02. Files Management

In the first lab you learned to move around Sway and to run your first commands in the terminal. Now it is time to work with files and directories. Everything you keep on a computer (documents, movies, programs, settings) is a file, stored somewhere in a big tree of directories. In this lab you will learn how to find your way in this tree, how to name any file with a path, and how to create, copy, move and delete files, first with commands and then with Yazi, a file manager that runs in the terminal.

The most important idea of this lab is the path. Take your time with it: every command that works with files, in this lab and in all the following ones, receives paths.

Objectives

Understand how files and directories are organized in Linux: one tree, starting from /
Write absolute and relative paths, and know what ., .. and ~ mean
Calculate the absolute path from the current directory and a relative path
Read the manual page of a command and understand its SYNOPSIS
Navigate with pwd, cd, ls and tree, and type less with TAB completion
Find files anywhere in a directory tree with find
Read text files with cat and nano, and find out the type of any file with file
Create, copy, move, rename and delete files and directories with mkdir, touch, nano, cp, mv, rm and rmdir
Work with names that contain spaces and other special characters
Install and use Yazi to manage files with a few keys, including tabs

Resources

Razvan Deaconescu, Razvan Rughinis, Mihai Carabas, Alexandru Radovici, Utilizarea Sistemelor de Operare, Printech 2021
- Chapter 2 - Utilizarea sistemului de fișiere, sections 2.1.2, 2.1.3, 2.3.1, 2.3.2, 2.3.4 and 2.3.5
Brian Ward, How LINUX Works, 3rd Edition, No Starch Press, 2021
- Chapter 2 - Basic Commands and Directory Hierarchy, sections 2.3, 2.4, 2.5.3, 2.5.5, 2.5.6, 2.12, 2.13 and 2.19
Yazi - Quick Start
Yazi - Installation
The lecture slides: 02. Files Management
The manual pages: man ls, man cp, man mv, man rm, man mkdir, man tree, man find, man file

The File System Tree

On Windows, every drive has its own tree: C:\, D:\, and so on. On Linux there is only one tree, and it starts from a single directory called the root, written /. Everything is somewhere below it: the programs, the settings, the other disks and your own files.

/
├── bin/          programs (ls, cp, mv, ...)
├── etc/          system wide settings
├── home/         the users' files
│   └── student/  your home directory, also called ~
│       ├── Downloads/
│       ├── Movies/
│       └── watchlist.txt
├── tmp/          temporary files, anyone can write here
└── usr/          installed software

Your own files live in your home directory, /home/student (use your own user name instead of student). Usually you can write only in your home directory and in /tmp.

tip

Names in Linux are case sensitive: Movies, movies and MOVIES are three different names. Windows and macOS (with its default settings) do not care about upper and lower case letters, Linux does.

Hidden Files

A file or a directory whose name starts with a . is hidden: ls, tree and the file managers do not show it, unless you ask them to. There is nothing secret about hidden files, Linux only hides them to keep the listings short. Most of them keep the settings of your programs, in your home directory:

/home/student
├── .bashrc       settings of the shell (hidden)
├── .config/      settings of most programs: Sway, Yazi, ... (hidden)
├── .local/       data of the programs, for example the trash (hidden)
├── Downloads/
└── Movies/

ls -a (all) also lists the hidden files, and so does find, without any option.
To hide a file, rename it so that its name starts with a .: mv notes.txt .notes.txt. To show it again, rename it back: mv .notes.txt notes.txt.

caution

Do not delete the hidden files of your home directory if you do not know what they are: you can lose the settings of your programs.

Paths

A path tells the operating system where a file or a directory is. It is the list of directories you walk through, separated by /, and at the end the name of the file.

The Current Directory

Every terminal (and every running program) has one current directory: the directory where it "is" right now. When you open a new terminal, the current directory is your home directory. The prompt shows it (~ means your home):

[student@fedora ~]$ pwd
/home/student

info

pwd (print working directory) prints the current directory as an absolute path.

Absolute Paths

An absolute path starts with /. It is the full address of a file, from the root down to the file, so it works the same no matter where you are:

/home/student/Movies/the_odyssey.mkv
/etc/hosts
/tmp

Think of the full postal address of a person: country, city, street, number, name. Anyone can use it.

Relative Paths

A relative path does not start with /. It starts from the current directory. If you are in /home/student, then:

Movies/the_odyssey.mkv      means   /home/student/Movies/the_odyssey.mkv
watchlist.txt               means   /home/student/watchlist.txt

A relative path is shorter, but it depends on where you are: the same relative path means another file when you are in another directory. Think of directions such as "the second door on the left": they are correct only from where you are standing.

`.` and `..`

Every directory has two hidden entries:

Name	Means
`.`	the directory itself (the current directory)
`..`	the parent directory, one level up

They can be used anywhere in a path, and .. can be repeated to go up several levels. If you are in /home/student/Movies:

/
└── home
    ├── student
    │   ├── Movies            <-- .      (you are here)
    │   │   └── the_odyssey.mkv
    │   ├── Downloads
    │   │   └── supergirl.mp4
    │   └── watchlist.txt
    └── bob
        └── notes.txt

Relative path	Walk	Absolute path
`./the_odyssey.mkv`	stay in `Movies`, open the file	`/home/student/Movies/the_odyssey.mkv`
`../watchlist.txt`	up to `student`, open the file	`/home/student/watchlist.txt`
`../Downloads/supergirl.mp4`	up to `student`, down into `Downloads`	`/home/student/Downloads/supergirl.mp4`
`../../bob/notes.txt`	up to `student`, up to `home`, down into `bob`	`/home/bob/notes.txt`

tip

The root has no parent: /.. is still /.

From Relative to Absolute

This is how the operating system turns a relative path into an absolute one:

join the current directory, a / and the relative path;
from left to right, drop every .;
from left to right, every .. removes itself and the directory that is still left before it.

For example, from /home/student/Movies the path ../Downloads/./../../bob/notes.txt becomes:

/home/student/Movies/../Downloads/./../../bob/notes.txt      1. join
/home/student/Movies/../Downloads/../../bob/notes.txt        2. drop the .
/home/student/Downloads/../../bob/notes.txt                  3. Movies/.. cancel each other
/home/student/../bob/notes.txt                               3. Downloads/.. cancel each other
/home/bob/notes.txt                                          3. student/.. cancel each other

caution

A .. does not always cancel its neighbor: it removes the last directory still left before it. In the example above, the last .. removed student, which was far away from it in the original path.

You can check your calculation with the realpath command, which prints the absolute path of any path:

[student@fedora Movies]$ realpath ../Downloads/./../../bob/notes.txt
/home/bob/notes.txt

The Home Directory: `~`

In the terminal, ~ is replaced with the path of your home directory, so ~/Movies is /home/student/Movies, from any directory. Paths that start with ~ behave like absolute paths.

info

~ is a feature of the shell (the program that reads your commands). It does not work in every program: for example, Windows and most graphical applications do not understand it.

Every File is a Path

When a command expects a file or a directory, you can give it any path to it: a name, a relative path, an absolute path or a path with ~. From /home/student/Movies, all these commands print the same file:

$ cat ../watchlist.txt
$ cat /home/student/watchlist.txt
$ cat ~/watchlist.txt
$ cat ../../student/Downloads/../watchlist.txt

tip

You can also mix relative and absolute paths in the same command: cp ../watchlist.txt /tmp/.

