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    SubjectRe: If not readdir() then what?
    On Thu, 12 Apr 2007, Neil Brown wrote:

    > For the second.
    > You say that you " would need at least 96 bits in order to make that
    > guarantee; 64 bits of hash, plus a 32-bit count value in the hash
    > collision chain". I think 96 is a bit greedy. Surely 48 bits of
    > hash and 16 bits of collision-chain-position would plenty. You would
    > need 65537 entries before a collision was even possible, and
    > billions before it was at all likely. (How big does a set of 48bit
    > numbers have to get before the probability that "No subset of 65536
    > numbers are all the same" drops below 0.95?)

    Neil,
    you can get a hash collision with two entries.

    David Lang
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