Creating files and directories

Last updated on 2024-02-28 | Edit this page

Overview

Questions

  • How do I create, delete, copy, and move files and directories on my computer?
  • How can I identify the location of files on my computer?

Objectives

  • Create a directory hierarchy that matches a given diagram
  • Create empty files in the filesystem at a given location
  • Delete specified files and/or directories
  • Copy and move files and/or folders from and to a specified location

Working with files and folders

As well as navigating directories, we can interact with files on the command line: we can read them, open them, run them, and even edit them. In fact, there’s really no limit to what we can do in the shell, but even experienced shell users still switch to graphical user interfaces (GUIs) for many tasks, such as editing formatted text documents (Word or OpenOffice), browsing the web, converting sound files from one format to another, etc. But if we wanted to do this hundreds of music tracks, say then we could automate that conversion work by using shell commands.

Before getting started, we will use ls to list the contents of our current directory. Using ls periodically to view your options is useful to orient oneself.

BASH 

$ ls

Copy and moving files into subdirectories

Start with the following filesystem hierarchy:

/Users/jamie/data
    - chords.json

Assume your username is jamie. Reorder the following commands

  • cp recombined/chords.json ../chords-backup.json
  • cd ~/data
  • mv chords.json recombined/
  • mkdir recombined

so that when you execute the following commands, they return the output as shown:

BASH 

$ ls
recombined

$ ls recombined
chords.json
  • cd ~/data
  • cp recombined/chords.json ../chords-backup.json
  • mkdir recombined
  • mv chords.json recombined/

Try another way

Can you think of another way to achieve the same effect?

There are lots.

Using history

Use the history command to see a list of all the commands you’ve entered during the current session. You can also use Ctrl + r to do a reverse lookup. Press Ctrl + r, then start typing any part of the command you’re looking for. The past command will autocomplete. Press enter to run the command again, or press the arrow keys to start editing the command. If multiple past commands contain the text you input, you can Ctrl + r repeatedly to cycle through them. If you can’t find what you’re looking for in the reverse lookup, use Ctrl + c to return to the prompt. If you want to save your history, maybe to extract some commands from which to build a script later on, you can do that with history > history.txt. This will output all history to a text file called history.txt that you can later edit. To recall a command from history, enter history. Note the command number, e.g. 2045. Recall the command by entering !2045. This will execute the command.

Key Points

  • cp copies data from one location (a source) to another (a target)
  • cp takes its source(s) and target as arguments
  • mkdir can be used to create directories
  • mv can be used to move data from one location to another, and is similar to copying followed by deletion
  • cp and mv modify your files, and can lead to data loss