Cheatsheet
Contents
Cheatsheet¶
Patterns and examples of how to accomplish frequent tasks. We will build up this section together over the course of the semester.
Basic Bash file operations¶
Move one folder up:
cd ..
Move at the top of your directory:
cd
Move to the specified directory:
cd directory
Create a file:
touch file_name.ext
Text editor:
nano file_name.ext
Display content:
cat file_name.ext
Create a new folder:
mkdir new_folder_name
Move a file:
mv file_name.ext folder_name_file_is_going_moved_to
Move multiple files:
mv file_name1.ext file_name2.ext file_name3.ext folder_name_files_are_going_moved_to
List files in the current directory:
ls
ls -hl //displays rw-r-r
ls -G - //folders are colorized
ls -hlG //displays rw-r-r and folders are colorized
Show your currect directory:
pwd
Remove a file:
rm file_name.ext
Copy a file:
cp file_name.ext copied_file_name.ext
Note
In every command you can add your directory/ location (ex. docs/file_name.ext).
“.” dot symbolizes our current location and “…” two dots, one level up in the directory tree.
“” represents any number of unknown characters; creates a pattern (ex. rm pyt.py removes all files that start on ‘pyt’ and end with extension py).
Delete an empty directory:
rmdir directory
Since you can’t delete a directory with files in it you need to recursively delete the folder and its contents. The -R is a recursive declaration which tells the terminal to delete the folder, the files within the folder, subfolders, files in the subfolder etc. Source
Delete everything in a directory without confirmation:
rm -R directory
The -i is a flag that prompts you if you want to remove each separate file in the directory.
Delete everything in a directory with confirmation:
rm -iR directory
List the contents of the directory:
ls
Git status displays the current state of the repository relative to the working directory. Shows the differences between the index file and the current directory.
git status
Redirect Output:
to overwrite an existing file or a create a new file with the given file name:
echo "send output to file.txt" > file.txt
to append the output to already existing file or create a new file with the given file name:
echo "append output to file.txt >> file.txt
Git log allows you to see all of the hashes of your previous commits in your branch:
git log
Wildcard / Kleene star¶
The wildcard character in bash * works by expanding in place to separate arguments that match whatever pattern you’re writing.
Example, given a directory stuff/:
stuff/
a.py
b.py
c.py
other.txt
another.md
nested_folder/
If we were to run ls *.py while in the stuff/ directory, the command actually run by the computer is ls a.py b.py c.py. This also works for commands like mv. I.e. mv *.py nested_folder/ runs mv a.py b.py c.py nested_folder/
This is video explains what a half-adder is