


This article mainly introduces the use of sed command and awk command in Linux. It has certain reference value. Friends in need can refer to it. I hope it can help everyone.
1. sed command: Without redirection, the content in the source file will not be actually modified
Query statement
①sed -n '/sbin/p' passwd
means to query all the lines with sbin characters in the passwd file and print them out. The two /s represent regular expressions. -n and /p are the parameters of the command. Need to be used in combination
②sed -n 'xp' passwd
x is a number, which means printing out the data of line x in the passwd file
New Add statement
①sed '1a This is the content added after the first line' passwd
where a means to add content, and the number 1 means which line it is, above The meaning of the statement means to add content after the first line of the passwd file
②sed '1i This is the data inserted before the first line' passwd
where i means insert Data, the number 1 indicates which row, the above statement means to insert text content before the first row
3, sed '1c hello world' passwd
c Indicates replacement. The statement means to replace the first line in the password file with hello world
4, sed 's/false/true/' passwd
means to replace Replace the false characters in the passwd file with true characters
Delete the statement
①sed '/postgres/d' passwd
Delete the regular expression in the passwd file Formula to match all lines of postgres
2, sed '2d' passwd
Delete the second line in the passwd file
## Summary
The above is the entire content of this article about the use of sed command and awk command in Linux. I hope it will be helpful to everyone. Interested friends can continue to refer to other related topics on this site. If there are any shortcomings, please leave a message to point out. Thank you friends for supporting this site! Related recommendations:Detailed introduction to the sed command
Detailed sharing of sample code for the sed command in Linux
php cannot implement the sed command in the shell script-
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