Reading the Manual

Every command has a manual page: man ls, man cp, and so on. The page opens in a viewer with its own keys:

Key	What it does
`↑` / `↓`	Scrolls one line up / down
`Page Down` or `Space`	Scrolls one page down
`Page Up` or `b`	Scrolls one page up
`g` / `G`	Jumps to the beginning / the end of the page
`/` `word` `Enter`	Searches for `word`, see Searching in a Manual Page
`n` / `N`	Jumps to the next / previous match of the search
`h`	Shows the help, with all the keys
`q`	Quits

A manual page has several parts: NAME (what the command does, in one line), SYNOPSIS (how to call it), DESCRIPTION (what it does and all its options, one after another) and, at the end, SEE ALSO (related commands). The most useful part of a manual page is the SYNOPSIS: it shows how to call the command.

SYNOPSIS
       cp [OPTION]... SOURCE DEST
       cp [OPTION]... SOURCE... DIRECTORY

Notation	Meaning
`[ ]`	optional: this may or may not be present
`...`	can repeat: there may be more than one of these
`SOURCE`, `DEST`, `FILE`, `DIRECTORY`	a path (relative or absolute)
`-r`	a short option: one dash and a single letter
`--recursive`	a long option: two dashes and a full word, often the same as a short one

Searching in a Manual Page

A manual page is long: man ls has more than 200 lines. Do not read it from the top, search in it:

Key	What it does
`/` `word` `Enter`	Searches forward for `word` and jumps to the first line that contains it
`n`	Jumps to the next match
`N`	Jumps to the previous match
`?` `word` `Enter`	Searches backward, towards the beginning of the page

When you search, man highlights every match on the screen. The search is case sensitive: /Size does not find size.

For example, say you want ls to list the files in reverse order, but you do not know the option:

Run man ls.
Type /, then reverse, and press Enter. The page jumps to the first line that contains reverse:
```
       -r, --reverse
              reverse order while sorting
```
This is what you were looking for: the option is -r (or the long one, --reverse). If the first match is not what you need, press n until you find it.
Press q and try it: ls -r.

How to search well:

Search for what you want to do, not for the option, since you do not know it yet: size, hidden, reverse, directories, sort, time. The manual is in English, so search for English words.
Try other words if you find nothing: size, then human, then bytes.
Read the lines around every match, a word can appear in many options. Press n to go to the next one.
Jump to an option you already know: in the manual, an option starts its line, after a few spaces. To jump to the description of -l, search for ^ *-l: ^ means "the start of the line" and * means "any number of spaces". Searching only for -l also stops at every place where -l is just mentioned.

caution

Always read the manual before searching online or asking an AI. The manual on your computer is written for the version installed on your computer. An answer found online might be for another version, or simply wrong.

tip

Most commands also print a short summary of their options with --help, for example ls --help.

Working in the Terminal

`TAB` Completion

You do not have to type the full names of files, directories and commands. Type the first letters and press Tab:

if only one name starts with those letters, the shell writes the rest of it for you;
if several names start with them, nothing happens: press Tab a second time to see all of them, type one or two more letters and press Tab again.

You type	You press	The shell
`cd Mo`	`Tab`	completes it to `cd Movies/` (only `Movies` starts with `Mo`)
`cat wa`	`Tab`	completes it to `cat watchlist.txt`
`ls /etc/host`	`Tab` `Tab`	shows all the names that start with `host`, for example `host.conf hosts`
`ls /etc/she`	`Tab`	completes it to `ls /etc/shells`
`whoa`	`Tab`	completes the command to `whoami`
`ls --recu`	`Tab`	completes the option to `ls --recursive`

Completion works for every part of a path: cd /usTabshTabdoTab becomes cd /usr/share/doc/.

tip

Use Tab all the time: it is faster, and it does not make typing mistakes. If Tab completes nothing, even when you press it twice, then no name starts with what you typed: the path is wrong.

Editing a Command

You can fix a command before you press Enter, without typing it again:

Key	What it does
`←` / `→`	Moves the cursor one character left / right
`Ctrl`+`A`	Jumps to the beginning of the line
`Ctrl`+`E`	Jumps to the end of the line
`↑` / `↓`	Brings back the previous / next command you ran, so you can run it again or change it

For example, you typed ls ~/lab02/Gmaes/2026 and ls says No such file or directory: press ↑, move the cursor to the mistake with ←, fix it and press Enter. To add sudo or an option at the beginning of a long command, press Ctrl+A, then Ctrl+E to go back to the end.

Scrolling the Terminal

When a command prints more lines than fit on the screen, the first ones scroll off the top. Scroll the terminal back with the keyboard (or with the mouse wheel):

Key	What it does
`Shift`+`Page Up`	Scrolls the terminal one page up, towards older lines
`Shift`+`Page Down`	Scrolls the terminal one page down, back towards the prompt

This works in foot and in Ghostty. Typing anything brings the terminal back to the prompt.

Command	What it does
`pwd`	Prints the full path of the directory you're in ("print working directory")
`cat <file>`	Prints a file's entire contents to the screen
`cd <directory>`	Changes the current directory
`cd` or `cd ~`	Goes to your home directory
`cd -`	Goes to the previous directory (where you were before the last `cd`)
`ls`	Lists the current directory
`ls <path>`	if `<path>` is a directory, list the directory's contents / if `<path>` is a file, list the details of the file
`ls -a`	Also lists the hidden files (names that start with `.`)
`ls -l`	Long format listing: type, permissions, owner, size, last modified date
`tree`	Lists a directory and everything inside it, as a tree
`tree -L <number of levels>`	Only `<number of levels>` level deep

In the output of ls -l, the first letter is the type: d for a directory, - for a regular file. On Fedora, the permissions end with a .: it shows that the file has an SELinux label, you can ignore it for now. The first line, total, is the space used by the listed files, in blocks of 1 KB.

$ ls -l
total 32
drwxr-xr-x. 2 student student  4096 Sep 20 18:02 Downloads
drwxr-xr-x. 2 student student  4096 Sep 26 21:15 Movies
-rw-r--r--. 1 student student 21504 Sep 28 21:40 watchlist.txt

info

tree is not always installed. On Fedora install it with sudo dnf install tree, on Ubuntu with sudo apt install tree.

Examples

The examples use this home directory. The prompt shows the name of the current directory (~ is your home):

/home/student
├── .bashrc
├── Downloads
│   └── supergirl.mp4
├── Movies
│   └── the_odyssey.mkv
└── watchlist.txt

`pwd`

[student@fedora ~]$ pwd
/home/student
[student@fedora ~]$ cd Movies
[student@fedora Movies]$ pwd
/home/student/Movies

pwd printed the absolute path of the current directory: first the home directory, then, after cd Movies, the Movies directory inside it. The prompt shows only the last part of it (~, then Movies).

`cd`

[student@fedora ~]$ cd Movies
[student@fedora Movies]$ cd ../Downloads
[student@fedora Downloads]$ cd /etc
[student@fedora etc]$ cd -
/home/student/Downloads
[student@fedora Downloads]$ cd
[student@fedora ~]$

cd Movies went into Movies, using a relative path (from ~).
cd ../Downloads went up to /home/student, then down into Downloads.
cd /etc went to /etc, using an absolute path.
cd - went to the previous directory (/etc, where we were before the last cd), and printed its path.
cd alone went back to the home directory.

The Previous Directory: `cd -`

The shell remembers the directory you were in before the last cd. cd - goes there and prints its path:

[student@fedora ~]$ cd /etc
[student@fedora etc]$ cd ~/Movies
[student@fedora Movies]$ cd -
/etc
[student@fedora etc]$

caution

cd - is not a "back" button. A browser's Back button remembers every page you visited, and pressing it again takes you one more step into the past. The shell remembers only one directory, and cd - is itself a cd, so it replaces that directory with the one you just left. Pressing it again takes you forward, to where you came from.

