Useful Bash Commands

Simple list of bash commnads with short explanation

Goal: create a file name myfile.txt

touch myfile.txt

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Goal: read a file name myfile.txt

cat myfile.txt

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Goal: copy a myfile.txt file from folder1 to folder2 for this we expect both folder1 and folder2 to be in the same parent folder

cp ./folder1/myfile.txt ./folder2/myfile.txt

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Goal: create a parent and child folder then create a text file in new folder structure

mkdir -p parent/child/ | touch parent/child/mystuff.txt

-p is the imporant part, without is you will get an error that the parent folder does not exist when it trys to create the child folder

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Goal: see a complete list of all the commands that have been run

history

this one I like to use with connections to servers that I might have accessed in the past, but do not remember the ssh connection string, and did not create a server alias. so say the IP addres is 10.5.5.53 I could looks through my history to find the ssh connection like this

history | grep  10.5.5.53

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Goal: find a file by name somewhere and display it’s contents

find --name example.html -exec cat {} \;

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Goal: get the last entires in a log file AND automatically refresh the terminal when new log entries appear

tail -f /var/log/nginx/error_log

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Goal: find a string in a file and then show 10 line before and 20 lines after

cat someFile.txt | grep -B10 -A20 some_string_to_find

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