all.
I'm using a 3rd party lib to archive/decompress some files. Input/output format is .zip.
But I've discovered that the lib could read well archives created with WinRAR, but cannot read archives created with 7-zip.
Could anyone tell me what the problem is and how it could be fixed.
hex view of starting of archive, created with winRar:
50 4b 03 04 14 00 00 00 08 00 EC 88 25 45 6e 1a ....
hex view of starting of archive, created with 7-zip:
50 4b 03 04 14 00 00 00 08 00 ED 88 25 45 6e 1a ....
the difference is in byte EC and ED.
7-Zip archives can be created using several different compression formats which are not compatible with standard ZIP compression/decompression libraries based for example on Info-ZIP source code.
Applications like WinRAR and Total Commander supporting creation/extraction of ZIP files natively use therefore additionally a DLL for extracting files from non standard 7-Zip archives.
See question Can I use the EXE or DLL files from 7-Zip in a Commercial Application? on FAQ page of 7-Zip.