cd (change directory) in Linux CLI - Step-by-Step Execution

Concept Flow - cd (change directory)

Start in current directory

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User types 'cd <path>'

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Shell checks if <path> exists and is directory

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Update current directory

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Prompt ready in new directory

The shell changes the current directory if the given path exists; otherwise, it shows an error.

Execution Sample

Linux CLI

pwd
cd /tmp
pwd
cd nonexistent
pwd

Shows current directory, changes to /tmp, shows new directory, tries to change to a non-existent directory, then shows directory again.

Execution Table

Step	Command	Condition	Action	Output
1	pwd	N/A	Print current directory	/home/user
2	cd /tmp	Does /tmp exist?	Yes, change directory to /tmp
3	pwd	N/A	Print current directory	/tmp
4	cd nonexistent	Does 'nonexistent' exist?	No, show error	bash: cd: nonexistent: No such file or directory
5	pwd	N/A	Print current directory	/tmp

💡 Execution stops after last pwd command showing current directory remains /tmp because cd to nonexistent failed.

Variable Tracker

Variable	Start	After Step 2	After Step 4	Final
current_directory	/home/user	/tmp	/tmp	/tmp

Key Moments - 2 Insights

Why does the current directory not change after trying to cd to a non-existent directory?

Because the shell checks if the directory exists before changing. Step 4 in the execution_table shows the condition fails and an error is printed, so the directory stays the same.

What happens if you just type 'cd' without any path?

The shell changes to your home directory. This is a shortcut not shown in the table but is a common behavior.

Visual Quiz - 3 Questions

Look at the execution_table, what is the current directory after step 3?

A nonexistent

B /home/user

C /tmp

D /

💡 Hint

Check the output column at step 3 in execution_table.

At which step does the shell show an error message?

A Step 2

B Step 4

C Step 5

D Step 1

💡 Hint

Look for the row with an error message in the Output column.

If the directory '/tmp' did not exist, what would happen at step 2?

A Show an error and keep current directory

B Change directory to /tmp anyway

C Create /tmp directory automatically

D Exit the shell

💡 Hint

Refer to the condition and action columns in execution_table for step 2 and 4.

Concept Snapshot

cd command changes the current directory.
Syntax: cd [path]
If path exists and is directory, shell moves there.
If no path, goes to home directory.
If path invalid, shows error and stays put.

Full Transcript

The cd command changes your current folder in the shell. When you type cd followed by a path, the shell checks if that folder exists. If it does, it moves you there. If not, it shows an error and keeps you where you are. For example, starting in /home/user, typing cd /tmp moves you to /tmp. Trying cd nonexistent shows an error and you stay in /tmp. Typing pwd shows your current folder at any time.