HLLib is a package library for Half-Life that abstracts several package
formats and provides a simple interface for all of them.  HLLib is written
in native C++ but exposes both a C and C++ interfaces which can be used in
any C or C++ application (additional languages may also use the library with
standard C imports).  HLLib works natively in both Windows and *nix.  BSP,
GCF, NCF, PAK, VPK, WAD, XZP, and uncompressed ZIP package formats are
supported.

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