One of the significant advantages of a C++ string to a C string and of a std::vector to a C array is that both C++ containers automatically manage their memory. Of course, that holds for all further containers of the Standard Template Library. In this post, I will look closer at the automatic memory management […]
std::unique_ptr models the concept of exclusive ownership, std::shared_ptr the concept of shared ownership. If I stick to this picture then std::weak_ptr models the concept of temporary ownership because it borrows the resource from a std::shared_ptr. There is one dominant reason for having a std::weak_ptr in C++: breaking of cyclic references of std::shared_ptr‘s.
After I draw the big picture of a std::shared_ptr in the last post, I want to present two special aspects of this smart pointer in this post. First, I show with std::shared_from_this how to create a std::shared_ptr from an object; second, I’m interested in the question to the answer: Should a function take a std::shared_ptr […]
std::shared_ptr’s share the resource. The shared reference counter counts the number of owners. Copying a std::shared_ptr increases the reference count by one. Destroying a std::shared_ptr decreases the reference count by one. If the reference count becomes zero, the resource will automatically be released.
According to the RAII idiom, a std::unique_ptr manages automatically and exclusively the lifetime of its resource. std::unique_ptr should be your first choice because it does its work without memory or performance overhead.
C++11 offers four different smart pointers. I will have a closer look in this post regarding memory and performance overhead on two of them. My first candidate, std::unique_ptr takes care of the lifetime of one resource exclusively; std::shared_ptr shares the ownership of a resource with another std::shared_ptr. I will state the result of my tests […]
The careful handling of resources – may it be, for example, memory, files, or sockets – is a key concern of programming in C++. This holds, in particular, true for embedded programming, which is often characterized by limited resources. Therefore, I will write a few posts about this challenging and versatile topic.
Plain Old Data (POD) obeys the C standard layout. Therefore, you can directly apply the fast C functions memcopy, memmove, memset, or memcmp.
The hash function maps a potentially infinite number of keys on a finite number of buckets. What is the strategy of the C++ runtime and how can you tailor it to your needs, that is what this article is all about.
The hash function is responsible for the unordered associative containers’ constant access time (best cast). As ever, C++ offers many ways to adjust the behavior of the hash functions. On the one hand, C++ has a lot of different hash functions; on the other hand, you can define your hash function. You can even adjust […]