Linux terminal command ( Arch and Debian )

• ~ : home directory
• # : Root
• $ : User
• & : run commands in the background of your terminal
• && : combine multiple commands together
• > : re-director, take the output from a command (such as using cat to output a file) and direct it elsewhere
• >> : similar to > but instead of replacing the output, it will add it to the one already present
• –help or -h : put after the command name will show the help menu
• adduser username : to add a user
• alias : shows the shell’s aliases
• apt search packagename : search all the package with that name on it
• apt update : Debian update the system by downloading new packages
• apt upgrade : Debian install the downloaded packages
• apt install : Debian install a program/application
• apt remove : Debian remove program/application
• apt autoremove : Debian remove program/application orphan dependencies
• bc : basic calculator
• cat : shows every line inside the file from the terminal
• cd : change directory (“cd download” if you want to go to the download directory)
• cd – or cd .. : to go back to the previous directory
• chage -E date user : set expiration date for the user
• chage -l user : shows the expiration date of the user ( type -1 for never )
• chage -M days user : to set the number of days the user had to change password
• chmod : change file permission (Example: 764 = rwxrw-r–)
  [d|rwx|rwx|rwx = dir/file|user|group|other]  [4+2+1 = rwx = read write execute]
• chmod +x filename : add execute to all
• chmod -x filename : remove execute to all
• chmod u+x filename : add execute to user only
• chsh -l : to check the path of the shell
• chsh -s /path/of/the/shell : to set the new shell for the user
• clear or “Ctrl” + “l” : clear the terminal
• “Ctrl” + “+” : zoom in
• “Ctrl” + “-“ : zoom out
• cp filename directory : copy and paste the file in the directory
  
• date : shows the date
• df -h : shows availible and used disk/partiton space
• diff filename1.txt filename2.txt : to check if there is difference inside the files
• echo : displays what did you type
• EDITOR=nano visudo :from root to edit with nano /etc/sudoers privileges (if member of the wheel: remove #)
• fdisk : to start modifying the disk partitions (umount device first)
• fdisk -l : shows disk and partitions
• free : shows memory and swap usage in byte
• free -m : shows memory and swap usage in Mb
• grep word filename : shows the specific word in a specific file
• grep word * : shows the specific word in every file in that directory
• grep -c word filename : count how many time the word is in that file
• grep -i word filename : same as grep alone but with no case sensitivity
• grep -n word filename : same as grep but shows also the line number
• grep -r word /path/ : shows the word inside every file and evry folder from that path 
• grep -v word filename : shows every line apart for the one containing that word
• grep -name filename : to look for a specific file
• groups user : to check all the groups that the specific user is in
• help : help page documentation of the program selected
• head : print out first 10 line on the selected file
• history : it will show the command history
• htop : system monitor
• id : user identity
• ip : shows/manipulate routing, net devices and so on
• ip address : shows your IP address
• kill : close the program
• less : similar to cat, mainly used for longer files
• locate : locate the file or directory
• ls : list file and directory
• ls / : list files in the fist directory
• ls -a : list all file and directory (even the hidden one)
• ls -all or ll -a : list all file and directory + other information
• ls -lah : list all file and directory + other information in human readable number 4k instead 4000
• lsblk : list all disks and partitions
• lsplug : list all usb devices
• lspci : list pci devices
• man : manual, it’s basically the manual for another program, you can even type “man man“
• makepkg -s : run the command inside the directory of the tar -xvf extracted file to create an installation file
• mkdir : create a directory (folder)
• mkfs.typefile /dev/devname: to format the disk with the type file (ext4/exfat). create 1st partitions with fdisk
• mkfs.ext4 -n “label” /dev/devname : to label the device or partition
• mount : shows all the volumes on every disk
• mount | grep diskname : filter only the volumes on the specified disk
• mv filename directory : move file to directory
• mv filename1 filename2 : to rename file
• mv *.txt directory : to move all file with that extension
• ncdu : shows how much space is used and by which folder inside the directory
• ncdu / : shows for the all system
• ncdu / -x : same as above but only for the local system, excludes the external drives
• net : tool to administrate samba and CIFS servers
• nmap -sV ipaddress : shows port and version
• nmap -v : check the nmap version
• nmap ipaddress.0/24 : scan entire subnet (nmap -sP ipsubnet shows a simplified view)
• nmap ipaddress or hostname : to scan all the ports on that system
• nmap -T5 ipaddress : to scan at maximum speed
  [ From T1 (slower but less detectable) to T5 (faster and less accurate), default is set to T3]
• pacman -Qdt : queering package database for orphans, so they can be removed
• pacman -R: Arch program remove
• pacman -S: Arch program install
• pacman -Ss keyword : Arch program search for packages using keyword
• pacman -Syu : Arch to update/upgrade
• pacman -Syy : Arch refresh package databese
• pacman -U filename : use it inside the directory where the file to install the selected file after makepg -s
• passwd -l user : lock the user sccount
• passwd -u user : unlock the user sccount
• ping ipaddress: test and send packages to the specify web address
• ps : process status
• pwd : print working directory (shows you where you are)
• reboot : reboot the system
• rmdir : remove directory
• rm filename : remove file
• rm -rf directory or filename : forcefully remove directory and all it’s files
• samba : server that provides services to clieants
• sar -b : to check why system is slowing down
• sar -r : to check current memory
• sar -S : to check current swap
• sar -u : to check current cpu usage
• sar -u -f /etc/var/log/sysstat/filename : to check the specific log that was saved
• ss : investigate sockets
• ssh username@ipaddress : to log in using ssh
• su : to switch to root
• su username : to switch to the username
• sudo : obtain administrator privileges
• sudo !! : to run the last command if you forgot to put sudo on the front
• tail : print out last 10 line of the select file
• tar -xvf filename : extract the wget downloaded compressed file
• time commandname : shows how much time the command took
• top : shows all the running program
• touch filename.txt : to create a text file (or you can create one with the text editor: nano filename)
  
• umount /dev/devname : unmount the device or partition but still able to see it
• unalias aliasname : remove the alias
• uname : info on device
• usermod -aG group user : add the specific user to the specific group ( type ” , ” without spaces to add more groups )
• usermod -d /testhome/testdir/ –move-home username : to move the user’s home directory to a new one with all it’s files
• usermod -e date user : to set an expiration date for the user
• usermod -l newname oldname : to change user’s name
• usermod -L user : to lock that specific user
• usermod -U user : to unlock that specific user
• visudo : to edit configuration file, temporary saves it and checks the syntax for error
• wget : non interactive network downloader “wget URL“
• whereis : path the command select + man page
• which command : path to the command select “which ls”
• who : who is logged in
• whoami : to check the name user
• yay : same as pacman but for AUR (automated)
• yay -Syu : update/upgrade standard and AUR