Node.js · Junior · Question 43 of 75

Why should you avoid `fs.readFileSync` inside an HTTP request handler?

1It works only on Windows
2It cannot read text files
✓Correct answer: It blocks the event loop, so no other request can be served until the file is read

Explanation

Sync calls are fine at startup (loading config) or in CLI scripts. In a server, use fs/promises or streams.

Further reading

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