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alanmynah
alanmynah

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Learn Command Line

#commandline #bash #scripting

This is a cheat-sheet to go along with the stream I did on Scrimba YouTube channel about command line.

Command Line notes

Where am i? What's here? How do i console.log? 

pwd ls echo 'hello Scrimba!'
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CRU(M)D 

# create mkdir cmd-session cd cmd-session touch script.sh mkdir sub-folder # read ls sub-folder cat script.sh # move/update mv script.sh sub-folder/script.sh mv script.sh new-name-new-file.sh # delete rm script.sh rm -rf sub-folder
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Execute

Create a script.sh, example:

# touch script.sh, open it and write something like: echo "hello, running script!" echo "where am i?" pwd echo "ok, let's go somewhere else!" cd /code pwd echo "that's better"
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To execute a script:

./script.sh ### oh no, permission denied! what now?
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Permissions 

# see permissions ls -l # they are repeated, 3 times, for user (owner of the file), group of users, everyone else. # -rwx - read, write, execute # to change permissions chmod u+x ./script.sh
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Alias 

alias script='~/script.sh' # is this an alias? type script
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Getting help and Man pages 

node --help # -- is how you indicate a flag, -h is a shorthand, so node -h is the same.
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For linux's own utilities, --help wouldn't work, so they have man manual command.

man ls
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For a more visually pleasant man pages:
https://explainshell.com/

Bonus: Search 

grep 'echo' ./script.sh grep '<body>' ./ # grep: ./: Is a directory error, so you need to add recursive flag to search through directories grep -r '<body>' ./
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Top comments (2)

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bobbyiliev profile image
Bobby •

Great tips!

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alanmynah profile image
alanmynah •

Thanks a lot