Honestly you don't need an API to use the sockets API.
I am using the BSD sockets with GTK+ on Windows and Linux since a few years and it works great, code does exactly what I want and I like to have control over everything.
Portability is not a problem it's just a question of 2 or 3 pre-processor directives.
At the end your app does not depend on another third-party lib that implies updates.
Not to mention libs -although they are extremely well written- won't do exactly what you are looking for: this is particulary true when it comes to servers when you have to choose the right I/O model that fits your needs.
Using sockets is very simple plus code is short but well some might think it is easyer to learn a second API. Think long-term.
Regards,
Katsankat