Anatomy of Linux dynamic libraries

Dynamically linked shared libraries are an important aspect of GNU/Linux, as they allow executables to dynamically access external functionality at run time and thereby reduce their overall memory footprint (by bringing functionality in when it's needed). This article investigates the process of creating and using dynamic libraries, provides details on the various tools for exploring them, and explores how these libraries work under the hood.

Libraries were designed to package similar functionality in a single unit. These units could then be shared with other developers and permitted what came to be called modular programming—that is, building programs from modules. Linux supports two types of libraries, each with its own advantages and disadvantages. The static library contains functionality that is bound to a program statically at compile time. This differs from dynamic libraries, which are loaded when an application is loaded and binding occurs at run time.