Linux Command Line Tutorial For Beginners 2 - ls command in Linux

Summary

This Linux command line tutorial for beginners focuses on the 'ls' command, which lists directory contents. The video demonstrates how to open the terminal, use basic 'ls' syntax, and navigate directories. It explains various options like 'ls -l' for long format listing, 'ls -a' to show hidden files, and sorting by size with 'ls -lS'. The tutorial also covers how to output 'ls' results to a file and use wildcards for file extensions. The presenter encourages viewers to use 'man ls' for comprehensive command reference, aiming to enhance their understanding of directory management in Linux.

Takeaways

• 😀 The 'ls' command in Linux is used to list the contents of files and directories.
• 🔑 To open the terminal, press 'Control + Alt + T'.
• 📁 The basic syntax of the 'ls' command includes options followed by the file or directory name.
• 🏠 By default, 'ls' without any options lists the contents of the current home directory.
• 📂 Using 'ls' with a directory name as an argument lists the contents of that specific directory.
• 📁 'ls' followed by a forward slash (/) lists the contents of the root directory.
• 📝 The 'pwd' command shows the current working directory, which is usually the home directory.
• 🔍 The 'ls' command with the '-L' option lists files and directories in a long format, showing detailed information such as permissions, size, and creation date.
• 🔐 The 'ls' command with the '-a' option reveals hidden files, which start with a dot (.).
• 🔄 The 'ls' command with the '-S' option sorts the listed items by size.
• 📝 The 'ls' command can be combined with other options, such as '-aL', to list both hidden files and detailed information.
• 📋 To output the results of the 'ls' command to a file, use redirection with '>' followed by the filename, e.g., 'ls -l > out.txt'.
• 📚 To learn more about the 'ls' command and its options, use the 'man' command followed by 'ls', e.g., 'man ls'.

Q & A

What is the primary function of the 'ls' command in Linux?

The 'ls' command in Linux is used to list directory contents, including files and directories.

How do you open the terminal in Linux?

You can open the terminal in Linux by pressing 'Control + Alt + T'.

What is the syntax for using the 'ls' command with options?

The syntax for using the 'ls' command with options is 'ls [options] [file or directory name].'

What does the 'ls' command display when executed without any options?

When executed without any options, 'ls' displays the contents of the current directory, which is usually the home directory when the terminal is first opened.

How can you list the contents of a specific directory using the 'ls' command?

To list the contents of a specific directory, you can use 'ls' followed by the directory name, e.g., 'ls documents'.

What does the 'ls -l' option do?

The 'ls -l' option lists the directory contents in a long format, showing detailed information such as file permissions, owner, size, and creation date and time.

What does the 'ls -a' option reveal that is not shown by default?

The 'ls -a' option reveals hidden files, which are files and directories that start with a dot (.) and are not displayed by the regular 'ls' command.

How can you combine options to list both hidden files and detailed information?

You can combine options by using 'ls -aL' to list both hidden files and detailed information in long format.

What does the 'ls -S' option do when sorting directory contents?

The 'ls -S' option sorts the directory contents by file size, with the largest files listed first.

How can you output the results of the 'ls' command to a file?

You can output the results of the 'ls' command to a file by using the '>' operator followed by the filename, e.g., 'ls -lS > out.txt'.

What command can you use to get more information about the 'ls' command and its options?

You can use the 'man ls' command to get more information about the 'ls' command, including a description and a list of all available options.

Outlines

00:00

📁 Introduction to the 'ls' Command in Linux

This paragraph introduces the 'ls' command in Linux, which is used to list the contents of directories and files. The tutorial begins by instructing viewers on how to open the terminal using the control-alt-T shortcut. It explains the basic syntax of the 'ls' command and demonstrates its use to list the contents of the home directory. The paragraph also covers how to list contents of specific directories by specifying their names and how to verify the current directory using the 'PWD' command. Additionally, it mentions the use of the 'clear' command to clean the terminal screen.

05:02

🔍 Exploring Advanced 'ls' Command Options

The second paragraph delves into the advanced options of the 'ls' command. It explains the use of the '-l' option to display files and directories in a long format, which includes detailed information such as user rights, file size, and creation date. The paragraph also discusses navigating directory structures using the '..' notation to move back to parent directories. It further explains how to combine options, such as using '-a' to reveal hidden files and '-l' for a detailed listing, and how to sort directories by size using the capital 'S' option.

