What is the minimum distance required for the exile (taghrib) for a man?

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A man must be exiled to a distance equivalent to the minimum distance for shortening prayers (masafat al-qasr). This is because any distance less than that is considered to be within the ruling of a settled place (hadar), evidenced by the fact that the traveler's concessions (rukhsas) do not apply to him at such a short distance.