一行的前二个字段，分行输出，进一步理解一行一行处理文本

awk -F: '{print $1,$3,$6}' OFS="\t" /etc/passwd //输出字段1,3,6，以制表符作为分隔符

-f指定脚本文件

awk -f script.awk file

BEGIN{

FS=":"

}

{print $1} //效果与awk -F":" '{print $1}'相同,只是分隔符使用FS在代码自身中指定

awk 'BEGIN{X=0} /^$/{ X+=1 } END{print "I find",X,"blank lines."}' test

I find 4 blank lines.

ls -l|awk 'BEGIN{sum=0} !/^d/{sum+=$5} END{print "total size is",sum}' //计算文件大小

total size is 17487

-F指定分隔符

$1 指指定分隔符后，第一个字段，$3第三个字段， \t是制表符

一个或多个连续的空格或制表符看做一个定界符，即多个空格看做一个空格

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

awk -F":" '{print $1 $3}' /etc/passwd //$1与$3相连输出，不分隔

awk -F":" '{print $1,$3}' /etc/passwd //多了一个逗号，$1与$3使用空格分隔

awk -F":" '{print $1 " " $3}' /etc/passwd //$1与$3之间手动添加空格分隔

awk -F":" '{print "Username:" $1 "\t\t Uid:" $3 }' /etc/passwd //自定义输出

awk -F: '{print NF}' /etc/passwd //显示每行有多少字段

awk -F: '{print $NF}' /etc/passwd //将每行第NF个字段的值打印出来

awk -F: 'NF==4 {print }' /etc/passwd //显示只有4个字段的行

awk -F: 'NF>2{print $0}' /etc/passwd //显示每行字段数量大于2的行

awk '{print NR,$0}' /etc/passwd //输出每行的行号

awk -F: '{print NR,NF,$NF,"\t",$0}' /etc/passwd //依次打印行号，字段数，最后字段值，制表符，每行内容

awk -F: 'NR==5{print}' /etc/passwd //显示第5行

awk -F: 'NR==5 || NR==6{print}' /etc/passwd //显示第5行和第6行

route -n|awk 'NR!=1{print}' //不显示第一行

//匹配代码块

//纯字符匹配 !//纯字符不匹配 ~//字段值匹配 !~//字段值不匹配 ~/a1|a2/字段值匹配a1或a2

awk '/mysql/' /etc/passwd

awk '/mysql/{print }' /etc/passwd

awk '/mysql/{print $0}' /etc/passwd //三条指令结果一样

awk '!/mysql/{print $0}' /etc/passwd //输出不匹配mysql的行

awk '/mysql|mail/{print}' /etc/passwd

awk '!/mysql|mail/{print}' /etc/passwd

awk -F: '/mail/,/mysql/{print}' /etc/passwd //区间匹配

awk '/[2][7][7]*/{print $0}' /etc/passwd //匹配包含27为数字开头的行，如27，277，2777...

awk -F: '$1~/mail/{print $1}' /etc/passwd //$1匹配指定内容才显示

awk -F: '{if($1~/mail/) print $1}' /etc/passwd //与上面相同

awk -F: '$1!~/mail/{print $1}' /etc/passwd //不匹配

awk -F: '$1!~/mail|mysql/{print $1}' /etc/passwd

IF语句

必须用在{}中，且比较内容用()扩起来

awk -F: '{if($1~/mail/) print $1}' /etc/passwd //简写

awk -F: '{if($1~/mail/) {print $1}}' /etc/passwd //全写

awk -F: '{if($1~/mail/) {print $1} else {print $2}}' /etc/passwd //if...else...

条件表达式

== != > >=

awk -F":" '$1=="mysql"{print $3}' /etc/passwd

awk -F":" '{if($1=="mysql") print $3}' /etc/passwd //与上面相同

awk -F":" '$1!="mysql"{print $3}' /etc/passwd //不等于

awk -F":" '$3>1000{print $3}' /etc/passwd //大于

awk -F":" '$3>=100{print $3}' /etc/passwd //大于等于

awk -F":" '$3<1{print $3}' /etc/passwd //小于

awk -F":" '$3<=1{print $3}' /etc/passwd //小于等于

逻辑运算符

&&　||

awk -F: '$1~/mail/ && $3>8 {print }' /etc/passwd //逻辑与，$1匹配mail，并且$3>8

awk -F: '{if($1~/mail/ && $3>8) print }' /etc/passwd

awk -F: '$1~/mail/ || $3>1000 {print }' /etc/passwd //逻辑或

awk -F: '{if($1~/mail/ || $3>1000) print }' /etc/passwd

数值运算

awk -F: '$3 > 100' /etc/passwd

awk -F: '$3 > 100 || $3 < 5' /etc/passwd

awk -F: '$3+$4 > 200' /etc/passwd

awk -F: '/mysql|mail/{print $3+10}' /etc/passwd //第三个字段加10打印

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

awk -F: '/mysql/{print $3*$4}' /etc/passwd //求乘积

awk '/MemFree/{print $2/1024}' /proc/meminfo //除法

awk '/MemFree/{print int($2/1024)}' /proc/meminfo //取整

输出分隔符OFS

awk '$6 ~ /FIN/ || NR==1 {print NR,$4,$5,$6}' OFS="\t" netstat.txt

awk '$6 ~ /WAIT/ || NR==1 {print NR,$4,$5,$6}' OFS="\t" netstat.txt

//输出字段6匹配WAIT的行，其中输出每行行号，字段4，5,6，并使用制表符分割字段

输出处理结果到文件

①在命令代码块中直接输出 route -n|awk 'NR!=1{print > "./fs"}'

