C++ rules for special member functions

C++ has several special member functions that are defined by the compiler even if not defined by the user. These special member functions are the default constructor, the copy constructor, the copy assignment operator, the move constructor, the move assignment operator, and the destructor. However, there are many rules for what is defined and in which circumstances. For instance, if no special member function is defined by the user then all of them are implicitly defined by the compiler. On the other hand, if a copy constructor or copy assignment operator is defined by the user, then the move constructor and move assignment operator are not defined by the compiler. To make it easier to comprehend all the rules, the following table describes what is defined by the compiler based on what is defined by the user.

Dining philosophers in C++11: Chandy-Misra algorithm

In my previous post, Dining Philosophers in C++11, I have provided an implementation for the dining philosophers problem using modern C++ features, such as threads and mutexes. However, it was noted in the comments that the implementation did not prevent the philosophers starving to death when you remove the waiting times. An algorithm that prevents…

Dining Philosophers in C++11

UPDATE: for an implementation of the Chandy/Misra solution see Dining philosophers in C++11: Chandy-Misra algorithm The problem of the dining philosophers, first proposed by Edsger Dijkstra and reformulated by Tony Hoare, is a famous problem for concurrent programming that illustrates problems with synchronizing access to data. The description of the problem, taken from Wikipedia, is…

MFC Collection Utilities library

This project has been moved to GitHub. New location: https://github.com/mariusbancila/mfccollectionutilities C++11 has provided support for range-based for loops. They allow iterating over the elements of a range without using an index.

However, if you try the following MFC code you get some errors because the compiler is looking for a begin() and end() function…

cppconlib: A C++ library for working with the Windows console

This project has been moved to GitHub. New location: https://github.com/mariusbancila/cppconlib Many years ago I published on my blog a helper class for working with the Windows console that was wrapping the Windows console API. Looking back at it I realized it was a pretty naive implementation. So I decided to start a new and make…

Beware of parallelization

A recent question on stackoverflow raised the problem of a fast algorithm to count the unique colors in an image (Faster algorithm to check the colors in a image). My answer what that this kind of problems are suited for parallelization. However, parallelization may only help when used judiciously. To demonstrate the point I have…

UNICODE support in the C++ Standard

The Oxford meeting of the ISO C++ standards committee between 15-20 April resulted in new features beeing into the draft paper of the C++0x standard. One of the features refer to Unicode support: a new header, called <cuchar>, was introduced. This header makes available new built-in types char16_t and char32_t, as well as new prefixes…