PostgreeSQL C header files

Hello,

at the moment I try to write a little CGI library written in C++. I want offer
a PostgreeSQL interface for all the user of my CGI library.
Is there any book or a good documentation how I use the C headerfiles Postgree
SQL hopefully offers?

I know, that Postgree SQL is written with C - so there should be C header
files - and perhaps there are C++ header files too.

With headerfiles I mean C/C++ functions/classes, which provide an easy use.

Thank you very much.

Christian Kienle
(I have already searched the PostgreeSQL hp and looked throw the documentation
- I found nothing ;(( )

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