Виктор Таран, оч. жаль =(, я даже эксперимент провёл
архивируем: zip -r -s 100k archive.zip file
на выходе файлы: archive.zip, archive.z01, archive.z02, archive.z03...
пробуем
unzip archive.zip
Archive: archive.zip
warning [archive.zip]: zipfile claims to be last disk of a multi-part archive;
attempting to process anyway, assuming all parts have been concatenated
together in order. Expect "errors" and warnings...true multi-part support
doesn't exist yet (coming soon).
file #1: bad zipfile offset (local header sig): 4
после склеивания: zip -s 0 archive.zip --out summary.zip
unzip summary.zip норм распаковывает