How to use libapt (or libept) in debian-like system to list packages and get their infos?

Question

Somebody used libapt or libept to list packages and get informations about package in a debian-like system?

Libapt is not well-documented at all, and i\'ve found few

Answer 1

Take a look at how apt-cache(8) is implemented. Obtaining the source with apt is easy:

# apt-get source apt

In the source file cmdline/apt-cache.cc theres is a function called DumpPackage() which extracts information from a named file in the cache.