For example, with three directories:

[student@fedora ~]$ cd /etc
[student@fedora etc]$ cd /tmp
[student@fedora tmp]$ cd ~/Movies
[student@fedora Movies]$ cd -
/tmp
[student@fedora tmp]$ cd -
/home/student/Movies
[student@fedora Movies]$ cd -
/tmp

After cd /etc, cd /tmp and cd ~/Movies, the previous directory is /tmp. /etc is already forgotten.
The first cd - went to /tmp, and the previous directory became Movies.
The second cd - did not go back to /etc. It went to Movies, and the previous directory became /tmp again.
From now on, cd - only switches between /tmp and Movies, like the "previous channel" button of a TV remote.

caution

Do not confuse cd - with cd .., either:

Command	Goes to	Pressed twice
`cd -`	the directory you were in before the last `cd`	you are back where you started
`cd ..`	the parent of the current directory, one level up the tree	you are two levels up
a browser's Back	the previous page, then the one before it, and so on	the shell has no such command

tip

cd - is very useful when you work in two directories at the same time, for example to copy files from one to the other.

`ls`

[student@fedora ~]$ ls
Downloads  Movies  watchlist.txt
[student@fedora ~]$ ls Movies
the_odyssey.mkv
[student@fedora ~]$ ls -a
.  ..  .bashrc  Downloads  Movies  watchlist.txt
[student@fedora ~]$ ls -l
total 32
drwxr-xr-x. 2 student student  4096 Sep 20 18:02 Downloads
drwxr-xr-x. 2 student student  4096 Sep 26 21:15 Movies
-rw-r--r--. 1 student student 21504 Sep 28 21:40 watchlist.txt
[student@fedora ~]$ ls -l watchlist.txt
-rw-r--r--. 1 student student 21504 Sep 28 21:40 watchlist.txt

ls listed the current directory. It does not show what is inside Movies.
ls Movies listed the Movies directory, without changing the current directory.
ls -a also listed the hidden entries: .bashrc, and . and .., which are in every directory.
ls -l listed one entry per line: the type (d directory, - file), the permissions, the owner, the size in bytes, the modification date, and the name.
ls -l watchlist.txt showed the details of only one file.

`tree`

[student@fedora ~]$ tree
.
├── Downloads
│   └── supergirl.mp4
├── Movies
│   └── the_odyssey.mkv
└── watchlist.txt

3 directories, 3 files
[student@fedora ~]$ tree -L 1
.
├── Downloads
├── Movies
└── watchlist.txt

3 directories, 1 file

tree showed the current directory and everything inside it, and counted the directories and files. The count includes the directory it started from, ., so there are 3 directories.
tree -L 1 stopped after the first level, like ls.

Finding Files: `find`

ls and tree show you what is in a directory. When you know the name of a file but not where it is, use find. It walks through a directory and through everything inside it, and prints the path of every entry that matches what you ask for.

find [directory]... [filter]...

Command	What it does
`find`	Prints every file and directory below the current directory
`find <directory>`	Lists everything inside `<directory>`, including subdirectories
`find <directory> -name '<name>'`	Only entries whose name is exactly `<name>`
`find <directory> -name '*.txt'`	Only the entries whose name ends with `.txt` (`*` means "any characters")
`find <directory> -type f`	Only the files
`find <directory> -type d`	Only the directories

tip

The filters can be combined, for example: find ~ -type f -name '*.txt' finds only the files whose name ends with .txt.

caution

Always put the name after -name between quotes ('*.txt'). Without quotes, the shell might replace *.txt with the names of the files in the current directory before find even starts.

Examples

Using the same home directory as in the Navigation examples:

[student@fedora ~]$ find Movies
Movies
Movies/the_odyssey.mkv
[student@fedora ~]$ find . -name '*.mp4'
./Downloads/supergirl.mp4
[student@fedora ~]$ find ~ -name '*.mp4'
/home/student/Downloads/supergirl.mp4
[student@fedora ~]$ cd Movies
[student@fedora Movies]$ find .. -name watchlist.txt
../watchlist.txt
[student@fedora Movies]$ find .. -type d
..
../Downloads
../Movies

find Movies printed the directory itself and everything inside it.
find . -name '*.mp4' searched the current directory (.) and everything below it, and found one file.
find ~ -name '*.mp4' found the same file, but printed an absolute path: find builds every path from the directory you give it. A relative start gives relative paths, an absolute start gives absolute paths.
From Movies, find .. -name watchlist.txt searched the parent directory and printed ../watchlist.txt, a relative path that works from Movies.
find .. -type d printed only the directories of .., including .. itself.

tip

find also finds the hidden files, without any option. The order of the results might be different on your computer.

info

When find searches a directory that you are not allowed to read (for example in /etc), it prints Permission denied for it and continues. You can ignore these messages.

Viewing Text Files: `cat` and `nano`

Most files in Linux, especially the settings in /etc, are text files: you can read them edit them using a text editor. There are two easy ways to look inside a text file: cat and nano.

`cat`

cat prints the whole content of one or more files in the terminal, and then the prompt comes back:

[student@fedora ~]$ cat /etc/machine-id
4c8e1f0a9d2b4e7f8a6c3b5d1e0f2a9c
[student@fedora ~]$ cat watchlist.txt
The Odyssey
Project Hail Mary
[student@fedora ~]$ cat /etc/machine-id watchlist.txt
4c8e1f0a9d2b4e7f8a6c3b5d1e0f2a9c
The Odyssey
Project Hail Mary
[student@fedora ~]$ cat notes.txt
[student@fedora ~]$

cat /etc/machine-id printed the content of the file: a number that is different on every installation of Linux, on a single line.
cat watchlist.txt printed a file from the current directory, using a relative path.
With several files, cat printed them one after another, with nothing in between.
notes.txt is empty, so cat printed nothing at all.

tip

cat is perfect for short files. For a long file, the beginning scrolls off the screen: scroll back with Shift+Page Up, or open the file with nano instead.

caution

Use cat only for text files. A program or a picture (for example cat /usr/bin/ls) prints strange symbols and can mess up the terminal. If this happens, type reset and press Enter (even if you cannot see what you type), or close the terminal and open a new one.

`nano`

nano is the text editor from Managing Files, but you can also use it only to read a file. It shows the file one screen at a time, and it is comfortable for long files:

[student@fedora ~]$ nano /etc/os-release

Key	Action
arrow keys, `Page Up`, `Page Down`	Scroll through the file
`Ctrl`+`W`	Search for a word
`Ctrl`+`X`	Exit (if you changed something, answer `N` to exit without saving)

To be sure that you do not change the file by mistake, open it in view mode, where nano does not let you type: nano -v /etc/os-release.

info

You can open the system files from /etc with nano and read them, but you cannot save them: nano says Permission denied. Exit without saving.

`cat` or `nano`?