10:04

🔎 Filtering and Outputting 'ls' Command Results

This paragraph focuses on filtering the output of the 'ls' command using wildcards and flags. It demonstrates how to list files with specific extensions, such as '.html', by using the wildcard '*.html'. The paragraph also covers how to redirect the output of the 'ls' command to a file using the '>' operator, allowing users to save the results for later reference. Additionally, it explains how to list only directories by using the '-d' option and how to use the 'estx' wildcard to match directory names.

15:07

📚 Accessing Comprehensive 'ls' Command Documentation

The final paragraph provides guidance on how to access the full documentation for the 'ls' command using the 'man' command. It emphasizes the importance of the 'man' command as a reference tool for understanding all available options and flags for any Linux command, including 'ls'. The paragraph concludes with instructions on how to exit the 'man' terminal and encourages viewers to explore the documentation to learn more about the 'ls' command and its extensive capabilities.

Keywords

💡LS command

The 'LS' command is a fundamental command in the Linux operating system that is used to list the contents of files and directories. In the context of the video, it is the central focus, with the tutorial explaining its basic usage and various options to manipulate directory listings. For example, the script mentions using 'LS' to display the contents of the home directory and other directories such as 'documents' or 'downloads'.

💡Terminal

The terminal is a command-line interface for interacting with the Linux operating system. The script instructs viewers to open the terminal using 'Control + Alt + T' and demonstrates how to execute commands within it. The terminal is the primary environment where the 'LS' command and other Linux commands are executed.

💡Options

In the script, 'options' refer to the various flags and arguments that can be used with the 'LS' command to modify its behavior, such as listing files in long format or including hidden files. The video explains how to use these options to customize the output of the 'LS' command, enhancing the user's ability to navigate and understand directory contents.

💡Directory

A 'directory' in Linux is a folder that contains files and other directories. The script explains how to use the 'LS' command to list the contents of directories, such as the home directory or specific folders like 'documents'. Directories are a fundamental concept in Linux file system organization.

💡File

Files are the basic units of storage in a Linux system, containing data and having attributes like size and creation date. The video script uses the 'LS' command to list files within directories, demonstrating how to view and sort files based on their properties, such as size or extension.

💡Long format

The 'Long format' is an option in the 'LS' command, denoted by '-L', which provides a detailed listing of files and directories, including permissions, ownership, size, and creation date. The script illustrates how to use this option to get more information about the items in a directory, such as in the example where 'LS -L' is used to list the contents of the 'documents' directory.

💡Hidden files

In Linux, 'hidden files' are files that start with a dot ('.') and are not displayed by default when using the 'LS' command. The script explains how to use the '-a' option with 'LS' to show these hidden files, which can include configuration files and system files that are typically not meant to be modified by the user.

💡Sorting

The script introduces the concept of 'sorting' directory contents by size using the 'LS' command with the '-S' option. This allows users to organize files in order of their size, which can be useful for managing disk space or finding large files quickly.

💡Wildcard

A 'wildcard' is a character used in command-line operations to match multiple files or directories based on a pattern. In the script, the wildcard '*.html' is used with the 'LS' command to list only files that end with the '.html' extension, demonstrating a way to filter and search for specific types of files.

💡Output redirection

Output redirection is a technique in Linux to send the output of a command to a file instead of the terminal. The script shows how to use the '>' symbol with the 'LS' command to save its output to a file named 'out.txt', which can be useful for creating backups of directory listings or for later review.

💡Man pages

Man pages, or manual pages, are the documentation for commands in Linux. The script mentions the 'man' command as a way to access detailed information about the 'LS' command and its options. This is an important resource for users to learn more about any command's functionality and usage.

Highlights

Introduction to the 'ls' command in Linux, which lists directory contents.

How to open the terminal using the shortcut 'Control + Alt + T'.

Basic syntax of the 'ls' command and its usage with options and file/directory names.

Listing the contents of the current directory with a simple 'ls' command.

Using 'ls' with a directory name to list its contents, such as 'ls documents'.

Listing the contents of the root directory using 'ls /'.

Explanation of the 'PWD' command to display the current working directory.

Using the tilde '~' symbol with 'ls' to represent the home directory.

Clearing the terminal with the 'clear' command.

Navigating back in the directory structure using 'ls ..'.

Using 'ls -L' to list files and directories in long format with detailed information.

Understanding file permissions represented by 'drwxr-xr-x'.

Using 'ls -a' to reveal hidden files starting with a dot.

Combining options 'ls -aL' to list both hidden files and long format details.

Sorting directory contents by size using 'ls -lS'.

Filtering files by extension with a wildcard, such as 'ls *.html'.

Outputting the results of 'ls' to a file using redirection.

Listing only directories with 'ls -D'.

