The ZZipLib Project does already provide THREE libraries. The classic zziplib.so (via "zzip/lib.h") is the most prominent one and used in a number of different projects. The zzipfseeko.so ("zzip/fseeko.html") and zzipmmapped.so ("zzip/mmapped.html") are technology demonstrations.
Additionally, there is a complete set of unpacked documentation - the unix manual pages are translated to html manual pages.