Use	When
`cat`	The file is short, and you want to see it all at once, in the terminal
`nano`	The file is long, you want to scroll or search in it, or you want to edit it
`nano -v`	You prefer nano's interface but want read-only mode, so you can't change anything by accident

What Kind of File: `file`

The extension (.txt, .jpg, .mkv) is only part of the name: Linux does not need it, and it can lie. file looks inside a file and tells you what it really is (if file is missing, install it with sudo dnf install file):

[student@fedora ~]$ file watchlist.txt notes.txt Movies /etc/hosts
watchlist.txt: ASCII text
notes.txt:     empty
Movies:        directory
/etc/hosts:    ASCII text
[student@fedora ~]$ file /usr/bin/bash
/usr/bin/bash: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, ...
[student@fedora ~]$ cp /etc/hosts photo.jpg
[student@fedora ~]$ file photo.jpg
photo.jpg: ASCII text

watchlist.txt and /etc/hosts are text files: you can read them with cat or nano.
notes.txt is empty, and Movies is a directory.
/usr/bin/bash is an ELF executable, a program: do not cat it (the output above is shortened).
photo.jpg is called like a picture, but file shows that it is text: the extension does not change what is inside.

tip

Not sure if you can cat a file? Run file first: if the answer contains text, you can.

Managing Files

Command	What it does
`mkdir <directory>`	Creates a directory
`mkdir -p <path>`	Creates a directory and any missing parents (no error if it already exists)
`touch <file>`	Creates an empty file, or updates the "last modified" date of an existing one
`nano <file>`	Opens a text editor, the file is created when you save (`Ctrl`+`O` saves, `Ctrl`+`X` exits)
`cp <source> <destination>`	Copies a file
`cp <source>... <directory>`	Copies one or more files into a directory
`cp -r <directory> <destination>`	Copies a directory and everything inside it
`mv <source> <destination>`	Moves or renames a file or a directory
`mv <source>... <directory>`	Moves one or more files or directories into a directory
`rmdir <directory>`	Deletes an empty directory
`rm <file>`	Deletes a file
`rm -r <directory>`	Deletes a directory and everything inside it

info

There is no separate rename command: renaming is just moving a file to a new name in the same directory. For example, mv movie.mkv project_hail_mary.mkv renames movie.mkv to project_hail_mary.mkv.

caution

When you give cp or mv several sources, the last parameter must be a directory that already exists.

danger

There is no trash in the terminal: rm deletes files permanently, and rm -r deletes a whole directory with everything inside it. Read the command twice before pressing Enter, and never run rm -r with a path you do not fully understand.

Names with Spaces and Special Characters

The shell splits a command into words at every space. A name that contains a space becomes two parameters:

[student@fedora ~]$ touch shopping list.txt
[student@fedora ~]$ ls
Downloads  list.txt  Movies  shopping  watchlist.txt

touch received two names, shopping and list.txt, and created two files. To give a name with spaces as one parameter, put it between quotes, or put a \ before every space:

[student@fedora ~]$ rm shopping list.txt
[student@fedora ~]$ touch "shopping list.txt"
[student@fedora ~]$ ls -l shopping\ list.txt
-rw-r--r--. 1 student student 0 Sep 29 10:12 'shopping list.txt'
[student@fedora ~]$ rm 'shopping list.txt'

rm shopping list.txt deleted the two files created by mistake.
"shopping list.txt", 'shopping list.txt' and shopping\ list.txt are the same name. Tab completion adds the \ for you.
ls shows the name between quotes, so you can see that the space is part of the name.

Other characters also mean something to the shell: *, ?, $, !, &, ;, |, <, >, (, ), #, ', " and \. Put names that contain them between single quotes, for example touch 'rock & roll.txt' (between double quotes, $ and ! still have a special meaning). For a name with a ' in it, use double quotes: touch "it's mine.txt".

A name that starts with - looks like an option:

[student@fedora ~]$ touch -list.txt
touch: invalid option -- 'l'
Try 'touch --help' for more information.
[student@fedora ~]$ touch ./-list.txt
[student@fedora ~]$ rm ./-list.txt

note

Quotes would not help here, as the name still starts with -. Using ./-list.txt make is clear that it is a path. The ./-list.txt path is equivalent to the -list.txt, they point to the same file, just that and the first one it does not start with - and the command does not consider it an option.

tip

Name your own files using only letters, digits, ., _ and - (but not at the start): shopping_list.txt instead of shopping list.txt. They are much easier to use in the terminal.

Examples

The examples continue one after another, starting from the same home directory as in Navigation.

`mkdir`

[student@fedora ~]$ mkdir Series
[student@fedora ~]$ mkdir Series
mkdir: cannot create directory 'Series': File exists
[student@fedora ~]$ mkdir Series/2025/comedy
mkdir: cannot create directory 'Series/2025/comedy': No such file or directory
[student@fedora ~]$ mkdir -p Series/2025/comedy

The first mkdir Series created the empty directory /home/student/Series.
The second one failed: the directory already exists.
mkdir Series/2025/comedy failed, because Series/2025 does not exist yet, and mkdir creates only the last directory of the path.
mkdir -p created 2025 and then comedy inside it. With -p, it is not an error if a directory already exists.

`touch`

[student@fedora ~]$ touch notes.txt
[student@fedora ~]$ ls -l notes.txt
-rw-r--r--. 1 student student 0 Oct  1 10:15 notes.txt
[student@fedora ~]$ touch watchlist.txt
[student@fedora ~]$ ls -l watchlist.txt
-rw-r--r--. 1 student student 21504 Oct  1 10:16 watchlist.txt

touch notes.txt created a new, empty file: its size is 0.
touch watchlist.txt did not change the file, which already existed. It only changed its date to the current time.

`nano`

[student@fedora ~]$ nano notes.txt

nano opened notes.txt in a text editor, inside the terminal. Type some text, save it with Ctrl+O and Enter, and exit with Ctrl+X. If the file did not exist, nano creates it when you save. The bottom of the screen lists the keys: ^ means Ctrl.

`cp`

[student@fedora ~]$ cp watchlist.txt Series/
[student@fedora ~]$ cp watchlist.txt backup.txt
[student@fedora ~]$ cp Downloads/supergirl.mp4 Movies/the_odyssey.mkv Series/
[student@fedora ~]$ cp Movies Movies_backup
cp: -r not specified; omitting directory 'Movies'
[student@fedora ~]$ cp -r Movies Movies_backup

cp watchlist.txt Series/ copied the file into the Series directory, with the same name: Series/watchlist.txt.
cp watchlist.txt backup.txt made a copy with another name, in the same directory.
With several sources, cp copied all of them into the last parameter, the directory Series.
cp Movies Movies_backup refused to copy a directory.
cp -r copied the directory and everything inside it: Movies_backup/the_odyssey.mkv.

caution

If the destination directory already exists, cp -r Movies Movies_backup copies Movies inside it, as Movies_backup/Movies. Run the same command twice and look at the result with tree.

`mv`

[student@fedora ~]$ mv backup.txt old_watchlist.txt
[student@fedora ~]$ mv old_watchlist.txt Series/
[student@fedora ~]$ mv notes.txt Series/notes_2025.txt
[student@fedora ~]$ mv Series/watchlist.txt Series/supergirl.mp4 Downloads/

mv backup.txt old_watchlist.txt renamed the file: same directory, new name.
mv old_watchlist.txt Series/ moved the file into Series, with the same name.
mv notes.txt Series/notes_2025.txt moved the file and renamed it, in a single command.
With several sources, mv moved all of them into the last parameter, the directory Downloads. A file that already exists there with the same name is replaced, without any question.

`rmdir`

[student@fedora ~]$ rmdir Series/2025/comedy
[student@fedora ~]$ rmdir Series
rmdir: failed to remove 'Series': Directory not empty

rmdir Series/2025/comedy deleted the empty directory comedy.
rmdir Series failed: Series still has files and the directory 2025 inside it.

