PC name & user

[Pirulo Gomez]

I'm building a litle tool in C++ for make a lookup on my network. I need the samba "pc name" and "user" knowing only an ip. 
I try with the libsmbclient.h but I can't find documentation or know who to use it. I'm looking for something else than the smblookup (to slow and not always is installed), like a lib funtion or a shell call to do this. 

Can anybody help me? Thanks.