Inodes concept in Linux CLI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the command to list files with their inode numbers.

Linux CLI

ls -i [1]

Drag options to blanks, or click blank then click option'

A-a

B-l

C-h

D-R

Attempts:

3 left

💡 Hint

Common Mistakes

Using -l only shows detailed info but not hidden files.

Using -h is for human-readable sizes, not inode listing.

The -a option shows all files including hidden ones, which helps see all inodes.

2fill in blank

medium

Complete the command to find the inode number of a file named 'example.txt'.

Linux CLI

ls -i [1]

Drag options to blanks, or click blank then click option'

Aexample.txt

B-l example.txt

C-R example.txt

D-a example.txt

Attempts:

3 left

💡 Hint

Common Mistakes

Adding -l or -a unnecessarily.

Using recursive -R when not needed.

To find the inode of a specific file, just provide its name after ls -i.

3fill in blank

hard

Fix the error in the command to display inode numbers of all files in the current directory.

Linux CLI

ls [1]

Drag options to blanks, or click blank then click option'

A-l

B-i

C-a

D-h

Attempts:

3 left

💡 Hint

Common Mistakes

Using -l shows details but not inode numbers.

Using -h is for sizes, not inodes.

The -i option tells ls to show inode numbers.

4fill in blank

hard

Fill both blanks to create a command that finds files with inode number 123456.

Linux CLI

find . -inum [1] -print[2]

Drag options to blanks, or click blank then click option'

A123456

B > output.txt

C 2>/dev/null

D -type f

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong inode number.

Not redirecting output when needed.

The -inum option finds files by inode number. Redirecting output with > output.txt saves results.

5fill in blank

hard

Fill all three blanks to create a command that lists inode numbers, file sizes, and names for all files.

Linux CLI

ls [1] [2] [3]

Drag options to blanks, or click blank then click option'

A-i

B-l

C-a

D-h

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting -i so no inode numbers show.

Forgetting -h makes sizes easier to read.

-i shows inode numbers, -l shows detailed info including size, and -h makes sizes human-readable.

Practice

1. What does an inode in a Linux file system primarily store?

easy

A. The path to the file's location

B. The file name and its extension

C. Metadata about a file like permissions and size

D. The content of the file

Solution

1. Step 1: Understand inode purpose

   An inode stores metadata such as file permissions, ownership, size, and timestamps, but not the file name.

2. Step 2: Differentiate inode from file name storage

   The file name is stored separately in directory entries, not in the inode itself.

3. Final Answer:

   Metadata about a file like permissions and size -> Option C

4. Quick Check:

   Inode = Metadata [OK]

Hint: Inodes store file info, not names or content [OK]

Common Mistakes:

• Thinking inode stores file names
• Confusing inode with file content
• Assuming inode stores file path

2. Which command correctly shows the inode number of files in a directory?

easy

A. ls -i

B. ls -l

C. ls -a

D. ls -h

Solution

1. Step 1: Recall ls command options

   The ls -i command lists files with their inode numbers.

2. Step 2: Verify other options

   ls -l shows detailed info without inode, ls -a shows hidden files, ls -h shows sizes in human-readable form.

3. Final Answer:

   ls -i -> Option A

4. Quick Check:

   ls -i = inode numbers [OK]

Hint: Use ls -i to see inode numbers quickly [OK]

Common Mistakes:

• Using ls -l expecting inode numbers
• Confusing ls -a with inode display
• Trying ls -h for inode info

3. Given the output of ls -i shows two files with the same inode number, what does this indicate?

medium

A. The files are hard links pointing to the same data

B. The files have identical names

C. The files are located in different directories

D. The files are symbolic links

Solution

1. Step 1: Understand inode sharing

   Two files with the same inode number mean they share the same data on disk, which happens with hard links.

2. Step 2: Differentiate link types

   Symbolic links have different inodes; identical names or directories don't affect inode numbers.

3. Final Answer:

   The files are hard links pointing to the same data -> Option A

4. Quick Check:

   Same inode = hard links [OK]

Hint: Same inode means hard links share data [OK]

Common Mistakes:

• Confusing symbolic links with hard links
• Assuming same inode means same name
• Ignoring inode uniqueness

4. You run ls -i but get an error: ls: invalid option -- 'i'. What is the likely cause?

medium

A. Not having permission to list files

B. Using a non-Linux system where ls lacks -i option

C. Typing the command incorrectly as ls -l

D. The directory is empty

Solution

1. Step 1: Analyze error message

   The error says invalid option -- 'i', meaning the ls command does not recognize -i.

2. Step 2: Identify environment cause

   This often happens on non-Linux systems (like some Unix variants) where ls lacks the -i option.

3. Final Answer:

   Using a non-Linux system where ls lacks -i option -> Option B

4. Quick Check:

   Invalid option = unsupported ls -i [OK]

Hint: Check OS if ls -i option fails [OK]

Common Mistakes:

• Assuming typo in command
• Thinking permission causes option error
• Assuming empty directory causes option error

5. You want to find all files in a directory that share the same inode number (hard links). Which command pipeline helps you identify these files?

hard

A. find . -type l

B. ls -i | sort | uniq -d

C. ls -l | grep '^d'

D. ls -i | cut -d' ' -f1 | sort | uniq -d

Solution

1. Step 1: Extract inode numbers from ls -i output

   The inode number is the first field in ls -i output, so use cut -d' ' -f1 to get it.

2. Step 2: Find duplicate inode numbers

   Sorting and using uniq -d lists inode numbers that appear more than once, indicating hard links.

3. Final Answer:

   ls -i | cut -d' ' -f1 | sort | uniq -d -> Option D

4. Quick Check:

   Duplicate inodes = hard links [OK]

Hint: Extract inode field then find duplicates [OK]

Common Mistakes:

• Using uniq -d without extracting inode field
• Confusing symbolic links with hard links
• Using find for symbolic links instead