An application in this case was made to a justice of the Supreme Court for a rule to show cause why a mandamus should not issue directed to the building inspector of the town of Westfield, compelling him to issue a permit to the relators to build a brick and concrete block extension to their dwelling at No. 656 West Broad street, such extension to be used as a store, in violation of the zoning ordinance of the district zone, in which the property is situated. The rule was denied, hence, an application to the court in banc. Pamph. L. 1927, p. 396, does not prevent this application from being made, that statute has no application. It would serve no useful purpose to pursue the argument of the relators through all the points argued in the brief; suffice it to say, we think the rule should be denied. The writ of mandamus is discretionary. Silvester v. Mayor, &c., of Princeton, 104 N. J. L. 18. It is never issued, where the legal right of the relator is in doubt or unsettled. Erion v. Pension Commission, 104 N. J. L. 464. The case of Kaslovisky v. Castles, 6 N. J. Mis. R. 599, is an authority for denying the rule. The application for a rule to show cause is therefore denied, with costs.