Terminal basics · Lesson 25 of 34 · 8 minutes

Command anatomy review

Separate a command name, its options, and its target before pressing Enter.

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Your objectives

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1
Read the ls manual
Run man ls.
Hint & worked example
Read a short built-in teaching reference for one supported command.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
man ls
```
Remember: For real administration, check the installed command manual and version too.
2
Locate ls
Run which ls.
Hint & worked example
Find the simulated executable path for a command.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
which ls
```
Remember: A path lookup does not prove that running the command will succeed.
3
Apply options to a listing
Run ls -la.
Hint & worked example
List directory entries; -a includes hidden names and -l adds ownership and permission detail.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
ls -la
```
Remember: A listing is not proof that you can read or modify every listed file.

Understand the pattern

Reading command names, options, and arguments helps operators explain what they know before they change anything.

man: Read a short built-in teaching reference for one supported command.
For real administration, check the installed command manual and version too.
which: Find the simulated executable path for a command.
A path lookup does not prove that running the command will succeed.
ls: List directory entries; -a includes hidden names and -l adds ownership and permission detail.
A listing is not proof that you can read or modify every listed file.

Worked example and expected result

$ man ls

LS(1)
NAME
  ls - list simulated directory contents
SYNOPSIS
  ls [-la] [path]
NOTE
  Use -a for hidden dotfiles and -l for metadata.

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

$ which ls

/bin/ls

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

$ ls -la

--rw-r--r-- learner learners   105 .profile
ddrwx------ learner learners   dir .ssh
ddrwxr-xr-x learner learners   dir archive
ddrwxr-x--- learner learners   dir backups
ddrwxr-xr-x learner learners   dir data
ddrwxr-xr-x learner learners   dir lab
ddrwxr-xr-x learner learners   dir notes
ddrwxr-xr-x learner learners   dir projects
--rw-r--r-- learner learners   148 README.txt
ddrwxr-x--- learner learners   dir restore
ddrwxr-xr-x learner learners   dir scripts

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 “Command anatomy review”, which interpretation is safe?A path lookup does not prove that running the command will succeed.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 which workflow from “Command anatomy review” 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: Option reading drill Try an incident drill

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