Files and paths · Lesson 30 of 36 · 8 minutes

Canonical path review

Turn relative and linked paths into stable absolute locations.

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
Resolve README
Run realpath README.txt.
Hint & worked example
Resolve a path to its canonical location in the virtual filesystem.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
realpath README.txt
```
Remember: Resolving a path and reading its contents are separate operations.
2
Resolve an absolute path
Run realpath /etc/nginx/sites-enabled/learn.conf.
Hint & worked example
Resolve a path to its canonical location in the virtual filesystem.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
realpath /etc/nginx/sites-enabled/learn.conf
```
Remember: Resolving a path and reading its contents are separate operations.
3
Compare the working directory
Run pwd.
Hint & worked example
Print the directory that relative paths currently resolve from.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
pwd
```
Remember: A relative path is interpreted from the working directory, not necessarily the home folder.

Understand the pattern

Resolving canonical filesystem paths helps operators explain what they know before they change anything.

realpath: Resolve a path to its canonical location in the virtual filesystem.
Resolving a path and reading its contents are separate operations.
pwd: Print the directory that relative paths currently resolve from.
A relative path is interpreted from the working directory, not necessarily the home folder.

Worked example and expected result

$ realpath README.txt

/home/learner/README.txt

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

$ realpath /etc/nginx/sites-enabled/learn.conf

/etc/nginx/sites-enabled/learn.conf

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

$ pwd

/home/learner

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 “Canonical path review”, which interpretation is safe?A command appearing in history proves it completed successfully.A successful first check guarantees that every dependent service is healthy.Resolving a path and reading its contents are separate operations.

Apply it elsewhere

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

Keep the momentum.

Complete the lab, then explain and apply the pattern.

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