progmamun/linux

Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged in a Linux distribution.

• DNS google: 8.8.8.8 8.8.4.4

• $ cd ~/Downloads/

• Extract file .tar.gz ( $ tar -xzvf file_name)

• ll(folder er sob kicu dekaba)

• sudo apt-get autoremove

• sudo rm -rf /tmp/*

• sudo apt-get update

• sudo apt-get upgrade or sudo apt-get dist-upgrade

• sudo apt-get source

• sudo apt-get purge (remove)

• sudo apt-get clean

• sudo apt install nodejs npm

• sudo apt remove nodejs npm

• NVM:

1. gitlink -cmd
2. source ~/.bashrc
3. nvm install <version-16.8.0> 4.nvm use change version

• ctrl+alt+t >open terminal
• ctrl+l > clear
• ctrl+d > close terminal
• Reading the Man Pages
• $ man -k which
• $ man 1 sol
• Redirection Standard Output
• $ cat
• $ cat 1> output.txt
• $ cat > output.txt (same upline)
• $ cat 1>> output.txt (over right old txt still there)

Redirection Standard input + Standard Error

• $ cat 2> error.txt
• $ cat 2>> error.txt
• $ cat 1>> output.txt 2>> error.txt
• $ cat >> output.txt 2>>error.txt
• $ cat > input.txt
• $ cat < input.txt
• $ cat 0< input.txt 1> hello.txt (other terminal open and run $ tty)
• $ cat 0< input.txt > /dev/pts/1 communication two terminal

Piping

• $ date 1> date.txt
• $ cut < date.txt --delimiter " " --fields 1
• $ date | cut --delimiter " " --fiels 1
• $ date | cut > today.txt --delimiter " " --fields 1
• $ date | cut --delimiter " " > today.txt --fields 1
• $ date | cut --delimiter " " -fields 1 | command -options args
• $ date | tee fulldate.txt | cut --delimiter=" " --field=1
• $ date | tee fulldate.txt | cut --delimiter=" " --field=1 > today.txt
• $ date | tee fulldate.txt | cut --delimiter=" " --field=1 | tee today.txt
• $ date | xargs echo
• $ date | xargs echo "hello"
• $ date | cut --delimiter=" " --fields=1 | xargs echo

Navigating the file system

• $ pwd
• $ ls
• $ ls -lh
• $ cd ~/Downloads
• $ cd Downloads
• $ cd (back home)
• $ ls -a (hidden file show)
• $ cd . (refesh)
• $ cd .. (back)
• $ cd etc

Creating Files and Directories

• $ touch files1
• $ touch ~/Documents/distantfile
• $ echo "hello" > hello.txt
• $ mkdir -p new/thing/index
• $ mkdir happy birthday (2 folder)
• $ mkdir "happy birthday"
• $ mkdir {jan,feb,mar,apr}_{2021,2022,2023,2024}
• $ mkdir {jan,feb,mar,apr,may,jun,jul,aug,sep,oct,nov,dec}_{2017..2022}/file{1..100}
• $ touch file{A,B,C}.txt
• $ touch file{F..v}.txt

Deleting Files and Folders

• $ rm deleteme
• $ touch Doucments/deleteme
• $ rm Doucuments/deleteme
• $ rm file1.txt Doucments/file2.txt Downloads/file3.txt
• $ rm _.txt
• $ rm file_
• $ rm 2
• $ rm -r delfolder/
• $ rm -ri delfolder/
• $ mkdir -p delfolder/folder{1..3}
• $ touch delfolder/folder{1,2}/file{1..10}.txt
• $ rmdir delfolder/_ (rmdir deleted empty directory)
• $ rm -r project/

Copying Files and Folders

• $ cp file1.txt file2.txt
• $ cp file1.txt file2.txt destination/
• $ cp destination/_ .
• $ cp destination/_ ..
• $ cp -r copy_me/ destination/ (folder copy)

Moving + Renaming Files and Folders

• $ mv oldname.txt newname.txt
• $ mv newfolder/_ .
• $ mv file* newfolder/
• $ mv newfolder/ ~/Documents/
• $ mv ~/Documtns/newfolder/ ./jackpot (= home folder)

Editing Files using Nano

• ctrl+o (save) then enter
• ctrl+x (exit)
• $ sudo nano /etc/nanorc
• ^ = ctrl
• M- = alt, esc or cmd (depending on your layout).
• nano's configuration file is /etc/nanorc

