vte_terminal_fork_command behavior

Hi!

I'm starting a little project and i need to include the vte widget in
my application. I haven't experience with this widget and i wrote a
little program only for testing and training and i'm seeing an strange
behavior depending on the command i run.

If I do
   vte_terminal_fork_command(w, "vim", NULL, NULL, ".", FALSE, FALSE, FALSE);

Vim is executed and i can interact with it. But if I run a program
like "ls", which ends after directory listing, no output is shown, no
matter what I do.

How I can show output of programs that ends? Is this behavior normal?

Thank you all in advance
ignacio