Useful Linux commands

The one-stop shop for all your Linux command needs. Most commands listed will work on our machines, though that can vary based on installed packages and/or operating systems.

File and Directory Management

ls

Lists all files and directories

• ls -a - List all files, including hidden ones like .ssh, .bashrc, and so on.
• ls -l - Include extra file information like permissions, owner, groups, modified date, and more.
• ls -s - List size of files in blocks.
• ls -S - List by size, largest first.

cd

Used to change the directory.

• cd - When no path is specified, you will move to the user's home directory. As root, you will move to /root/. As your user, you will move to /eccs/home/<username>/.
• cd /path/to/file - When changing directories, if you're not in the immediate parent directory, you need to specify the full path. For example, if my current working directory is /etc, I can cd jupyterhub since it's within /etc. However, if my current working directory is /bin, I would have to specify the full path for /etc/jupyterhub.
• cd . and cd .. - The . and .. are used for adjacent movement. cd . "moves" you into the current directory, so basically no movement. cd .. moves you backwards one directory.
• cd - - The dash specification takes you to the previous working directory regardless of adjacency.

mv

Used to move and rename files.

• This command uses a mv /path/to/file /path/to/destination syntax. It follows the same rules as cd in that you need to specify the full path unless moving to the current working directory or an adjacent directory.
• To rename a file, you can "move" it into a new one. mv old.txt new.txt will put the contents of old.txt into the newly created new.txt. This action will delete old.txt. NOTE: This WILL overwrite the file if you move it into a preexisting one.
• mv -i - If you're worried about overwriting files, you can use the -i specification. This will prompt you for confirmation before overwriting.