Order sustaining demurrer affirmed. The petitioner, a resident of Provincetown, seeks by certiorari to set the board of appeals of the town granting a variance to Patricia Phillips to operate a beauty shop in a residential district. The respondents’ demurrer was sustained. In arguing that certiorari should lie, the petitioner asserts that he is not a “person aggrieved” within the purview of G. L. c. 40A, § 21, and hence is not limited to the exclusive remedy in equity provided by that section. See Smith v. Board of Appeals of Plymouth, 340 Mass. 230, 232. Whether, in view of § 21, the remedy of certiorari is ever available to one challenging the decision of a board of appeals with respect to a zoning matter need not be decided. For present purposes it is enough to say that the demurrer was rightly sustained because the petitioner has failed to allege that the board’s decision has resulted or will result in substantial injury or manifest injustice to him. North Shore Corp. v. Selectmen of Topsfield, 322 Mass. 413, 418, and cases cited.