Hotpatch is a library that can be used to dynamically load a shared library (.so) file on Linux from one process into another already running process, without affecting the execution of the target process. The API is a C API, but also supported in C++.
Hotpatch is BSD licensed.
The source code can be found here .
A compiled 32-bit package for Linux x86 is available as Hotpatch v0.2 32-bit
A compiled 64-bit package for Linux x86-64 is available as Hotpatch v0.2 64-bit