Well there are many zlib articles , tips and tutorials. Some of them are
1) Bobobobo’s Blog
This article basically tells you how to use zlib, and there is a snippet of code that will get you going.
This project shows you how to use zlib. Its
a console project, because there’s no
need to create a window to demonstrate
use of zlib.
2) zlib: Add Industrial Strength Compression to Your C/C++ Apps
For simplicity’s sake, this tutorial
covers only the basic C-style
interface. All the concepts inherent
there will be relevant to most other
bindings.
Since its in C language, it will be most beneficial to your requirements.
Last, you can use this too available in zlib. From the manual, Utility Functions:
ZEXTERN int ZEXPORT uncompress OF((Bytef *dest, uLongf *destLen,
const Bytef *source, uLong sourceLen));