$ sudo apt update
$ sudo apt -f install
$ sudo apt full-upgrade
$ sudo apt install gimp
sudo apt updatesudo apt -f installsudo apt full-upgradesudo apt install gimpgimp, as one can guess.Renaming a specific file
$ rename ....
Append .txt to all files
$ rename -a ".txt" *
$ ls
my-file-1.txt my-file-2.txt my-file-3.txt my-file-4.txtPrepend my- to all files
$ rename -A "my-" *
$ ls
my-file-1 my-file-2 my-file-3 my-file-4Substitute — with _ in all occurrences using the -S option
$ rename -S "-" "_" *
my_file_1.txt my_file_2.txt my_file_3.txt my_file_4.txtFind all files recursively using the find command in the current directory
$ find . -name "foo*"
Delete Directory
$ sudo rm -r /path/to/folderNameNote: The parameter letters of -f, -r, -v can be used together (-rf no spaces) or separately:
-f to ignore non-existent files, never prompt-r to remove directories and their contents recursively-v to explain what is being doneAnother simplified method of deleting a diretory
$ rmdir /path/to/folderNameCopying example.txt into Documents
$ cp example.txt ~/Documents
Copy into a new file name (similar to mv)
$ cp example.txt ~/Documents/file.txt
Copy a folder (--verbose shows details and is not needed)
cp -r --verbose Documents NewDocumentsMoving a file
$ mv example.txt file.txt
$ mv example.txt ~/Documents/file.txtTo prevent a file from being overwritten without warning use --interactive (or -i for short)
$ mv -i example.txt ~/Documents
Find machine IP Address
$ ifconfig -aList active applications and their listening interface and port number
$ sudo netstat -tlnpReturns all the elements of a JSON
$ curl https://jsonplaceholder.typicode.com/users | jq '.[]'Returns the first element of a JSON
$ curl https://jsonplaceholder.typicode.com/users | jq '.[0]'
Returns only the name (in company object) property of the first element
$ curl https://jsonplaceholder.typicode.com/users | jq '.[0] | {name: .company.name}'Returns only the name AND lat (different objects) properties of the first element
$ curl https://jsonplaceholder.typicode.com/users | jq '.[0] | {name: .company.name, lat: .address.geo.lat}'