Passbook is one of the newest features of the iPhone. What many people were offput by standards today is that we rely too much on disposable tickets, and the like, such as when you go to the airport for a boarding pass, or a movie ticket. Apple strove to solve that with a new application that is bundled with the newest update: Passbook.

Passbook offers everything you need, especially when a ticket, coupon, or gift card is needed. When you first open the application you are greeted by a sampling of applications that support Passbook, and its features. To begin, install the particular application you want to use. For example, we will be going with the Starbucks application to satiate our coffee needs every morning, as we have a gift card to spend.

Open up the freshly downloaded application, and get ready to be blown away. Like most applications, especially when it has to do with airlines, or coffee, you are almost always required to sign up for a respective account. Don’t worry, it is easy. All you will be asked is to fill out your email, a password, and other miscellaneous information to identify you when you lose your password or others.

Once you have finished signing up, you’re ready to roll. It will prompt you to enter a gift card that you already own, or begin a digital gift card. If you don’t have a gift card, you can start a digital gift card (or, as many may call it: a prepaid card), and pay for your coffee in a fast, and efficient way. Just tap on “Tap to Pay” when you are ready to pay, and tap again after you have paid. It’s really that easy.

Memory management is always a priority in pretty much any programming language you would want to use. In the lower level languages such as C, there are a number of functions which help you manage the memory your application uses, but they are not the easiest to use. Some of the more modern programming languages such as Python, Ruby, Perl, and of course the subject of this article, Javascript all have a built in feature called garbage collection.

Garbage collection essentially means that the languages compiler will automatically free the memory being occupied by unused variables and objects, but there is no telling when this could occur. It is purely down to the compiler to decide when the garbage collection process should be initiated.

In programming, memory leaks are a common issue, and it occurs when a computer uses memory but does not give it back to the operating system. Experienced programmers have the ability to diagnose a leak based on the symptoms. Some believe every undesired increase in memory usage is a memory leak, but this is not an accurate representation of a leak. Certain leaks only run for a short time and are virtually undetectable.

Memory Leak Consequences

Applications that suffer severe memory leaks will eventually exceed the memory resulting in a severe slowdown or a termination of the application.

How to Protect Code from Memory Leaks?

Preventing memory leaks in the first place is more convenient than trying to locate the leak later. To do this, you can use defensive programming techniques such as smart pointers for C++.  A smart pointer is safer than a raw pointer because it provides augmented behavior that raw pointers do not have. This includes garbage collection and checking for nulls.

If you are going to use a raw pointer, avoid operations that are dangerous for specific contexts. This means pointer arithmetic and pointer copying. Smart pointers use a reference count for the object being referred to. Once the reference count reaches zero, the excess goes into garbage collection. The most commonly used smart pointer is shared_ptr from the TR1 extensions of the C++ standard library.

Static Analysis

The second approach to memory leaks is referred to as static analysis and attempts to detect errors in your source-code. CodeSonar is one of the effective tools for detection. It provides checkers for the Power of Ten coding rules, and it is especially competent at procedural analysis. However, some might find it lagging for bigger code bases.

How to Handle a Memory Leak

For some memory leaks, the only solution is to read through the code to find and correct the error. Another one of the common approaches to C++ is to use RAII, which an acronym for Resource Acquisition Is Initialization. This approach means associating scoped objects using the acquired resources, which automatically releases the resources when the objects are no longer within scope. RAII has the advantage of knowing when objects exist and when they do not. This gives it a distinct advantage over garbage collection. Regardless, RAII is not always recommended because some situations require ordinary pointers to manage raw memory and increase performance. Use it with caution.

The Most Serious Leaks

Urgency of a leak depends on the situation, and where the leak has occurred in the operating system. Additionally, it becomes more urgent if the leak occurs where the memory is limited such as in embedded systems and portable devices.

To protect code from memory leaks, people have to stay vigilant and avoid codes that could result in a leak. Memory leaks continue until someone turns the system off, which makes the memory available again, but the slow process of a leak can eventually prejudice a machine that normally runs correctly.

Related:

The Five Principles of Performance

In Demand IT Skills

Visual Studio .NET is one of many tools available at your disposal for web development. But where some programs may focus on HTML coding or graphics, Visual Studio .NET is a complete tool set that can be used to not only create XML web services and ASP web applications, but desktop and mobile applications as well. So what are some features that are included in the latest release?

·         Visual J#. This is most well-known by developers who are well-versed in the language of Java. It is best used when building services via the .NET framework, or when building applications.

·         Smart Device Applications. This enables you to generate, repair, and install applications that can be used on smart phones, PDAs, and other devices.

·         ASP.NET Mobile Design. Allows for building web applications for not only PDAs and mobile phones, but pagers as well. This also allows a designer to manipulate the mobile Web form of an application.