`rm`

[student@fedora ~]$ rm Series/notes_2025.txt
[student@fedora ~]$ rm Movies_backup
rm: cannot remove 'Movies_backup': Is a directory
[student@fedora ~]$ rm -r Movies_backup

rm Series/notes_2025.txt deleted the file, permanently.
rm Movies_backup refused to delete a directory.
rm -r Movies_backup deleted the directory and everything inside it.

Yazi

Yazi is a file manager that runs in the terminal. It shows your directories in three columns (the parent directory, the current directory and a preview) and does the work of cd, ls, mkdir, touch, cp, mv and rm with a few keys. It is fast and works well with Sway, because you never need the mouse.

Yazi

Installing Yazi on Fedora 44

Yazi is not in the official Fedora repositories. It is available from COPR, a service where Fedora users build extra packages. Enable the Yazi COPR repository and install the package:

sudo dnf copr enable lihaohong/yazi
sudo dnf install yazi

dnf asks you to confirm twice: once to enable the repository, once to install the packages. It also installs a few optional helpers that Yazi uses for previews. Check that it works:

yazi --version

caution

COPR repositories are unofficial: they are built by Fedora users, not by the Fedora project. The Yazi COPR repository is the one listed on the official Yazi installation page.

tip

If dnf says No such command: copr, install the plugin first with sudo dnf install dnf5-plugins, then run the commands again.

If the COPR repository does not have a package for your Fedora version yet, you can build Yazi yourself with Rust's package manager, cargo (it takes a few minutes):

sudo dnf install cargo
cargo install --force yazi-build

A Better Terminal for Yazi: Ghostty

Yazi works in any terminal, including foot, the default terminal of Sway. It looks better in a modern terminal such as Ghostty: Ghostty comes with the icons that Yazi uses for files and directories already built in, and Yazi can show previews of pictures inside it. Installing it is optional, but recommended.

Ghostty is not in the official Fedora repositories either. Install it from its COPR repository, the one listed on the official Ghostty installation page:

sudo dnf copr enable scottames/ghostty
sudo dnf install ghostty

Start it from the application launcher ($mod + d, type ghostty) or by running ghostty in a terminal, then run yazi inside it.

tip

To open Ghostty instead of foot with $mod + Enter, edit your Sway configuration file ~/.config/sway/config (see Modding Sway in lab 01): replace foot with ghostty in the line set $term foot (or in the line bindsym $mod+Return exec foot), then reload the configuration with $mod + Shift + c.

Using Yazi

Start it with yazi, or with a directory: yazi ~/Downloads. Quit with q. Press F1 or ~ for the help, which lists every key.

Key	Action	Like
`↑` `↓` (or `k` `j`)	Choose a file
`←` (or `h`)	Go to the parent directory	`cd ..`
`→` (or `l`)	Open the directory or the file	`cd`
`.`	Show / hide hidden files/directories	`ls -a`
`Space`	Select a file, for several files
`a`	Create a file; a name ending with `/` creates a directory	`touch`, `mkdir`
`r`	Rename	`mv`
`y` then `p`	Copy (yank), then paste	`cp`
`x` then `p`	Cut, then paste	`mv`
`d`	Move to the trash
`D`	Delete permanently	`rm`
`q`	Quit

info

The h j k l keys are the same as in Sway and vi (see Default Keybindings in lab 01).

caution

d moves files to the trash (~/.local/share/Trash), so they can be restored. D deletes them permanently, like rm.

Tabs

Yazi can keep several directories open, one in each tab. Every tab has its own current directory, so tabs make copying and moving between two directories easy.

Key	Action
`t` then `t`	Open a new tab, in the current directory
`1` ... `9`	Go to tab 1 ... 9
`[` `]`	Go to the previous / next tab
`Ctrl`+`c`	Close the current tab

To copy a file from ~/Downloads to ~/Movies: open ~/Downloads in tab 1, open a new tab with t t and go to ~/Movies in tab 2. Go back to tab 1 (1), choose the file and press y, go to tab 2 (2) and press p. Use x instead of y to move it.

Troubleshooting

Problem	Solution
`No such file or directory`	The path is wrong. Check the current directory with `pwd`, then check the path with `ls` or `realpath`. Remember that names are case sensitive
`cd` says `Not a directory`	The path points to a file, not a directory
`rmdir` says `Directory not empty`	`rmdir` deletes only empty directories. Delete what is inside first, or use `rm -r` (carefully)
`cp` says `-r not specified; omitting directory`	Add `-r` to copy a directory
`mv` or `cp` with several files says `target ... is not a directory`	The last parameter must be an existing directory
A name with spaces became several files	Put the name between quotes: `touch "shopping list.txt"`
`invalid option` for a file whose name starts with `-`	Use a path that does not start with `-`: `./-list.txt`
`Permission denied`	You are trying to write outside your home directory (and `/tmp`)
`yazi: command not found`	Yazi is not installed, see Installing Yazi on Fedora 44
Yazi shows strange symbols instead of icons	The terminal font has no icons. Everything still works; for icons, use Ghostty

Exercises

The exercises get harder as you go:

🧪 First Steps (exercises 1 - 34) goes once through everything in this lab, with easy exercises;
🏠 Going Further (exercises 35 - 53) has harder exercises;
📝 Challenges (exercises 54 - 62) has the hardest ones.

Do the exercises in order: each one uses the files left by the previous ones.

Some exercises ask for things that the lab does not show you, for example an option that is not in the tables above. Find it in the manual page of the command (man <command>), as explained in Searching in a Manual Page: search for words that describe what you need.

Keep two terminals side by side in Sway: one to run the commands, and one where you check the result with tree ~/lab02, ls or pwd after every exercise. In the paths below, replace student with your user name (run whoami to find it).

tip

If a command prints No such file or directory, the path is wrong: fix it and run the command again.

danger

Some exercises use real files of the operating system, outside your home directory. You can read most of them, but you cannot change them: they belong to the administrator (root). Never use sudo in these exercises. Without it, you cannot break anything; with it, a typing mistake in /etc can stop the computer from starting.

🧪 First Steps

info

Turn off the colors

For this lab, turn off the colors of ls and tree, so that you read the names and the type letters, not the colors, and your output looks like the one in the lab. Run these two commands in both terminals:

unset LS_COLORS
unalias ls

unset LS_COLORS turns off the colors of tree. On Fedora, ls is an alias for ls --color=auto, which has its own colors, so unalias ls turns them off too. The change lasts only until you close the terminal: to get the colors back, open a new terminal.

The practice tree:
1. Turn off the colors in both terminals, as explained above.
2. Run these commands to create the directories and files used in the exercises (copy them from the browser with Ctrl+C and paste them in the terminal with Ctrl+Shift+V):
```
mkdir -p ~/lab02/Photos ~/lab02/Games/2026/puzzles ~/lab02/Recipes
touch ~/lab02/books.txt ~/lab02/.secret
touch ~/lab02/Photos/cat.jpg ~/lab02/Photos/dog.jpg
touch ~/lab02/Games/chess.txt ~/lab02/Games/2026/puzzles/sudoku.txt
```
3. Install tree with sudo dnf install tree, if it is missing.
4. Run tree ~/lab02.
Check: you see this tree, without colors (the order of the lines might be a little different). Keep it open in the second terminal, you will need it in every exercise.
```
/home/student/lab02
├── books.txt
├── Games
│   ├── 2026
│   │   └── puzzles
│   │       └── sudoku.txt
│   └── chess.txt
├── Photos
│   ├── cat.jpg
│   └── dog.jpg
└── Recipes
```
→ The File System Tree · Navigation

tip

In exercises 2 - 8, run tree ~/lab02 in the second terminal before every command. Find on the tree the directory you are in, then follow the path of your command one name at a time, before you press Enter.

