X509_PURPOSE_get_id
i = X509_PURPOSE_get_id(xptmp);
id = X509_PURPOSE_get_id(pt);
int X509_PURPOSE_get_id(const X509_PURPOSE *);
&& TEST_int_eq(X509_PURPOSE_get_id(xp), id)
&& TEST_int_eq(X509_PURPOSE_get_id(xp), X509_PURPOSE_DEFAULT_ANY);