Hi Christian,

Christian Schlichtherle wrote:

> I am looking into integrating LZMA compression to my TrueZIP Driver Zip
> <http://truezip.java.net/truezip-driver/truezip-driver-zip/index.html>  as
> explained in the ZIP File Format Specification
> <http://www.pkware.com/documents/casestudies/APPNOTE.TXT> . Now I wonder
> what I need to do to restrict the compression to LZMA-only, not LZMA2 or XZ,
> or if I should not restrict it at all because supporting method 14 (LZMA)
> may imply supporting LZMA2 or XZ, too.

It is referring to LZMA1.  Some details:

 - The version information header refers to the version of Igor
   Pavlov's LZMA SDK used to compress (one byte major, one byte
   minor).  The LZMA SDK never used versions in the range [5, 8], so
   maybe some lie like "5.0" would be appropriate. ;-)

 - The uncompressed size of a stream is stored elsewhere in the ZIP
   file, so it is not included after the Properties header like it
   would be in the lzma_alone format.

 - I am not sure if the constraints on compression parameters
   mentioned at [1] would ever trip in decompressing ZIP files.
   Probably not in practice.  The spec doesn't mention them, alas.

Thanks,
Jonathan

[1] http://sourceforge.net/projects/lzmautils/forums/forum/708858/topic/2076918

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