How to know is a buffer is a temporary one?

[Sebastien Vauban]

Hello,

I want to attach some code on first-change-hook, but I noticed *a lot* of
temporary buffers are created (and modified), hence my code running in many
situations where it doesn't need to.

So, is there a way for my code not to be applied for temp buffers? Function to
use in a `(when ...)' construct? Or do I have to look for the pattern `^ *' in
the name of the buffer (that is, a name beginning with a space and a star)?

Best regards,
  Seb

-- 
Sebastien Vauban