What is the test for an inmate to claim that his right of access to the courts has been violated?

^2. A prisoner claiming that his right of access to the courts has been violated must show that: 1) access was so limited as to be unreasonable, and 2) the inadequate access caused actual injury. Vandelft v. Moses, 31 F.3d 794, 797 (9th Cir. 1994). A prisoner cannot make conclusory declarations of injury, but instead must demonstrate that a non-frivolous legal claim has been frustrated or impeded. To prevail, however, it is not enough for an inmate to show some sort of denial. An "actual injury" is "actual prejudice with respect to contemplated or existing litigation, such as the inability to meet a filing deadline or to present a claim." Lewis, 518 U.S. at 348.