The following method takes a ptr->BOOL. I've played around but cannot figure out how to create a pointer to a true/false that then returns true/false via its accessor. - (BOOL)fileExistsAtPath:(NSString *)path isDirectory:(BOOL *)isDirectory The following doesn't work: framework 'Cocoa' p1 = Pointer.new_with_type('@') p1.assign(false) p1[0] == false # => false, but should be true Then I figured I should be able to pass BOOL to -new_with_type as it is the data type, but BOOL isn't recognised. Perhaps test_objc.rb could include some more examples/coverage of Pointer usage too? -- Dr Nic Williams iPhone and Rails consultants - http://mocra.com Fun with iPhone/Ruby/Rails/Javascript - http://drnicwilliams.com * Surf Report for iPhone - http://mocra.com/projects/surfreport/ *