Where are the states defined for top?

It doesn't mention netio and I can't find any definition for it under
/usr/include or any man pages.

What is netio?

Thanks,

   Jeremy C. Reed

p.s. I am trying to stream ogg vorbis from NetBSD to Windows and it rarely
works. Sometimes top reprots "netio" state. FreeAmp under Windows hangs
every other time I use it.