Hey guys,
I've been using linux for a while and I'm looking back at my written notes on linux shell use. I'm trying to type them in my computer to be a bit more organized (and in case I lose my notes, I have something backed up). I thought as I slowly get them into my computer that I would share with you guys what I've learned. I'll fix it up as I have more time and let me know if something doesn't look right... anyways Enjoy.
General command syntax
ls – shows list of a directory
cd – change directory
cd ~
~ shows user home folder
changes your directory to the home folder
cd -
the - at the end of cd brings you to the previous directory
sort – sorts based on alphabet?
sort – sorts out redundancies in a file
sort -u dupes.txt
-u unique (no repeating lines)
grep – basically searched files with specific keywords in them
grep – search files for text that matches a given pattern.
grep “the” poems.txt
Basically find where the word “the” shows up in poems.txt
man – view the reference manual or man page for a specific command (-h works too)
ls -l does more info in the list
mkdir – makesdirecotry
rm – removes
cp – copy
EX: First file is the copied file, second file is the pasted
cp hello.txt hello_there.txt
. shows us our current directory
su root – maintains super user rights
cat – concatenate and print files
vi – open vin text editor In shell
find - command looks for files
EX: find . -name “do*”
. – find file in current directory
-name – find file by name
“do*” – find file with the name do followed by any character afterwards
Quick Buttons
CTRL+SHIFT+(+) makes the font bigger
CTRL+A – moves to the beginning of the line
CTRL+E – moves to the end of the line
CTRL+left arrow – moves backwards a word
CTRL+right arrow – moves forward a word
CTRL+U – deletes from cursor to the beginning of the line
CTRL+k – deletes from cursor to the end of line
CTRL+SHIFT+C – copy to clipboard
CTRL+SHIFT+V – paste from clipboard
File permissions
rwxrwxrwx the_file
you can look at it as rwx – user: rwx - group : rwx - others
First group of rwx is the user
Second group is the group
Third group is the others
R – read
W – write
X - execute
Chmod – changes the perissions on a file by modifying the file made bits
There are different things for representations
Octal (755, 644)
Symbolic (=, -, +)
To change permissions for all users in a directory
Chmod a-x test.sh
Table Read (4 points) Write (2 points) Execute (1 point) Result
User R W X 7
Group R - X 5
Others R - - 4
Symbolic Read Write Execute Result
User (u) + + + U=rwx
Group (g) = - - G = r
Others (o) - - - O = nothing
Chown – change ownership
Misc
wildcards - are characters that stand for patters
(*) any number of characters
? one of any character
sudo -k – gets out of sudo
./ - executes a program
./calculator
| - (pipe character) takes the output of one command and sends it to another. Type it in between commands
echo – same thing as print or echo in php
cat – concatenate and print files
head and tails – command lets us see the beginning and the end of the text file.
Head poems.txt
-n – in head shows how many lines after you gonna show
awk and sed – tools that extract or modify text from a file or stream
awk ‘{print $2}’ simple_data.txt
sed s/orange/red/ simple_data.txt
s substitutes every occurrence of orange with red
tar files – type archive files
Basically they are files within a big file
Tar -cvf myfile.tar Exercisefiles/
-c create an archive
-v list out each file that gets added to the archive
-f output to a file
To find your distribution type:
Cat /etc/*-release or uname -a
free -h shows your ram
cat /proc/cpuinfo
Shows random things within the computer
(for fedora) sudo dnf install nano
dnf shows what you are about to install on the machine
(for ubuntu (Debian))
sudo apt-get update
Advanced package tool
Cloning things from github:
git clone git://github.com/<github directory>
You should definitely know about: https://github.com/chubin/cheat.sh (https://github.com/chubin/cheat.sh)
linux-commands-cheat-sheet-new.pdf > https://docdro.id/oQU2bTG (https://docdro.id/oQU2bTG)
(https://funkyimg.com/i/2TM5H.png)
(https://images.weserv.nl/?url=i.imgur.com%2F1EJLOqd.png)
(https://images.weserv.nl/?url=i.imgur.com%2FRxlwP.png)
(https://images.weserv.nl/?url=i.imgur.com%2FyWfCliF.png)
(https://images.weserv.nl/?url=i.imgur.com%2FrUATjIG.png)
Ok, this is amazing. Thanks for this.