GtkEntry and numeric floating point input

[Neil Zanella <nzanella gmail com>]

Hello,

I've got a GtkEntry and I need to confine user input into this widget
to numeric values
which will fit into the underlying C data types. What is the best way
to do this? If the
values were only allowed to be integers I'd use a GtkSpinBox (I think
that's what it's
called), but since they are now allowed to have decimal points etc...
what should I
do to be sure the user doesn't enter invalid data. What's the best way?

Thanks,

Neil