HTTP requests with curl in scripts in Bash Scripting - Time & Space Complexity

Time Complexity: HTTP requests with curl in scripts

O(n)

Understanding Time Complexity

When running HTTP requests in a script, it is important to understand how the time to complete grows as you make more requests.

We want to know how the script's running time changes when the number of curl requests increases.

Scenario Under Consideration

Analyze the time complexity of the following code snippet.

for url in "$@"; do
  curl -s "$url" > /dev/null
  echo "Fetched $url"
done
    

This script takes a list of URLs and fetches each one using curl, printing a message after each fetch.

Identify Repeating Operations

Identify the loops, recursion, array traversals that repeat.

• Primary operation: The for-loop that runs curl for each URL.
• How many times: Once for each URL passed to the script.

How Execution Grows With Input

Each additional URL adds one more curl request, so the total time grows directly with the number of URLs.

Input Size (n)	Approx. Operations
10	10 curl requests
100	100 curl requests
1000	1000 curl requests

Pattern observation: The time grows linearly as you add more URLs.

Final Time Complexity

Time Complexity: O(n)

This means the total time increases in direct proportion to the number of URLs you fetch.

Common Mistake

[X] Wrong: "Running multiple curl commands in a loop happens instantly or all at once."

[OK] Correct: Each curl command waits for the server response before moving on, so the time adds up with each request.

Interview Connect

Understanding how loops with network calls grow helps you write efficient scripts and explain your reasoning clearly in interviews.

Self-Check

"What if we ran multiple curl requests in parallel instead of one after another? How would the time complexity change?"