What types of libraries do you know and what are their differences?

Types of libraries:

• Static libraries (.a in Linux, .lib in Windows): The library code is embedded directly into the application's executable during compilation. The application becomes larger in size but does not depend on the presence of the library itself at runtime. Each application using a static library has its own copy of the code.
• Dynamic (shared) libraries (.so in Linux, .dll in Windows): The library code is loaded into the application's memory at runtime. This reduces the size of the executable file. Multiple applications can use the same copy of the library, saving memory. For the application to work correctly, the dynamic library must be present in the system.

Main differences:

Attribute	Static library	Dynamic library
Application size	Larger (code embedded)	Smaller (code loaded at runtime)
Dependency	None (code inside the executable)	Present (library must be in the system)
Memory usage	Each application has its own copy of the code	Multiple applications can share one copy
Code update	Requires recompilation of the application	Can update the library separately

Example of using a static library in C++ (conditional):

// main.cpp
#include "static_library.h" // Header file of the static library

int main() {
  // Call function from static library
  static_function();
  return 0;
}

Example of using a dynamic library in C++ (conditional):

// main.cpp
#include <dlfcn.h> // For functions to load dynamic libraries

int main() {
  // Load dynamic library
  void* handle = dlopen("dynamic_library.so", RTLD_LAZY);
  if (!handle) {
    // Error handling
  }

  // Get address of function from library
  void (*dynamic_function)(void) = (void (*)(void))dlsym(handle, "dynamic_function");
  if (!dynamic_function) {
    // Error handling
  }

  // Call function
  dynamic_function();

  // Close library
  dlclose(handle);

  return 0;
}