Small question about GtkTextView

[Pavel Syomin <syomin radico ru>]

Hi, I'm try to create something like console widget using GtkTextView, 
but I'm confronted with some difficults. I want to process user input 
before change GtkTextBuffer, but don't know how to do it. For example, 
when user press "up arrow" or "down arrow" key I need to change current 
line in GtkTextBuffer and when user press "Enter" I need to call 
function. I read Gtk API reference, but didn't find answer for my 
question. Any ideas?