Presumably you're already using Digest, since this is apparently a followup to the thread file comparison using file open in binary mode.. In the Digest documentation there is a comparison of various digest speeds, with MD4 being the fastest.

If speed is really a huge deal, you could add an additional comparison stage, like perhaps an MD5 over only the first 64K of each file. Then if those match, do an MD5 over the whole file.

In reply to Re: MD5 Hash by gmargo
in thread MD5 Hash by Karger78

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