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pythonzipcompressionzlibdeflate

ZIP files in the wild that don't use DEFLATE?


I'm making a (streaming) unZIP function in Python. ZIP files can use a range of compression algorithms, but the most common is DEFLATE according to https://en.wikipedia.org/wiki/ZIP_(file_format)

Are there any examples "in the wild" of ZIP files that don't use DEFLATE (say, on sites that offer downloads)? Both for testing, but also, I'm trying to work out whether it's worth adding this support.


Solution

  • I have read that Windows Explorer will create zip files using Deflate64 for entries greater than 2 GB. 7-Zip can, on request, generate zip files using Deflate64, BZip2, LZMA, or PPMd.

    I have not found anything in the wild that is not stored or deflated (at least in the last 30 years). But I haven't looked very hard either.