Where am I: Go to the Games directory using an absolute path, then into puzzles using a relative path, then back to ~/lab02 with a single cd that uses only ... Print the current directory after every step.

Check: you end up in /home/student/lab02. → The Current Directory · Absolute Paths
Absolute paths: From your home directory, show the details of cat.jpg, of sudoku.txt and of the Recipes directory itself (not what is inside it) with a single ls command and absolute paths. Look in man ls for the option that lists a directory itself (🔍 search for contents).

Check: you get exactly three lines, and the one of Recipes starts with d. → Absolute Paths · Reading the Manual
Relative paths: Do the same from ~/lab02, this time with relative paths. Then, from ~/lab02/Games, list the contents of Photos and of Recipes with a single ls and relative paths.

Check: the last command shows the two pictures and an empty Recipes. → Relative Paths
Going up and down: From ~/lab02/Games/2026/puzzles, show the details of books.txt and of dog.jpg with a single ls and relative paths. Then go to Photos with a single cd, and from there back to puzzles with another single cd, both with relative paths.

Check: you end up in /home/student/lab02/Games/2026/puzzles. → . and ..
Same file, many paths: From ~/lab02/Games/2026, show the details of books.txt with five different paths: an absolute one, one with ~, a relative one with only .., a relative one that goes through Photos, and a relative one that goes through both Photos and Recipes.

Check: all five commands print details about the same file. → Every File is a Path
Walk around: From your home directory, go to ~/lab02/Games/2026/puzzles with a single cd and an absolute path, then to ~/lab02/Recipes with a single cd and a relative path. Go back to puzzles with cd -, then home with the shortest command you can.

Check: cd - prints /home/student/lab02/Games/2026/puzzles, and you end up in /home/student. → Navigation
Back and forth: Go to /etc, then to ~/lab02/Photos. Using only cd -, jump back and forth between them twice. Then, from Photos, list /etc; jump to /etc with cd - and, from there, list Photos with a relative path.

Check: each cd - prints the directory it went to, and the last pwd prints /etc. → The Previous Directory: cd -
Listing: With a single ls command, list ~/lab02 and / so that you see the hidden file, can tell the files from the directories, and read the sizes in K / M (look in man ls, 🔍 search for sizes and read every match).

Check: you found .secret, and three directories. → Navigation · Reading the Manual
ls with a directory: From your home directory, list ~/lab02/Photos, ~/lab02/Games/2026/puzzles and / with a single ls, without changing the current directory.

Check: the output has three parts, one for each directory, and pwd still prints your home directory. → Every File is a Path
First look with tree: Show the tree of ~/lab02 only one level deep, then the whole tree with a / after the name of every directory (look in man tree, 🔍 search for Append).

Check: the first command shows Games, Photos and Recipes, but not chess.txt; in the second one, every directory ends with /. → Navigation · Reading the Manual
Type less: Press Tab after typing at most three letters of every name:
- go to /usr/share/doc;
- from there, show the details of ~/lab02/Games/2026/puzzles/sudoku.txt;
- find out which names in /etc start with pass, without running any command.
Check: pwd prints /usr/share/doc, ls -l shows sudoku.txt, and Tab Tab shows passwd and passwd-. → TAB Completion
Find by name: Find sudoku.txt twice: once searching from ~/lab02 with a relative start, once from your home directory with an absolute start.

Check: the first command prints ./Games/2026/puzzles/sudoku.txt and the second one /home/student/lab02/Games/2026/puzzles/sudoku.txt. → Finding Files
Find by extension: With a single find, find all the pictures (.jpg) in ~/lab02. Then all the .txt files.

Check: you get cat.jpg and dog.jpg, then books.txt, chess.txt and sudoku.txt. → Finding Files
Files or directories: Find only the directories in ~/lab02, then only the files.

Check: the directories are ., Games, 2026, puzzles, Photos and Recipes; the files include the hidden .secret. → Finding Files
Use what you found: From ~/lab02/Recipes, find chess.txt searching from .., then copy it into /tmp using the path that find printed.

Check: ls /tmp shows chess.txt. → Finding Files · Every File is a Path
Which Linux: Print the content of /etc/os-release with cat, with the number of every line in front of it (look in man cat, 🔍 search for number). Then open it in nano in view mode and search for VERSION with Ctrl+W.

Check: the lines NAME= and VERSION_ID= show Fedora and 44, and every line starts with its number. → Viewing Text Files · Reading the Manual
The identity of the computer: Print the content of /etc/machine-id, the number that identifies this installation of Linux. Then run hostnamectl, which prints information about the computer.

Check: the Machine ID line of hostnamectl shows the same number as the file. → Viewing Text Files
The users: Print /etc/passwd, the list of the users of the system, and find the line of your user (it starts with your user name. Copy the file to /tmp/users.txt and change the copy with nano.

Check: ls -l /etc/passwd /tmp/users.txt shows that only the copy was changed (look at the dates). → Viewing Text Files · Managing Files
The shells: Print /etc/shells, the list of the shells installed. Then show the details of /usr/bin/bash, the shell that runs in your terminal.

Check: /usr/bin/bash is in the list, and ls -l shows a file (first letter -) of about 1 MB. → Viewing Text Files · Every File is a Path
Programs are files: Show the details of the ls program itself, /usr/bin/ls. Then find every program in /usr/bin whose name starts with mk.

Check: mkdir is one of them. → Finding Files
What is this file: With a single file command, find out the type of /etc/hosts, /usr/bin/ls, /boot and ~/lab02/Photos/cat.jpg.

Check: /etc/hosts is text, /usr/bin/ls is an ELF executable, /boot is a directory, and cat.jpg is empty, even if its name ends with .jpg. → What Kind of File
Create files: Create an empty file groceries.txt and a file plan.txt with two lines of text in it. Then create soup.txt, pizza.txt and cake.txt in Recipes with a single command, without going into Recipes.

Check: ls -l shows size 0 for groceries.txt, but not for plan.txt; Recipes has the three new files. → Managing Files
Create directories: Create Albums/2024/summer and Albums/2025/winter with a single command.

Check: tree shows both directories. → Managing Files
Copy files: Copy books.txt into Albums. Copy cat.jpg and dog.jpg from Photos into Games with a single command, and make cp print the name of every file it copies (look in man cp, 🔍 search for explain). Copy dog.jpg into Albums/2025/winter under the name snow_dog.jpg. Finally, copy books.txt into Albums once more, but make cp ask you before it overwrites the file that is already there (🔍 search for overwrite), and answer n.

Check: cp printed a line like 'Photos/cat.jpg' -> 'Games/cat.jpg' for each picture; the two pictures are both in Photos and in Games, and snow_dog.jpg is in winter; the last cp asked cp: overwrite 'Albums/books.txt'?. → Managing Files · Reading the Manual
Copy a directory: Copy the whole Games directory to /tmp/Games_backup. Then run exactly the same command a second time, and find out where the second copy went. Delete only the second copy.

Check: tree /tmp/Games_backup shows the same files as tree ~/lab02/Games, and nothing more. → Managing Files
Rename and move: Rename groceries.txt to shopping.txt and move it into Recipes with a single mv. Move plan.txt and books.txt into Albums with a single command.

Check: Recipes has shopping.txt; Albums has books.txt and plan.txt; no .txt file is left directly in ~/lab02. → Managing Files
Delete: Delete /tmp/Games_backup/chess.txt. Move sudoku.txt from puzzles up into Games/2026, then delete the empty puzzles directory. Then delete Albums/2024 and everything in Albums/2025 using only rmdir and rm (no -r). Make rm ask you before it deletes every file (look in man rm, 🔍 search for prompt).

