re: Do you have any idea how long your delimited chunk of data will be? If not, how about maximum and/or minimum lengths for it?

The minimum length (of what's between the two 4-byte endcaps) is only a couple bytes, I don't have my notes but it's a very small number, like maybe 5. The largest possible value is 128 bytes greater than that.

re: Once you find the chunk you are searching for, how will you differentiate it from any other delimited chunk included in this "arbitrary binary file?" I ask because if you have some criteria by which you can evaluate it as being the one you want, that might help you in the actual search.

OK, I'll go into more detail. Between the two endcaps, there will be another sequence of 3 or 4 specific bytes. Before that mark I expect 0-128 bytes of legal UTF-8 text. After that, the data also has internal format consistancies. Furthermore, the byte following the ending 4-byte delimiter is a hash "checksum" of the data block.

I consider a valid "hit" if the middle mark is present, there is no FE or FF bytes before that mark, and the checksum checks. (after I accept it, I decide if the other data values are any good)

Thanks;
—John

In reply to Re: Re: How do I search this binary file? by John M. Dlugosz
in thread How do I search this binary file? by John M. Dlugosz

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