Basic navigation commands

pwd - present working directory

• Using this command you can print the location of the directory you are working in.
• Usage: pwd

cd - change directory

• Using this command you can change your current working directory.
• Usage: cd path_to_directory
• It accepts both absolute and relative paths
• Shortcut for home is ~
• Shortcut for previous working directory is -
• Shortcut for someone else's home directory is ~username
• To go to home dir just type cd
• Examples:
  • cd ../parent
  • cd ./child/grandChild
  • cd /home/itachi/sharingan/ or cd ~/sharingan
  • cd (will take you to home dir)
  • cd ~levi (cd to levi's home directory)

ls - list

• Using this command you can list the contents of any directory, as long as you have proper permissions.
• Usage: ls path
• The file names starting with period (.) are hidden in linux.
• To list the hidden files use -a flag.
• To print additional info about the files and directories in linux use the -l flag, it stands for long list.
• Tip: ll is an alias for ls -l
• It accepts relative and absolute paths.
• You can even specify multiple locations seperated by spaces.
• Use -h flag to display file sizes in human readable format rather than in bytes.
• Long list:
  • Examples:
    • -rw-r--r-- 1 sup3r541y4n sup3r541y4n 2180 Dec 5 20:43 navigation.md
    • drwxr-xr-x 1 sup3r541y4n sup3r541y4n 184 Dec 5 20:41 Linux
  • The first character represents the type of file (directory(d), file(-), symbolic link(l), character special file(c) and block special file(b))
  • The next 3 characters represent the file permissions of the owner (read(r), write(w) and execute(x))
  • Read:
    • File: Allows a file to be opened and read.
    • Directory: Allows a directory’s contents to be listed if the execute attribute is also set.
  • Write:
    • File: Allows a file to be written to or truncated; however, this attribute does not allow files to be renamed or deleted. The ability to delete or rename files is determined by directory attributes.
    • Directory: Allows files within a directory to be created, deleted, and renamed if the execute attribute is also set.
  • Execute:
    • File: Allows a file to be treated as a program and executed. Program files written in scripting languages must also be set as readable to be executed.
    • Directory: Allows a directory to be entered, e.g., cd directory .
  • The next 3 characters represent the file permissions of the group.
  • The next 3 characters represent the file permissions of everyone else.
  • Next is the number of hard links of the file.
  • Next is the username of the owner.
  • And then comes the group which owns the file.
  • The numbers after than repesent the size of the file in bytes
  • Then comes the date and time of file's last modification
  • And at last comes the name of the file
• Examples:
  • ls (List current directory)
  • ls -al (List everything including hidden files and mke it a long list)
  • ls pathToFileOrDirectory
  • ll (alias for ls -l)