Why? It seems to me that reading entire file to calculate its hashes is a waste of time compared to just reading the entire file.

Calculating hashes is useful in two circumstances: 1) When comparing one document to many (or many to many), 2) When a compact signature of the file is needed (for ease of communication or storage).

In reply to Re^2: Compare Binary Files by ikegami
in thread Compare Binary Files by drodinthe559

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