Say I want my app to contact my server to check a serial, what's the easest way?

I was thinking of having it call a php page that checks the serial and returns a "ok" or a "bad", how would i go doing that? Any library I should use (preferably cross platform)? Is this easy or hard?

Btw I'm using C++

libcurl should do what you want. It's relatively easy.

Thanks... I'll see if i can get it working :/ (I suck at getting libraries working...)