File download automation in Bash Scripting - Cheat Sheet & Quick Revision

Recall & Review

beginner

What command is commonly used in Bash to download files from the internet?

The curl command is commonly used to download files from the internet in Bash. Another popular command is wget.

beginner

How do you save a file with a specific name using curl?

Use the -o option followed by the desired filename. Example: curl -o myfile.txt https://example.com/file.txt saves the file as myfile.txt.

intermediate

What does the -L option do in curl?

The -L option tells curl to follow redirects. This is useful when the URL redirects to another location before the file is downloaded.

intermediate

How can you automate downloading multiple files in Bash?

You can use a loop to iterate over a list of URLs and download each file using curl or wget. For example, a for loop with URLs stored in an array.

beginner

Why is it helpful to check if a file already exists before downloading it in a script?

Checking if a file exists prevents unnecessary downloads, saves bandwidth, and avoids overwriting files. This makes the script more efficient and safer.

Which command option saves a downloaded file with a specific name using curl?

A -x

B -d

C -o

D -s

The -o option in curl specifies the output filename.

What does the -L option do in curl?

A Limits download speed

B Follows redirects

C Downloads in background

D Shows download progress

The -L option makes curl follow HTTP redirects automatically.

Which Bash structure is best for downloading multiple files automatically?

A case statement

B while loop

C if statement

D for loop

A for loop is commonly used to iterate over a list of URLs to download multiple files.

Why check if a file exists before downloading in a script?

A To avoid overwriting and save bandwidth

B To change file permissions

C To delete old files

D To speed up the download

Checking file existence avoids unnecessary downloads and prevents overwriting existing files.

Which command can also be used to download files besides curl?

A wget

B ls

C cat

D grep

wget is another popular command-line tool for downloading files.

Explain how you would write a Bash script to download a list of files from URLs stored in an array.

Think about looping through each URL and using curl with -o option.

Describe why following redirects is important when automating file downloads and how to enable it in curl.

Consider what happens if the file is moved to a new address.