Install libopenthreads20 by entering the following commands in the terminal:
sudo apt update sudo apt install libopenthreads20
Description:
Object-Oriented (OO) thread interface for C++, shared libs
This library is intended to provide a minimal & complete Object-Oriented (OO) thread interface for C++ programmers, used primarily in OpenSceneGraph. It is loosely modeled on the Java thread API, and the POSIX Threads standards. . This package contains the shared libraries.
Homepage: http://www.openscenegraph.org/
Version: 3.2.3+dfsg1-2ubuntu8
Section: universe/libs