nothing simple. your missing libs/headers or your setup is not correct. the things your missing like PCI_AGP_CMD are present, but your not getting them in the output you need because they are not being defined and included by correct compiler dependancies.

you dont seem to have the C knowledge to know how to fix things, and its not so simple to transmite over a forum message.

use extern theoretically, but it will not run without a library

Things became more clear. Some libs used in project may be compiled for dos/win9x/nt and compiler places underscore sign in front or at back of function names. Think I have to recompile some libs

The _name@xx notation means stdcall calling convention. This means the prototype of the function needs to have stdcall so the compiler will generate correct code.