Files and paths · Lesson 29 of 36 · 8 minutes

File type inspection

Identify files, directories, links, and text before acting on them.

Open the lab Course map

Mastery 0/3Run itExplain itApply it

learner@clairos:~ $

↑ history · Tab complete · Ctrl+C cancel · Esc, Tab to leaveExit 0

Your objectives

Hints are always available. Wrong turns never cost XP.

1
Identify a text file
Run file README.txt.
Hint & worked example
Identify a file from its characteristics rather than trusting only the filename extension.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
file README.txt
```
Remember: The simulator uses a small reviewed type classifier, not the full system magic database.
2
Identify a directory
Run file lab.
Hint & worked example
Identify a file from its characteristics rather than trusting only the filename extension.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
file lab
```
Remember: The simulator uses a small reviewed type classifier, not the full system magic database.
3
Compare detailed metadata
Run stat README.txt.
Hint & worked example
Inspect a file or directory metadata record, including ownership, permissions, and size.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
stat README.txt
```
Remember: Metadata and file contents answer different questions.

Understand the pattern

Identifying filesystem object types helps operators explain what they know before they change anything.

file: Identify a file from its characteristics rather than trusting only the filename extension.
The simulator uses a small reviewed type classifier, not the full system magic database.
stat: Inspect a file or directory metadata record, including ownership, permissions, and size.
Metadata and file contents answer different questions.

Worked example and expected result

$ file README.txt

/home/learner/README.txt: ASCII text

Exit status: 0. The command completed successfully in the training fixture.

$ file lab

/home/learner/lab: directory

Exit status: 0. The command completed successfully in the training fixture.

$ stat README.txt

Path: /home/learner/README.txt
Type: file
Mode: -rw-r--r--
Owner: learner
Group: learners
Size: 148 bytes

Exit status: 0. The command completed successfully in the training fixture.

Try a variation

Repeat this workflow in the sandbox with a different scratch filename. Keep the system fixtures unchanged and compare the observed output with your expectation before moving on.

Explain it

In “File type inspection”, which interpretation is safe?The simulator uses a small reviewed type classifier, not the full system magic database.A command appearing in history proves it completed successfully.A successful first check guarantees that every dependent service is healthy.

Apply it elsewhere

Before adapting the file workflow from “File type inspection” to another server, what should you do?Paste the training paths unchanged into production.Skip output inspection whenever the command is familiar.Confirm the current directory, target identity, permissions, and the installed command behavior first.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Canonical path review Try an incident drill

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