②使用重定向进行输出 route -n|awk 'NR!=1{print}' > ./fs

格式化输出

netstat -anp|awk '{printf "%-8s %-8s %-10s\n",$1,$2,$3}'

printf表示格式输出

%格式化输出分隔符

-8长度为8个字符

s表示字符串类型

打印每行前三个字段，指定第一个字段输出字符串类型(长度为8)，第二个字段输出字符串类型(长度为8),

第三个字段输出字符串类型(长度为10)

netstat -anp|awk '$6=="LISTEN" || NR==1 {printf "%-10s %-10s %-10s \n",$1,$2,$3}'

netstat -anp|awk '$6=="LISTEN" || NR==1 {printf "%-3s %-10s %-10s %-10s \n",NR,$1,$2,$3}'

IF语句

awk -F: '{if($3>100) print "large"; else print "small"}' /etc/passwd

small

large

small

awk -F: 'BEGIN{A=0;B=0} {if($3>100) {A++; print "large"} else {B++; print "small"}} END{print A,"\t",B}' /etc/passwd

//ID大于100,A加1，否则B加1

awk -F: '{if($3<100) next; else print}' /etc/passwd //小于100跳过，否则显示

awk -F: 'BEGIN{i=1} {if(i<NF) print NR,NF,i++ }' /etc/passwd

awk -F: 'BEGIN{i=1} {if(i<NF) {print NR,NF} i++ }' /etc/passwd

另一种形式

awk -F: '{print ($3>100 ? "yes":"no")}' /etc/passwd

awk -F: '{print ($3>100 ? $3":\tyes":$3":\tno")}' /etc/passwd

while语句

awk -F: 'BEGIN{i=1} {while(i<NF) print NF,$i,i++}' /etc/passwd

7 root 1

7 x 2

7 0 3

7 0 4

7 root 5

7 /root 6

数组

netstat -anp|awk 'NR!=1{a[$6]++} END{for (i in a) print i,"\t",a[i]}'

netstat -anp|awk 'NR!=1{a[$6]++} END{for (i in a) printf "%-20s %-10s %-5s \n", i,"\t",a[i]}'

9523 1

9929 1

LISTEN 6

7903 1

3038/cupsd 1

7913 1

10837 1

9833 1

应用1

awk -F: '{print NF}' helloworld.sh //输出文件每行有多少字段

awk -F: '{print $1,$2,$3,$4,$5}' helloworld.sh //输出前5个字段

awk -F: '{print $1,$2,$3,$4,$5}' OFS='\t' helloworld.sh //输出前5个字段并使用制表符分隔输出

awk -F: '{print NR,$1,$2,$3,$4,$5}' OFS='\t' helloworld.sh //制表符分隔输出前5个字段，并打印行号

应用2

awk -F'[:#]' '{print NF}' helloworld.sh //指定多个分隔符: #，输出每行多少字段

awk -F'[:#]' '{print $1,$2,$3,$4,$5,$6,$7}' OFS='\t' helloworld.sh //制表符分隔输出多字段

应用3

awk -F'[:#/]' '{print NF}' helloworld.sh //指定三个分隔符，并输出每行字段数

awk -F'[:#/]' '{print $1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12}' helloworld.sh //制表符分隔输出多字段

应用4

计算/home目录下，普通文件的大小，使用KB作为单位

ls -l|awk 'BEGIN{sum=0} !/^d/{sum+=$5} END{print "total size is:",sum/1024,"KB"}'

ls -l|awk 'BEGIN{sum=0} !/^d/{sum+=$5} END{print "total size is:",int(sum/1024),"KB"}' //int是取整的意思

应用5

统计netstat -anp 状态为LISTEN和CONNECT的连接数量分别是多少

netstat -anp|awk '$6~/LISTEN|CONNECTED/{sum[$6]++} END{for (i in sum) printf "%-10s %-6s %-3s \n", i," ",sum[i]}'

应用6

统计/home目录下不同用户的普通文件的总数是多少？

ls -l|awk 'NR!=1 && !/^d/{sum[$3]++} END{for (i in sum) printf "%-6s %-5s %-3s \n",i," ",sum[i]}'

mysql 199

root 374

统计/home目录下不同用户的普通文件的大小总size是多少？

ls -l|awk 'NR!=1 && !/^d/{sum[$3]+=$5} END{for (i in sum) printf "%-6s %-5s %-3s %-2s \n",i," ",sum[i]/1024/1024,"MB"}'

应用7

输出成绩表

awk 'BEGIN{math=0;eng=0;com=0;printf "Lineno. Name No. Math English Computer Total\n";printf "------------------------------------------------------------\n"}{math+=$3; eng+=$4; com+=$5;printf "%-8s %-7s %-7s %-7s %-9s %-10s %-7s \n",NR,$1,$2,$3,$4,$5,$3+$4+$5} END{printf "------------------------------------------------------------\n";printf "%-24s %-7s %-9s %-20s \n","Total:",math,eng,com;printf "%-24s %-7s %-9s %-20s \n","Avg:",math/NR,eng/NR,com/NR}' test0

[root@localhost home]# cat test0

Marry 2143 78 84 77

Jack 2321 66 78 45

Tom 2122 48 77 71

Mike 2537 87 97 95

Bob 2415 40 57 62

awk手册
http://www.chinaunix.net/old_jh/7/16985.html

Linux basic operations to modify files

[Switch] Linux awk command detailed

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