Computation for Linguists

Learning the Command Line: Files and Directories

Dr. Andrew M. Byrd

2025-09-22

Plan for the Day

• Review
• Learning the Terminal
• Making and Renaming Files & Folders
• A Couple More Tricks

Review

Review: So far, you have learned about…

• File structure & dependencies

  • In LaTeX, you had to make sure images, .bib files, and style files were in the right folder so the document would compile.
  • In HTML/CSS, you linked CSS files and images using relative paths.

Review: So far, you have learned about…

• Commands as instructions
  • LaTeX commands (\section{}, \usepackage{})
  • CSS rules (color: blue;) are small, precise instructions.
  • You have learned about proper syntax, arguments, flags/options, and order of operations.

Review: So far, you have learned about…

• Reproducibility & automation
  • In LaTeX, you built a reproducible doc (compile again, get the same result).
  • In HTML/CSS, you built a reusable template within CSS files.

This week:

You may be thinking:

• Nooooooooooooooooooooooooooooo!
• I’m still scarred from installing GitHub.
• Please let’s not go back there.

But:

• It’s important to understand how the basics work.
  • Where do files live?
  • How do we navigate between them?
• And the above concepts - file structure & dependencies, commands, and reproducibility - will be present here, too.

Learning the Terminal

Why start in the terminal?

• Python always runs inside a folder (your working directory).
• If you can move, list, and fetch files here, this will make it easier to understand how to access files in Python later.
• Same skills for Git and other computational environments, like:
  • servers and clients
  • clusters (computers set up to work together)

Why start in the terminal?

• While this isn’t the case for me, I’ve been assured by various linguists that understanding how the Terminal works is crucial for conducting certain types of research, particularly in Phonetics

Navigating the Terminal

• We’ll be working within the Terminal in RStudio

You should have the setting “New terminals open with:

Navigating the Terminal

• Let’s start with the first command

pwd         # short for "print working directory"

Navigating the Terminal

• You can also look to see what’s in the current directory

ls           # short for "listing files"

Navigating the Terminal

• Most commands have options

ls -l        # details (permissions, size, dates)
ls -a        # include hidden files (like .git)

Navigating the Terminal

cd          # short for "change directory"

• You need to specify which directory to change into
• For now, use:

cd ~         

Navigating the Terminal

• Type:

ls        

• Find a directory (dir_name) within it, and type (replacing dir_name with the actual directory name):

cd dir_name        

• This should move you “up” into the directory. Verify this is the case with ls.

Navigating the Terminal

cd projects           # into a folder
cd ..                 # up one
cd ~                  # to home
cd ~/Desktop          # absolute path to Desktop\
cd "My Folder"        # if there are any spaces in your named folder

Activity

1. Type cd ~, to bring you to your home directory
2. Using pwd and ls as your guide, navigate your way into your LIN_301 folder

Making and Renaming Files & Folders

mkdir

• You should now be in your LIN_301 folder in the Terminal Prompt
• Look in the right bottom corner panel of RStudio, what do you see?
• Type the following code:

mkdir test_folder     # short for "make directory"

• Now look in the right corner - did anything change?

rmdir

• Now type the following code

rmdir test_folder    # short for "remove directory"

• Look in the right corner of RStudio - did anything change?

touch

• Now type the following code:

mkdir test_bolder
touch test_doc.txt

• Look in the right corner of RStudio - did anything change?
• What does touch do?

mv

• We want to place our new txt file in the folder, so let’s run this code:

mv test_doc.txt test_bolder/    # short for "move"

mv

• Ah crap, I misspelled test_bolder, let’s run this code:

mv test_bolder test_folder    # how you rename in bash

Activity

• Within your LIN_301 repo:
  • Create a file called activity.txt
  • Create the following folders: folder_1 > folder_2 > folder_3
  • Move activity.txt inside folder_3
• You can only use the Terminal in RStudio!
  • Use pwd and ls as your guide

A Couple More Tricks

curl

• We all know how to download things from the Internet, but what about using the Terminal?
• Type this code:

curl -o term_comm.txt https://winjapati.github.io/301_Fall_2025/3_command_line/12_term_comm.txt#

• This is a useful list of Terminal commands
• Move this file into folder_1

rm -r

• Let’s learn one more bash command

rm -r folder_1

• What happens?

You bastard!

• Don’t worry! Type the following code:

touch script.sh 

Bringing it Back

• Now copy and paste (use right click) into the Terminal:

cat > script.sh <<'EOF'     
#!/bin/bash                 
echo "This is my first script."
curl -o term_comm.txt https://winjapati.github.io/301_Fall_2025/3_command_line/12_term_comm.txt#
mkdir folder_1
mv term_comm.txt folder_1
echo term_comm.txt

• Then type:

EOF

• Look inside script.sh, what did you do?

OMG

• Type:

source script.sh