Replace words

To replace the word old-word with new-word in all .txt files we can use sed:

_$: sed -i 's/old-word/new-word/g' *.txt


Change the word .yaml for .yml in the main.yml file:

_$: sed -i 's/.yaml/.yml/g' main.yml

Change the word DBPASS for DB_PASSWORD in all .php files:

_$: sed -i 's/DBPASS/DB_PASSWORD/g' *.php

Change the CRLF to LF:

_$: sed -i 's/\r//g' file.log

Rename files

To mass rename files we can use the rename command. It is highly advised to first run it with the -n flag turned on.


Remove the .txt extension from those files:

_$: rename 's/\.txt$//' *.txt

Change the .yaml extension to .yml

_$: rename 's/\.yaml$/\.yml/' *.yaml

Change the awstats.nginx.* files to awstats.web1.* in the current directory:

_$: rename 's/awstats\.nginx\./awstats\.web1\./' ./*

Change the awstats*.nginx.* files to awstats*.web1.* in the current directory:

_$: rename 's/awstats(.*)\.nginx/awstats$1\.web1/g' ./*

Search a word in files

We will use find and grep for this task.

Example: Search for word in all .py files:

_$: find . -name "*.py" -type f -exec grep "word" {} \; > output.txt
_$: find . -name "*.py" -type f -exec grep "word" {} +