#include <kernwin.hpp> // For get_screen_ea() definition
#include <xref.hpp>

xrefblk_t xb;
ea_t addr = get_screen_ea();

// Get the first cross reference to addr
if (xb.first_to(addr, XREF_FAR))
{
    if (xb.next_to())
        msg("There are multiple references to %a\n", addr);
    else
        msg("The only reference to %a is at %a\n", addr, xb.from);
}