使用awk或sed或cut過濾文本文件？

Question

我正在嘗試解決此問題。

$ cat test.txt  
server1
ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com
Search
ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web
ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web
ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2
ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb
ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
ec2dd
ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2
ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb
ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com

我需要這樣的輸出：

$ cat test.txt
server1:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com  
Search:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com  
Web:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com  
Web:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com  
server2:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com  
loaddb:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com  
ec2dd:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com  
server2:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com  
loaddb:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com

Answer 1

使用sed ：

$ sed 'N;s/\n/:/' test.txt
server1:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com
Search:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2:ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
ec2dd:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2:ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com 

此方法使用兩個sed命令：

• N從文件中讀取第二行，並將其添加到模式空間。 這樣，模式空間中始終具有連續的兩行。

• s/\\n/:/從模式空間的兩行之間刪除換行符，並用冒號代替。

使用awk ：

$ awk 'NR%2==1{name=$1;next} {print name ":" $0;}' test.txt
server1:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com
Search:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2:ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
ec2dd:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2:ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com 

筆記：

• NR%2==1{name=$1;next}

  這將讀取第一行和所有后續的奇數行，並將第一個字段分配給變量name 。 然后，它跳過其余命令，並跳轉到next行重新開始。

• print name ":" $0

  在偶數行上，這將打印名稱，冒號和當前行。

使用純殼

while read name; read line
do
        printf "%s:%s\n" "$name" "$line"
done <test.txt

在這里，從text.txt中將一行讀入變量name然后將另一行讀入變量line 。 然后將這兩個標記之間用冒號打印。

Answer 2

您可以簡單地使用paste命令，

paste -d: - - < file

通過Perl，

perl -pe 's/\n/:/g if $.%2==1' file

$. Perl中的NR與awk中的NR相似。 因此，它僅采用奇數行並將換行符替換為:僅在特定行上。

Answer 3

這個awk可以做到，但是如果您不完全了解getline ，請小心。

awk '{a=$1;getline;print a":"$1}' file
server1:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com
Search:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2:ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
ec2dd:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2:ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com

這是一種更好的方法：

awk 'ORS=NR%2?":":RS' file
server1:ec2-xx.xx.xx.xxus-west-2.compute.amazonaws.com
Search:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
Web:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2:ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
ec2dd:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
server2:ec2-xx.xx-xx-xx.us-west-2.compute.amazonaws.com
loaddb:ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com