Node.js · Middle · Question 17 of 75

What is the difference between `Buffer.alloc(10)` and `Buffer.allocUnsafe(10)`?

✓Correct answer: alloc fills memory with zeros; allocUnsafe is faster but may contain old data from memory
2allocUnsafe creates a buffer that can't be resized
3There is no difference

Explanation

Use allocUnsafe only if you immediately overwrite every byte. Otherwise you might leak sensitive data that was previously in that memory.

Further reading

Node.js API: Buffer ↗

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