cdp(...)
{
    integer e;
    record r;
    text s;

    ucall(r_add, 1, r, 0);

    if (~r) {
        s = r.low;
        s = s.cut(0, e = b_trace(s, prefix(s, r.high), '/'));
        s = ~s || e == -1 ? s : "/";
    }

    s;
}

main(void)
{
    o_(cdp("/home/user1/tmp/coverage/test",
           "/home/user1/tmp/covert/operator",
           "/home/user1/tmp/coven/members"), "\n");

    0;
}