Using the 'man' command to access the manual for more information on 'ls'.

How to exit the manual viewer with 'q' or 'quit'.

Transcripts

hey guys welcome to the next video on

Linux command line tutorial for

beginners and in this video we will

learn about LS command LS is a Linux

shell command that lists directory

contents of files and

directories now first of all let's open

our terminal I have uh told you in the

last video If you press control alt T

then it's going to open your terminal so

just press control alt T to open the

terminal now for the ls command you need

to know some syntax so we all know that

LS command can be given by just writing

LS on the terminal but it has some

options so these options will come in as

a second argument so we can say here

comes the options right and then comes

the file or directory name so you can

say here here comes the file uh or

directory name so you can write FD okay

so LS command comes with options first

and then files and directory now I will

show you what I mean by that so first of

all simple LS command will uh you know

work like this only which list the

content of uh directory so we are uh you

know whenever we open the terminal we

are in the home directory right so we

can just say LS and it will show us the

contents of our home directory which is

uh the desktop or um other document

directory or you know downloads or other

directories the same when you open this

folder when you click here it will also

open the home directory and you will be

able to see all the contents uh of the

directories here so these all the you

know contents are here also so whatever

you see here will be listed here also

okay now the second uh option of using

Lis command is by using a directory uh

name for example we want to see the

contents of uh this document directory

right so our document directory contains

these two files so how we can list uh

the content of this document directory

you can just write LS and then just

write uh documents and then press enter

and it will list all the files which are

there in the documents directory right

in the same way if you want to list out

all the contents in the downloads folder

then I will just say LS downloads okay

and press enter it will show us the

contents of the downloads folder right

so simple now if you want to list out

all the contents of our root folder as I

have shown you in the last video you

just need to give LS and then forward

slash which is our root directory right

and press enter it will show us the

content of our uh root directory and in

here you can verify this by going to

this uh computer option and you can

match all the directories here and here

right now uh by default as I already uh

told you we whenever we open the

terminal we are in the home uh you know

directory right now home directory uh

you can just uh give PWD command and it

will give you what is your home

directory and this is your home

directory right right so you are

presently in your home directory now in

uh uh other the terms when you uh you

know want to uh list out the content of

home directory you can just say LS and

then give this uh till day symbol which

will also give you the same content as

Lis will give you so let's print out Lis

first but uh let me clear all the

commands which I have given earlier so

to clear the terminal you just need to

write clear here so just write clear and

press enter and it will clear your

terminal and clear means your terminal

will be you know blank but when you

scroll up all the you know all the

commands are there so clear means it

will just scroll down a little and it'll

blank out your terminal for you so let's

list out again so LS so it gives me the

content of my home directory and when

whenever you give LS and the till the

symbol this still day also means the

home directory so whenever you press

enter it'll give you the same content

and whenever you do uh LS and you can uh

type the path Pro uh you know by

yourself so home programming knowledge

which is my home directory once again

and when I press enter it will give me

the same uh directory structure right so

there are three command to list out uh

the same thing one is LS which will give

you uh all the contents of your home

directory when you open your terminal

right and then LS till day which will be

uh also giving you the same content so

the till Day means the your home

directory and also your uh you can type

the home directory file path something

like this now let's see some

options so whenever you want to go

inside some directory as I have uh done

so I will just say LS document and uh

you can just list out anything but you

can just write LS and then dot dot and

this dot dot means you want to print out

one step back directory structure right

so whenever you press LS like this it

will give you programming knowledge

because right now we are in home and

then programming knowledge so whenever

we want to uh print the content of Home

folder then uh we just need to give

these two D dots it will tell you just

one folder back right if you want to go

two folders back and you want to list

out the content of uh two folders back

uh content then you can do dot dot and

then forward slash and once again dot

dot and then press enter and and you can

see it will give you your root directory

uh you know directories and file

structure so this will uh you know go to

the root directory because right now we

are in home uh our home you know you

directory so whenever you go one step

back you will be here in your home and

one step back once again you will be in

your root folder okay once again I will

uh clear the screen and then we will

move forward now uh there is uh are some

Flags or options as I told you you can

use with ls files so for example you

give LS minus L and this means you want

to list out all the files and directory

in Long format and when you press enter

it will give you the listings in Long

format let me just uh make it a little

bit bigger and I will give it once again

in this command so clear and LS minus L

and it gives you the you know content in

Long format long format means it will

give you the details uh who is your uh

you know user what are the rights for

this file and what is the size of your

file and at which date this file was

created and the time at which this file

is created right now you may wondering

