Linux Directory and File Commands Lab

Linux File System and Commands

• Linux file system allows for structured storage of information using files consisting of bits ('0' or '1').
• Rules for naming files in Linux include:
  • No spaces allowed; use underscores instead.
  • Names must start with an alphabet character.
  • Special characters like $, *, %, @, /, etc., are not permitted.
  • File names are case-sensitive (e.g., "City", "city", and "CITY" are distinct).

File Creation and Management

• Use cat command to create a file:

  • Syntax: $ cat > file_name
  • Save contents with Ctrl + D to exit.
  • Example: $ cat > city.txt creates a text file named city.txt.

• Display file contents:

  • Use cat file_name to view contents on the screen.

Editing and Modifying Files

• Add data to an existing file:

  • Use cat command and save with Ctrl + D.

• Display contents of multiple files:

  • Use $ cat file1 file2 to view combined contents.

• Create an empty file:

  • Use touch command: $ touch filename.

Viewing File Contents

• Use more to view file contents one screen at a time, with options for line numbers and screen size.

Moving and Renaming Files

• Use mv command for moving and renaming files:
  • Syntax: $ mv [options] source destination.
  • Moving example: $ mv ~/temp/file.txt . moves a file to the current directory.
  • Renaming example: $ mv file.txt ~/temp/file2.txt renames a file.

Copying Files

• Use cp command to copy files or directories:
  • Syntax: $ cp [options] source destination.
  • Copying example: $ cp file.txt ~/temp/ copies file to a directory.

File Deletion

• Use rm command to delete files:
  • Syntax: $ rm [options] file(s).
  • Example: $ rm file1.txt deletes a specified file.

Working with Directories

• Creating directories:

  • Use mkdir directory-name to create new directories (e.g., $ mkdir student).
  • Create multiple directories at once: $ mkdir student teacher administration.

• Change directories:

  • Use $ cd directory to navigate into a directory.
  • Use $ cd .. to go to the parent directory.
  • $ cd or $ cd ~ returns to the home directory.

• Display current directory:

  • Use pwd command to show the current working directory path.

Removing Directories

• Use rmdir to remove empty directories:
  • Example: $ rmdir student.
• To delete a directory and its contents, use:
  • $ rm -r directory_name (use cautiously).

Summary

• Mastering these commands enhances efficiency in managing files and directories on Linux.
• Familiarization with command-line syntax is crucial for effective use of the operating system.