problems with spin buttons

[Stoyan karanfilov <kasoftnew yahoo com>]

 Hi, I am writting an application, in which I have an
objecht, with cordinates x, y, z. I want when I click
on the arrow on the spin button to change this values,
and to start a function that moves the object. I'made
3 spin buttons with appropriate adjustments for this
purpose. But I don't know what what gtk function to
use to catch this event. Can you help me to do this?
I've allready tryed something like this: 
for (int i = 0; i < 3; i++){  
curr_pos [i] = gtk_spin_button_get_value
(GTK_SPIN_BUTTON (pspin[i])); 
} 
move_function (curr_pos [0], curr_pos [1], curr_pos
[2] );  

where pspin [] is: 
GtkWidget *pspin[3]; 
and curr_pos is: 
gdouble curr_pos [3];  

It does not seemed to work. I got segmentation fault.
There is something missing.. I'll be very gratefull if
you give me some advice how to wtite this. 
Thank you in advance! 
Stoyan.

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