what is this Dr WXR or what are all

these things so you can see there these

are the user rights so these user rights

are separated by uh this minus uh symbol

so the first uh you know this thing

which is Dr WXR so what does this mean

so d means directory here R means read w

means uh write X means execute and once

again R means write so these are the

rights of the owner owner means so

whoever is logged in so I can uh you

know read WR execute this uh directory

which is desktop right second is the

group right after this minus right so

execute and read are the rights of the

group and then the third is for the

others which is only execute this

directory okay so this is how you can uh

you know list out the long list of files

and directories now there is one more

command which is LS minus a and this

will give you the hidden files also so

this will show you the hidden files also

so just write LS minus a and it will

give give you all the hidden files so

these are dots and double dots and do

Android and Bash history logout do cach

these are all the hidden files so hidden

files in Linux start from dot okay and

they will not be shown here you can see

these uh dot files are not here so

whenever you give LS minus a it will

give you all the hidden files right and

then you can combine uh the options so

you you give LS

minus a for uh showing the hidden file

and then L for showing the long list

then it will give you the hidden file

and long list

com combined okay so press enter it will

give you long list and hidden file right

something like this I will make it a

little bit bigger so you can see it okay

and I will uh just clear the terminal

once again now there are some more

commands for example you can sort

your directory by their size so I will

just give LS minus L for long list and

then when you give capital S it'll sort

your directory by their size so press

enter and you can see the file which has

uh the biggest size is listed first and

then uh this will go down as according

to the size so whatever file has the

lowest size it will be at the bottom and

whatever files or directory has the

biggest size it will go at the top right

so you can sort it something like this

now for example we want to uh you know

list something which uh Only We Know the

extension of so let's uh list for

example uh you can just write LS once

again we will uh list out document list

so just write documents and press enter

and this document has uh this uh

test.html and uh test. CS file but for

example I want to only list out all the

HTML files which are there in the

document folder so what I I can do so I

can just write LS and then I can just uh

write documents and then I will just

give this wild card which is estx so

which uh will be will search for all the

prefix uh which are there right and then

I will just write Dot and then I will

just write HTML so this means I want to

search for all the files which ends with

HTML and then I will press enter and it

only prints out this uh test. HTML which

is correct because we wanted to print

out only HTML files in the other way

when you give uh est. Atrix which means

all the files so whatever all the

extensions and all the names right and

press enter and it will list out these

two files which are there in your

documents directory

right now uh you can also output uh the

content of your LS to a file so for

example I want to uh you know save all

the result which I have listed here to

some file so I will write LS minus for

example L with capital S and then I want

to save all the content to a file so I

can just give this angle bracket and

then the name of the file which uh I

want to uh you know save these content

to so I will just say out.txt by the way

this out.txt is not existing here so it

will create this out.txt and then f fill

all the result of Lis command to this uh

you know out.txt file so this arrow

means the direction of uh the stream so

it'll uh put all the content into the

output right and press enter and you

will be able to see we have one new file

created which is out.txt and when I open

this file then it'll uh just you know

fill all the result of LS minus LS

command to this output file right so you

can do this or you can output the

content of the file also to a file now

the next command is to list out only the

director so for example you want to just

list out only the directories you can

just give uh LS minus D and then you

just need to give uh estx and forward

slash and it will list out all the

direct directory trees okay so you can

see it's not listing out the files but

only the directories right so these are

the all the important commands related

to Lis but this is not all alsis uh is

uh you know having more options and

flags and if you want to know more about

this LS command what you can do so you I

will just clear the terminal first of

all and to know more about this LS

command you you can just write men and

then LS so men is uh you know is a you

can say the dictionary kind of thing for

your Linux commands right and whenever

you give this men command and then uh

give the command name which you want to

see or uh you want to take the reference

of then when you when you click enter

here it'll give you all the options

which you can use with ls so you you can

see LS minus list directory content so

this is the explanation of this and then

you can see all the flags so I have

shown you how to use minus a but I

haven't shown you how to use minus B so

you can find out all the you know

important information what this minus B

does or what this minus C does or what

this minus D does so d as I've shown you

list directory entries right and uh I

have also shown you what L does so I

have only shown you the important

command related to LS but there is a big

list uh which you can uh you know

execute with this LS command so you just

need to write M man and then LS and it

will give you this kind of interface

which you can see the reference right

and you can see at the bottom whenever

you press Q or write quit then you uh

quit this man terminal so I will just

press Q which will quit the uh terminal

right so just remember this man command

if you want to take the reference of all

the all the you know references of

particular commands so I hope you have

enjoyed this video please writ com And

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