The Locate command

.conf .log

• $ locate *.conf
• $ locate -i _.CONF (insensitive letter when use i)
• $ locate -i --limit 3 _.conf
• $ locate -S (inf database)
• $ locate -S > ~/Desktop/database*before.txt
• $ locate -e *.conf
• $ locate --existing _.conf (same result)
• $ locate --follow _.conf
• $ locate --existing --follow -i --limit 5 _.conf
• $ sudo updatedb
• $ man updatedb

The Find command

• $ find /home/mamun/Documents/
• $ find . -maxdepth 1
• $ find . -maxdepth 2
• $ find . -maxdepth 4
• $ find . -type f
• $ find . -type d
• $ find . -maxdepth 1 -type d
• $ find . -name "5.txt"
• $ find . -maxdepth 2 -name "_.txt"
• $ find . -maxdepth 2 -name "file?.txt"
• $ sudo find / -type f -size +100k | wc -l
• $ mkdir haystack/folder{1..500}
• $ touch haystack/folder{1..500}/file{1..100}
• $ find haystack/ -type f -name "needle.txt"
• $ find haystack/ -type f -name "needle.txt" -exec mv {} ~/Desktop ;

Viewing Files

• $ cat file1.txt
• $ cat file[1-5].txt | tac > reversed.txt
• $ tac myfile.mp3 > myreversedfile.mp3
• $ cat file[1-5].txt
• $ cat file[1-5].txt | rev
• $ cat file[1-5].txt | tac
• $ sudo find / -maxdepth 5 -name "_.conf" -size +20k
• $ cat /etc/cups/cups-browsed.conf
• $ tac index.txt
• $ rev index.txt
• $ cat index.txt
• $ find | head -n 5
• $ find | head -n 5 | tac
• $ cat /etc/cups-browsed.conf | wc -l
• $ head -n 20 /etc/cups/cups-browsed.conf
• $ tail -n 20 /etc/cups/cups-browsed.conf (tail- bottom)

Sorting Data

• $ sort index.txt
• $ sort words.txt > sorted.txt
• $ sort words.txt | tac
• $ sort -r words.txt (r=reversed)
• $ sort numbers.txt | less
• $ sort -n number.txt | less
• $ sort -nr number.txt | less
• $ sort -u number0-9.txt | less
• $ sort -u number0-9.txt
• $ ls -l /etc | head -n 20 | sort -k 5n
• $ ls -l /etc | head -n 20 | sort -k 5nr
• $ ls -ln /etc | head -n 20 | sort -k 5nr
• $ ls -lh /etc | head -n 20 | sort -k 5hr (human readable)

Searching File Content

• $ grep e hello.txt
• $ grep -ic a gadsby_manuscript.txt
• $ grep -ic e gadsby_manuscript.txt
• $ grep -i "our boys" gadsby_manusript.txt
• $ wc -l gadsby_manuscript.txt
• $ grep -v e gadsby_manuscript.txt (v= e letter bad a sob dekaba)
• $ grep -cv e gadsby_manuscript.txt (cv letter count korba)
• $ ls -lF / | grep root
• $ ls -lF / | grep opt
• $ ls -F /etc | grep -v / > files.txt
• $ ls -F /etc | grep -v / | sort -r > files.txt
• $ man -k print | grep files

File Archiving + Compression

• $ ls -lh
• $ tar -cvf ourarchive.tar file[1-3].txt
• $ tar -tf ourarchive.tar (t-test what inside the archive file)
• $ tar -xvf ourarchive.tar (extact)
• $ gzip ourarchive.tar
• $ gunzip ourarchive.tar.gz (undo gzip)
• $ bzip2 ourarchive.tar
• $ bunzip2 ourarchive.tar
• $ zip ourthing.zip file1.txt file2.txt
• $ unzip ourthing.zip
• $ tar -cvzf ourarchive.tar.gz file[1-3].txt
• $ tar -cvjf ourarchive.tar.bz2 file[1-3].txt
• $ tar -xvzf ourarchive.tar.gz
• $ tar -xvjf ourarchive.tar.bz2

Bash Scripts

$ nano our_script.sh #!/bin/bash

mdir ~/Desktop/magic cd ~/Desktop/magic touch file{1..100} ls -lh ~/Desktop/magic > ~/Desktop/magic.log $ bash our_script.sh (run) nano backup.sh #!/bin/bash

tar -czf ~/Desktop/backup.tar.gz ~/{Documents,Downloads,Desktop,Pictures,Videos} 2>/dev/null

bash backup.sh

• chmod +x backup .bashrc PATH="$PATH:$HOME/bin" Scheduling With Cron
• $ crontab -e