GtkPaned::set_handle_size
void set_handle_size(int size);
set_handle_size() can currently
be used to set the width or height of the handle in pixels. The
default setting is 5 pixels in the win32 binary, or 10 pixels in the
1.2.* series of GTK+. In GTK2 the size of the handle will be set at
5 pixels, across both platforms.
Please note that both this function and the
handle_size property are
deprecated in GTK2, and so should not be used.