Actually, if the data for a current run produces the same SHA1 hash string (or the same MD5 signature, if one prefers) as some other file that already exists, wouldn't that mean that the existing file already contains exactly the same data as the current run? In that case, you have a built-in means to decide when a new file doesn't need to be written to disk (because the data in question are already there).

In reply to Re: Re: Automatically creating incremental file names by graff
in thread Automatically creating incremental file names by Anonymous Monk

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