flynn017

The SwishDbgExt library contains a number of interesting extensions which are imperative for deep debugging results. The SwishDbgExt library was written by Matt Suiche . Note: If you wish to use the ProcDumpExt DLL for WinDbg, and also view the help information for the extensions provided in SwishDbgExt, then you'll need to unload ProcDumpExt first since ProcDumpExt will overload the !help extension with it's own version. You can simply load ProcDumpExt again afterwards. Alternatively, if you do not wish to unload the ProcDumpExt DLL, then simply use the longhand method of !SwishDbgExt.help <SwishDbgExt Extension> . You must also omit the exclamation mark (!) from the extension name, otherwise the !help extension will not work. Note: You can use the .chain command to check if you have the ProcDumpExt DLL loaded or not. The .chain command will dump all loaded DLLs for the dump file. The available extensions from the DLL can be found by using the !SwishDbgExt.help ex...

This post is a little irrelevant to general contents of my blog, but I found this to be a interesting geometry problem and it does have some ties with Computational Geometry, which is form a of theoretical computer science. There is additionally some connection with Computational Complexity Theory too. The Bin Packing Problem isn't difficult to explain, and yet can be difficult to find a optimal solution. With Discrete Mathematics, I personally find that the branches within this field are more accessible but the problems are difficult enough to be interesting and form a field of serious mathematical study. I'm only a amateur mathematician and a student, so if there are any problems then please highlight them in the comments section. Bin Packing Problem: The Bin Packing Problem is an example of a optimization problem which has a surprisingly large number of applications, especially in logistics and data management. The Bin Packing Problem asks to minimize the number of bins need...

I thought I would create a list of Maths topics which were relevant for those who are wishing to study Computer Science. I've seen most people on online communities referring to topics which have very little relevance or completely pointless in relation to Computer Science. This list is based upon my experiences and a friend who studies Computer Science at University. I've listed the most popular Computer Science fields and their Maths topics below. General Computer Science: These are the topics which you will typically study in your first year, and therefore will have to do. Graph Theory Linear Algebra (Matrices and Vectors) Calculus I and maybe some Calculus II  Analytical Geometry Set Theory Big O Notation Radicals, Logarithms and Polynomials Logic Computer Graphics:  I'm not too sure about Graphics, but these are the subjects which do have some relevance. Fractal Geometry Linear Algebra Analytical Geometry Differentiable Geometry Hyperbolic Geometry Differential Equati...

Computers are increasingly being used to solve mathematical problems, and are becoming more prominent in solving problems in Number Theory and Graph Theory, as well as, fields of Physics and Biology. However, computers have been used to create seemingly random numbers for either games or security purposes; these seemingly random numbers are called Pseudo-Random. They may seem random but in fact they aren't random at all. To illustrate the difference between a true random number and a pseudo random number, look a look at the two images I've taken from Bo Allen's blog: True Random Number Pseudo Random Number The difference is very obvious and thus highlights the key differences between a true random generator and a pseudo random number generator. A pseudo random number generator uses a mathematical algorithm, which is able to produce seemingly random numbers. A true random number generator uses methods which can't be predicted, and therefore are truly random. The randomn...

Artificial Intelligence is both a topic of Computer Science and Philosophy, and begins to ask what really makes us human and if we are just a complex biological machine? Alan Turing first asked the question in his 1950 paper named Computing Machinery and Intelligence . The paper is much more accessible in comparison to his paper about Computability Theory and computable numbers, which are real numbers that can be calculated with a terminating algorithm, the computable numbers are also considered countable (number of axioms for this). This blog post won't be long, and I'll probably conclude with a link to my OneDrive account which has a copy of Alan Turing's paper. I'm going to be mostly be talking about the philosophy of Artificial Intelligence. There is one concept which has been of great interest to philosophers since the beginning of civilization, and that is the concept of consciousness, which is the ability to be able to be aware of our own existence. This concept ...

This is going to very loosely related to Programming and Computer Science I know, but I thought it was quite a interesting little simple programming project to do. I've written the code in C++, but you could easily adapt it to C or any other language if you so wish. The Fibonacci Number Series is a special sequence of numbers which is the sum of the two numbers before the current number. All the numbers will be integers (whole numbers). There is a simple mathematical equation for expressing this relationship: Our seed values, or starting numbers, are going to be 0 and 1. This can be seen with the variables shown in my code. The seed numbers have to be 0 and 1, or 1 and 1 in order for the above equation to work. I've commented the code, so it should be easier to understand, even though it is a simple program, the components would only really make sense if you understood the Fibonacci Number Series. The number of terms within the sequence can be selected by the user, and is then ...

Virtual Functions are a fundamental aspect of OOP programming features such as polymorphism. Any Virtual Functions are stored within a dispatch table called a VTable or Virtual Method Table. The VTable is essentially a array of virtual function pointers. It is possible to find the VTable using WinDbg, and I will demonstrate this within this blog post. Virtual Functions and Virtual Function Table Pointers I've written a very simple program using C++ to demonstrate the syntax of Virtual Functions. As you can see, there are two classes called A and B. A is the base class in which Class B will inherit any members or member functions from. By using the virtual keyword on the function in Class A called Function, it specifies that the function is a Virtual Function and not a standard function. When Class B inherits Class A's properties, then the Function is redefined within Class B which can be seen on Line 14. Please note this is not function overloading, since the function still ret...

Prerequisites:   - Knowledge of C/C++ - Knowledge of Calculus/Algebra Time Complexity and O(n) You could consider this topic as a Computer Science/Programming topic. However, I always consider Computer Science and Programming to be two different topics rather than the same thing, even though they both share the same programming principles, such as understanding how to write code to begin with. Computer Science is more like Applied Mathematics, and is more theory based, whereas, Programming is more practical and using a language or multiple languages as tools to create real-life programs. I've written a simple program which creates nodes within a linked list, and then walks this linked list when the user has decided they do not wish to insert any more nodes into the list. I've commented the code where necessary so it will be easier to understand. We'll then calculate the time complexity of the algorithm used to insert the nodes within the linked list. Firstly, let's con...

Memory Barriers in Code Memory Barriers are used to enforce some kind of ordering on how the compiler or CPU execute memory ordering operations. Since most CPUs have some form of technology which is used to optimize the execution of code, the problem of out-of-order execution can occur in programs leading to unpredictable results. Each variable or data structure we create is referred to as a an object, and each object has a memory address and memory address load order. This load order defines which variables are written to and loaded first. You probably will never notice this with program which has one thread, typically this is simply main. However, if you create two threads and have these two threads run concurrently, the question of which thread runs first raises? Although, we can add synchronization dispatcher objects to our code, the point of this blog post is to look at the concept of memory barriers and examine the Assembly code which is produced through binary analysis. In the M...

Splay Trees are an example of a binary search tree, which is a data structure for arranging and sorting data, which is sorted into nodes. They make good use of pointers. Splay Trees share the same structure as a standard binary search tree, but provide benefits such as the most accessed node always being the root or top of the tree. There three standard algorithms for splaying the node to the root of the tree, and these depend upon the positioning and depth of the node within the Splay Tree. Splay Trees are used in IFS (Installable File Systems). The length of the time taken to complete a algorithm for a Splay Tree, can be calculated with the Big O notation. There's no randomisation within Splay Trees, and therefore some operations can be expensive and time consuming, this is especially true when Splay Trees become unbalanced and very tall. It could take many Zig operations to splay a node to the root of the tree. Each rotation is called a Splay Step, and the process is called Spla...