mkdir (create directories) in Linux CLI - Step-by-Step Execution

Concept Flow - mkdir (create directories)

Start

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Run mkdir command

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Check if directory exists

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Create directory

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End

The mkdir command tries to create a directory. If the directory exists, it shows an error unless options are used.

Execution Sample

Linux CLI

mkdir myfolder
mkdir myfolder
mkdir -p myfolder/subfolder

Creates a directory 'myfolder', tries to create it again (error), then creates 'myfolder/subfolder' with -p option.

Execution Table

Step	Command	Directory Exists?	Action Taken	Output
1	mkdir myfolder	No	Create 'myfolder'
2	mkdir myfolder	Yes	Error: directory exists	mkdir: cannot create directory ‘myfolder’: File exists
3	mkdir -p myfolder/subfolder	Yes (myfolder), No (subfolder)	Create 'subfolder' inside 'myfolder'

💡 After step 3, all directories exist; command ends successfully.

Variable Tracker

Directory	Start	After Step 1	After Step 2	After Step 3
myfolder	Does not exist	Exists	Exists	Exists
myfolder/subfolder	Does not exist	Does not exist	Does not exist	Exists

Key Moments - 2 Insights

Why does the second mkdir command give an error?

Because 'myfolder' already exists after step 1, so trying to create it again without -p causes an error (see step 2 in execution_table).

What does the -p option do in mkdir?

It creates parent directories as needed and does not error if the directory exists, allowing nested directories creation (see step 3).

Visual Quiz - 3 Questions

Look at the execution table, what is the output of step 2?

A No output, directory created

B Directory created with no error

C mkdir: cannot create directory ‘myfolder’: File exists

D Permission denied error

💡 Hint

Check the 'Output' column for step 2 in the execution_table.

At which step does 'myfolder/subfolder' get created?

A Step 2

B Step 3

C Step 1

D It is never created

💡 Hint

Look at the 'Directory Exists?' and 'Action Taken' columns for 'myfolder/subfolder' in the execution_table.

If we remove the -p option from step 3, what would happen?

A Error because 'myfolder/subfolder' parent missing

B Subfolder is created anyway

C Error because 'myfolder' does not exist

D No error, command ignored

💡 Hint

Without -p, mkdir cannot create nested directories if parents don't exist; see step 3 explanation.

Concept Snapshot

mkdir command creates directories.
If directory exists, mkdir errors unless -p option is used.
-p creates parent directories as needed.
Syntax: mkdir [options] directory_name
Use -p for nested directories without errors.

Full Transcript

The mkdir command is used to create directories in Linux. When you run mkdir with a directory name, it creates that directory if it does not exist. If the directory already exists, mkdir shows an error unless you use the -p option. The -p option allows creating nested directories and does not error if the directory exists. For example, running 'mkdir myfolder' creates a folder named myfolder. Running it again causes an error because the folder exists. Using 'mkdir -p myfolder/subfolder' creates the subfolder inside myfolder, creating any missing parent directories as needed.