wget for file downloads in Linux CLI - Mini Project: Build & Apply

Downloading Files Using wget

📖 Scenario: You want to download files from the internet to your computer using the command line. This is useful when you need to get documents, images, or software quickly without opening a browser.

🎯 Goal: Learn how to use the wget command to download files from a URL and save them with a specific name.

📋 What You'll Learn

Use the wget command to download files

Specify the URL to download from

Save the downloaded file with a custom name

💡 Why This Matters

🌍 Real World

Downloading files from the internet quickly using the command line is common for software installation, data collection, and automation tasks.

💼 Career

Knowing how to use wget helps in system administration, data science, and development roles where automated file downloads are needed.

1

Set the URL to download

Create a variable called file_url and set it to the exact URL https://example.com/sample.txt.

Linux CLI

# Create a variable called file_url with the URL
# Your code here

Hint

Use the syntax variable=value without spaces for shell variables. Quotes are recommended for URLs.

2

Set the output file name

Create a variable called output_file and set it to the exact filename downloaded_sample.txt.

Linux CLI

file_url="https://example.com/sample.txt"
# Create a variable called output_file with the filename
# Your code here

Hint

Remember to assign the filename as a string with quotes in shell variables.

3

Download the file using wget

Use the wget command with the -O option to download the file from $file_url and save it as $output_file.

Linux CLI

file_url="https://example.com/sample.txt"
output_file="downloaded_sample.txt"
# Use wget with -O to download the file
# Your code here

Hint

The -O option lets you specify the output filename.

4

Verify the downloaded file

Use the ls command to list the file named $output_file and confirm it exists.

Linux CLI

file_url="https://example.com/sample.txt"
output_file="downloaded_sample.txt"
wget -O "$output_file" "$file_url"
# List the downloaded file
# Your code here

Hint

The ls command shows files in the current folder.

Practice

1. What is the primary purpose of the wget command in Linux?

easy

A. To download files from the internet

B. To upload files to a server

C. To list files in a directory

D. To edit text files

Solution

1. Step 1: Understand the function of wget

   The wget command is designed to retrieve files from the internet using HTTP, HTTPS, or FTP protocols.

2. Step 2: Compare options with wget's purpose

   Uploading files, listing directories, or editing text are not functions of wget. It only downloads files.

3. Final Answer:

   To download files from the internet -> Option A

4. Quick Check:

   wget downloads files [OK]

Hint: Remember: wget = get files from web [OK]

Common Mistakes:

• Confusing wget with upload commands like scp
• Thinking wget edits or lists files
• Assuming wget is for local file operations

2. Which of the following is the correct syntax to download a file from http://example.com/file.txt using wget?

easy

A. wget -d http://example.com/file.txt

B. wget http://example.com/file.txt

C. wget download http://example.com/file.txt

D. wget -save http://example.com/file.txt

Solution

1. Step 1: Recall basic wget syntax

   The basic command to download a file is simply wget URL without extra flags.

2. Step 2: Analyze each option

   wget -d http://example.com/file.txt uses an invalid flag -d. wget download http://example.com/file.txt adds an unnecessary word download. wget -save http://example.com/file.txt uses a non-existent flag -save. Only wget http://example.com/file.txt is correct.

3. Final Answer:

   wget http://example.com/file.txt -> Option B

4. Quick Check:

   Basic wget syntax = wget URL [OK]

Hint: Use just 'wget' plus URL to download [OK]

Common Mistakes:

• Adding extra words or flags not supported by wget
• Using incorrect or made-up options
• Confusing wget syntax with other commands

3. What will be the output filename when you run wget http://example.com/data.csv in your current directory?

medium

A. index.html

B. downloaded_file

C. http://example.com/data.csv

D. data.csv

Solution

1. Step 1: Understand wget default naming

   By default, wget saves the downloaded file with the same name as in the URL's last part, here data.csv.

2. Step 2: Check other options

   index.html is default for HTML pages without filename. http://example.com/data.csv is invalid as wget does not save with full URL as filename. downloaded_file is arbitrary and not default.

3. Final Answer:

   data.csv -> Option D

4. Quick Check:

   Filename = last URL part = data.csv [OK]

Hint: Filename defaults to last part of URL [OK]

Common Mistakes:

• Expecting wget to rename files automatically
• Confusing default HTML save name with other files
• Thinking wget saves full URL as filename

4. You run wget -c http://example.com/bigfile.zip but it restarts download from zero instead of resuming. What is the likely cause?

medium

A. The URL is incorrect

B. You forgot to add the -r option

C. The server does not support resuming downloads

D. wget cannot download zip files

Solution

1. Step 1: Understand -c option in wget

   The -c option tells wget to continue/resume an interrupted download if the server supports it.

2. Step 2: Identify why resume fails

   If the server does not support partial content requests, wget cannot resume and restarts from zero. Other options or file types do not affect this behavior.

3. Final Answer:

   The server does not support resuming downloads -> Option C

4. Quick Check:

   -c needs server support [OK]

Hint: Resume needs server support, else restart [OK]

Common Mistakes:

• Thinking -r is for resume (it's for recursive)
• Assuming wget can't download zip files
• Blaming URL without checking server features

5. You want to download multiple files listed in urls.txt using wget, saving each with its original name. Which command correctly does this?

hard

A. wget -i urls.txt

B. wget -o urls.txt

C. wget --save-urls urls.txt

D. wget -c urls.txt

Solution

1. Step 1: Understand wget options for multiple downloads

   The -i option tells wget to read URLs from a file and download each one.

2. Step 2: Check other options

   -o is for log file output, not URLs. --save-urls is not a valid option. -c is for resuming downloads, not reading URL lists.

3. Final Answer:

   wget -i urls.txt -> Option A

4. Quick Check:

   Use -i to read URLs from file [OK]

Hint: Use -i to download from URL list file [OK]

Common Mistakes:

• Using -o instead of -i for input file
• Assuming -c reads URL lists
• Trying non-existent options like --save-urls