ChorusOS 4.0 Introduction

Static and Dynamic Linking

The following table summarizes the actions performed by the static linker, which runs on the development host, and by the runtime linker, which runs on the target.

Link	Relocatable Executable	Dynamic executable
Static Linker	`.a` Static linker adds necessary objects (`.o`) of a static library (`.a`) to the executable.	`.a` Static linker adds necessary objects (`.o`) of a static library (`.a`) to the executable. `.so` Static linker adds the library to the list of libraries to load at actor start-up (`afexec`).
Runtime Linker (`afexec`)	-	`.so` At actor start-up, libraries are loaded and linked by the runtime linker. Libraries to load are defined either at static link, or in the `LD_PRELOAD` environment variable. The runtime linker uses a library search path to find dynamic and shared libraries.
Runtime Linker (`dlopen`)	-	`.so` Application explicitly asks the runtime linker to dynamically load and link a dynamic library, using the `dlopen()` function of the dynamic linking API.

Dynamic linking of libraries applies recursively to library dependencies: when a library is loaded, all the libraries it uses are also loaded.