macOS Anyone know how to use C++/OpenGL/XWindows to create multiple windows (multithreading

I am trying to create a multithreaded (multiple windows) program using OpenGL 2.1 (with shaders). I do not want to use Glut because it is too high level and does not allow me control of events for multiple windows.

My difficulty is that when I created a project with OpenGL and XWindows - it worked fine with the OpenGL 1.2 calls, but when I tried to use the 2.1 OpenGL extensions, it failed.

For example, when I used the glCreateProgram method for creating a shader program, my app compiled fine and even linked fine - but at run time the method returned a 0 rather than a program handle.

Does anyone have any experience with using OpenGL 2.1 with XWindows?

Thanks

Yes, my video card has support for OpenGL 2+
I have been running a test app using shaders (and glut) just fine (using glut).
The problem is that glut is limited in how it handles messages coming in from multiple windows simultaneously. I need to create my own message loop, rather than using glut's, to get the multithreaded capabilities,
The XWindows framework will allow me to do what I want, but it does not seem to want to play well with OpenGL and the shader extensions.

I cannot seem to figure out how to get the right versions of the libraries to compile/link together. The older version of OpenGL with GLX does not seem to have the implementations of the shader extensions - and the newer OpenGL version (2.1) throws compile errors on the glX methods.
I have tried different combinatons of g++ compile and link commands to try to pull in the right libraries, but with no luck.
BTW, I am not using XCode or an IDE. The build is all command line.

Thanks, I will try the GLEW and see if it gives me a clue.
I ran otools a few times and I can see that wrong versions are being used and I have found where the correct libs exist, but I cannot get the compiler/linker to behave and pull (GLX) from one location and (2.1) from another location.