Check: rm asked remove regular empty file ...? before every file; Albums has only books.txt and plan.txt, and Games/2026 has only sudoku.txt. → Managing Files · Reading the Manual
Spaces in names: In ~/lab02/Recipes, create the directory Shopping Lists and, inside it, the files week 1.txt and week 2.txt with a single command. Copy week 1.txt to /tmp, and rename week 2.txt to last week.txt. At the end, delete the whole Shopping Lists directory.

Check: ls /tmp shows 'week 1.txt'; before the last step Shopping Lists has week 1.txt and last week.txt, and after it Recipes no longer has Shopping Lists. → Names with Spaces and Special Characters
Install Yazi: Install Yazi.

Check: yazi --version prints a version number. → Installing Yazi on Fedora 44
Look around: Open ~/lab02 in Yazi. Walk down into Albums and back up to ~/lab02, first with the arrow keys, then without them. Make the hidden file appear, then hide it again.

Check: .secret appears and disappears. → Using Yazi
Create and rename: With Yazi only, in ~/lab02, create a file menu.txt and an empty directory Drafts. Rename menu.txt to dinner.txt, and rename soup.txt in Recipes to tomato_soup.txt.

Check: tree shows dinner.txt, Drafts and Recipes/tomato_soup.txt. → Using Yazi
Copy and move: With Yazi only, copy dinner.txt into Recipes. Move dog.jpg from Photos into Drafts.

Check: dinner.txt is both in ~/lab02 and in Recipes; dog.jpg is in Drafts and no longer in Photos. → Using Yazi
Tabs: With Yazi only, open Albums, Recipes and Drafts in three different tabs. Without leaving any of the three directories:
- copy plan.txt into Recipes;
- move shopping.txt into Albums.
Check: plan.txt is both in Albums and in Recipes; shopping.txt is in Albums and no longer in Recipes. → Tabs

🏠 Going Further

Calculate: Go to ~/lab02/Games. Create the file ~/lab02/answers.txt with nano, without leaving Games. In it, write the absolute path of each of these relative paths:
- ../Photos/cat.jpg
- ./2026/../chess.txt
- ../../lab02/Recipes/.
- 2026/../../Albums/books.txt
- ../Games/2026/../../Photos/./cat.jpg
- ../../../../..
Check: realpath prints the same absolute paths as the ones you wrote. → From Relative to Absolute
Above the root: Go to / and try to go even higher. Find out, with realpath and ls, where /../../.. leads. From /, reach ~/lab02 with a relative path that starts with ../...

Check: pwd prints / no matter how many times you try to go up, and the last cd works. → . and ..
Home from anywhere: List ~/lab02 from /usr/bin, from /tmp and from /usr/share/doc, each time with a relative path. Write in answers.txt how many .. you needed each time. Then let realpath calculate, for each of the three directories, the relative path from it to ~/lab02 (look in man realpath, 🔍 search for relative).

Check: the three commands print the same files, and realpath prints the same relative paths as yours. → The Home Directory: ~ · Reading the Manual
Fix the path: Each of these commands fails. Find out why and fix it:
- ls ~/lab02/games/2026
- cd ~/lab02/Games/chess.txt
- ls ~/lab2
- ls ~/lab02/Photos/cat.jpg/
- cd ../lab02/Games (run it from ~/lab02/Photos)
Check: the commands print no error. → Troubleshooting
More tree: Show the tree of ~/lab02 (look in man tree for the options):
- only the directories, but also the hidden ones (🔍 search for only and for hidden);
- with the hidden files, two levels deep;
- with the size of every file, in K / M, and the directories listed before the files (🔍 search for human and for before).
Then show only the directories of /usr, two levels deep.

Check: only the second command shows .secret; in the third one, every name has its size in brackets, like [4.0K], in front of it, and in every directory the subdirectories come first. → Navigation · Reading the Manual
Not too deep: Find the .txt files of ~/lab02 that are at most two levels deep (look in man find, 🔍 search for levels). Then find all the empty files in ~/lab02 (🔍 search for empty).

Check: chess.txt and the files in Albums and Recipes appear, but not sudoku.txt; the empty files include chess.txt and cat.jpg, but not plan.txt. → Finding Files · Reading the Manual
Somewhere in the system: Find the file called hosts in /etc, and every file whose name starts with passwd in /etc. Ignore the Permission denied messages. Then find, in /usr/share/doc, the files called readme, written with any upper or lower case letters: README, Readme, ... (look in man find, 🔍 search for insensitive).

Check: the results include /etc/hosts and /etc/passwd, and the last command finds many files called README. → Finding Files · Reading the Manual
Settings of the package manager: Find, somewhere in /etc, the file called dnf.conf (the settings of dnf, the program that installs packages). Print it using the path that find printed.

Check: the file is /etc/dnf/dnf.conf, and it has a line [main]. → Finding Files · Viewing Text Files
Names of computers: Print /etc/hosts, the file that gives names to network addresses, and find the line with localhost. Then open it with nano -v and search for localhost with Ctrl+W.

Check: the line starts with 127.0.0.1, the address of your own computer. → Viewing Text Files
The kernel: Find the files of the kernel in /boot (their names start with vmlinuz), then show their details with the sizes in M (look in man ls, 🔍 search for sizes).

Check: you find at least one vmlinuz-... file, of a few MB. → Finding Files · Navigation · Reading the Manual
Logs: List the details of /var/log, the directory where the system keeps its logs, with the files changed most recently at the top (look in man ls, 🔍 search for newest). Try to print some of the text files there (check them with file first): find one that you are allowed to read, and one that you are not.

Check: the dates go from the newest to the oldest, and for one of the files you get Permission denied. → Viewing Text Files · Reading the Manual
Look, do not touch: Try to create /etc/test.txt, to save /etc/hosts from nano after adding a letter (exit without saving after the error), and to delete /etc/hosts (if rm asks remove write-protected regular file?, answer y).

Check: every attempt prints Permission denied, and /etc/hosts is unchanged. → Troubleshooting
Moving around the system: From /usr/share/doc, go to /etc with the shortest relative path, then to /var/log with another relative path, and back to /usr/share/doc with a third one. Jump to /var/log with cd -.

Check: after each cd, pwd prints the directory you wanted to reach. → Relative Paths · The Previous Directory: cd -
The extension lies: Copy /usr/bin/ls to /tmp/song.mp3 and /etc/hosts to /tmp/program, and find out what they really are. Then run /tmp/song.mp3 ~/lab02. Delete both copies at the end.

Check: song.mp3 is an ELF executable and program is text; /tmp/song.mp3 ~/lab02 lists ~/lab02, exactly like ls ~/lab02. → What Kind of File
Paths everywhere: From ~/lab02/Games/2026, without changing the current directory, copy cat.jpg from Photos into Recipes using only relative paths. Delete the copy, then copy it again using only absolute paths. Copy it a third time, with relative paths, so that cp asks before overwriting it, and answer y.

Check: Recipes has cat.jpg, and the third cp asked cp: overwrite '../../Recipes/cat.jpg'?. → Every File is a Path · Reading the Manual
Delete a directory: Delete /tmp/Games_backup with everything inside it with a single command, and make rm print everything it deletes (look in man rm, 🔍 search for explain).

