As per Apple Documentation,
A dispatch semaphore is an efficient implementation of a traditional counting semaphore. Dispatch semaphores call down to the kernel only when the calling thread needs to be blocked. If the calling semaphore does not need to block, no kernel call is made.
Continue reading “Using data semphores in iOS (Synchronous Request)”
With the introduction to a new programming language known as SWIFT in the past year by the biggest technical giants Apple Inc, most dominant player in the mobile market, a new stage was set for developers to come up with more. I will agree that Swift is an easier platform to learn for all the developers though specially who are new to iOS development platform but shifting from Obj-C is not easy particularly not using the (*) pointer notation [Just kidding..].
Even if you are new to iOS there are lot of concepts that are not so friendly to understand and pretty much creates a confusion while learning and using the language basics.
One of most limbo concept is Optionals. It took me really good time to understand what it is all about specially when I was coming from the Obj-C background.
As it is said, there are 2 sides of the coin. Here to its has pros as well as cons. On the cons, the highly relative term is complexity. Trust me if you do not understand why ? or ! operators are used you will land in dead zone.
Let’s start with the basics.
Continue reading “Swift – Optionals”