Check: the last line printed by rm is removed directory '/tmp/Games_backup', and ls /tmp no longer shows it. → Managing Files · Reading the Manual
Strange names: In /tmp, create the files rock & roll.txt, price $5.txt, it's here.txt and -help.txt. Check the names with ls -l, then delete the four files, with one rm for each of them.

Check: ls -l /tmp shows the four names exactly as above, and none of them at the end. → Names with Spaces and Special Characters
Several files: With Yazi only, copy both pictures from Games into Albums with a single paste. Then move tomato_soup.txt, pizza.txt and cake.txt from Recipes into Drafts with a single paste, and move pizza.txt and cake.txt back into Recipes with another single paste.

Check: Albums has cat.jpg and dog.jpg; Drafts has dog.jpg and tomato_soup.txt; Recipes has pizza.txt and cake.txt. → Using Yazi
Trash or delete: With Yazi only, send dinner.txt (the one in ~/lab02) to the trash, and delete Drafts permanently. Then, from the terminal, find dinner.txt in the trash and move it back to ~/lab02.

Check: dinner.txt is back in ~/lab02, and Drafts is gone. → Using Yazi

📝 Challenges

Tricky paths: From ~/lab02/Photos, calculate where ../Games/2026/./../../Photos/../Recipes leads, and write each step of the calculation in answers.txt. Go there with a single cd. Then go back to Photos with a path that contains exactly two ...

Check: you are back in /home/student/lab02/Photos. → From Relative to Absolute
Reorganize: Using the terminal for half of the work and Yazi for the other half, change ~/lab02 so that tree ~/lab02 prints exactly this tree (delete everything that is not in it):
```
/home/student/lab02
├── Games
│   ├── 2026
│   │   └── sudoku.txt
│   ├── cat.jpg
│   ├── chess.txt
│   └── dog.jpg
├── Notes
│   ├── books.txt
│   └── plan.txt
└── Recipes
    ├── desserts
    │   └── cake.txt
    └── pizza.txt
```
Try to use as few commands as possible, and write their number in answers.txt before deleting it.

Check: compare your tree ~/lab02 with the tree above, line by line (the order of the lines does not matter). → Managing Files · Using Yazi

info

Exercises 56 - 62 start from the tree of exercise 55: do them only after tree ~/lab02 shows exactly that tree.

Exactly five: From ~/lab02/Recipes/desserts, write a relative path to sudoku.txt that contains exactly five .. and no .. Use it with ls -l.

Check: ls -l shows sudoku.txt, and realpath of your path prints /home/student/lab02/Games/2026/sudoku.txt. → From Relative to Absolute
Shortest path: Find the shortest relative path from /usr/share/doc to ~/lab02/Notes, and the shortest one from ~/lab02/Notes back to /usr/share/doc. Use each of them with a single cd, then jump between the two directories twice more with cd - only.

Check: after each cd, pwd prints the directory you wanted to reach. → Relative Paths
Clean up a path: Write the shortest absolute path equivalent to /home/../../../home/student/lab02/./Notes/../Games/2026/../../Recipes/desserts/.., first on paper, then check it.

Check: realpath prints the path you wrote. → From Relative to Absolute
Swap: Swap the names of Notes/books.txt and Notes/plan.txt using only mv.

Check: ls -l ~/lab02/Notes shows that books.txt now has the size that plan.txt had before, and plan.txt is empty. → Managing Files
Mirror: Create in /tmp/mirror the same directory structure as ~/lab02 (only the directories, no files), with a single mkdir command that prints every directory it creates (look in man mkdir, 🔍 search for message).

Check: mkdir printed a created directory line for every directory, and the trees of /tmp/mirror and ~/lab02 have the same directories. → Managing Files · Reading the Manual
From far away: Go to /tmp. With a single mv command and only relative paths, move chess.txt and cat.jpg from Games into Recipes/desserts. Then move them back with a single mv, this time from ~/lab02/Notes.

Check: after the first mv, desserts has three files; after the second one, tree ~/lab02 shows the tree of exercise 55 again (with the names of exercise 59). → Every File is a Path
Backup with tabs: With Yazi only, create the directory ~/lab02/Backup, then copy the Games, Notes and Recipes directories into it using two tabs and a single paste. Delete Backup permanently at the end.

Check: before deleting it, tree ~/lab02/Backup shows the three directories with all their files. → Tabs · Using Yazi

Wrap-up Questions

Use the last 5 minutes of the lab to answer these questions together with your colleagues and the teaching assistant. There are no wrong answers for the last two.

What is the difference between an absolute and a relative path? How can you tell them apart at a glance?
What do ., .. and ~ mean?
Why does a relative path stop working when you change the current directory?
How does the operating system turn a relative path into an absolute one?
What does [ ] and ... mean in the SYNOPSIS of a manual page?
Why must the last parameter of cp a b c be a directory?
What is the difference between rm in the terminal and d in Yazi?
When would you use the terminal, and when Yazi?
What was the hardest path to calculate today?

Extra

Hidden files: Run ls -a ~. Most of the hidden files and directories are settings of your programs. Find the directory where Yazi keeps the trash. → Using Yazi
The whole tree: Run tree -L 1 / and compare it with the tree in The File System Tree. Find in /etc the file that says which Linux this is, and print it (hint: its name ends with release). → The File System Tree
Yazi help: Press F1 in Yazi and find the key that filters the files in the current directory by name. → Using Yazi
Ghostty: Install Ghostty, open ~/lab02/Photos with Yazi inside it and compare it with Yazi in foot. Then make Ghostty the terminal that opens with $mod + Enter. → A Better Terminal for Yazi: Ghostty

Objectives​

Resources​

The File System Tree​

Hidden Files​

Paths​

The Current Directory​

Absolute Paths​

Relative Paths​

. and ..​

From Relative to Absolute​

The Home Directory: ~​

Every File is a Path​

Reading the Manual​

Searching in a Manual Page​

Working in the Terminal​

TAB Completion​

Editing a Command​

Scrolling the Terminal​

Navigation​

Examples​

pwd​

cd​

The Previous Directory: cd -​

ls​

tree​

Finding Files: find​

Examples​

Viewing Text Files: cat and nano​

cat​

nano​

cat or nano?​

What Kind of File: file​

Managing Files​

Names with Spaces and Special Characters​

Examples​

mkdir​

touch​

nano​

cp​

mv​

rmdir​

rm​

Yazi​

Installing Yazi on Fedora 44​

A Better Terminal for Yazi: Ghostty​

Using Yazi​

Tabs​

Troubleshooting​

Exercises​

🧪 First Steps​

🏠 Going Further​

📝 Challenges​

Wrap-up Questions​

Extra​

Objectives

Resources

The File System Tree

Hidden Files

Paths

The Current Directory

Absolute Paths

Relative Paths

`.` and `..`

From Relative to Absolute

The Home Directory: `~`

Every File is a Path

Reading the Manual

Searching in a Manual Page

Working in the Terminal

`TAB` Completion

Editing a Command

Scrolling the Terminal

Navigation

Examples

`pwd`

`cd`

The Previous Directory: `cd -`

`ls`

`tree`

Finding Files: `find`

Examples

Viewing Text Files: `cat` and `nano`

`cat`

`nano`

`cat` or `nano`?

What Kind of File: `file`

Managing Files

Names with Spaces and Special Characters

Examples

`mkdir`

`touch`

`nano`

`cp`

`mv`

`rmdir`

`rm`

Yazi

Installing Yazi on Fedora 44

A Better Terminal for Yazi: Ghostty

Using Yazi

Tabs

Troubleshooting

Exercises

🧪 First Steps

🏠 Going Further

📝 Challenges

Wrap-up Questions

Extra