How would you design a real time application for cnc control in c / c++ ???

user@linuxcnc:~$ git clone git://github.com/pybind/pybind11 pybind
Cloning into 'pybind'...
remote: Enumerating objects: 36, done.
remote: Counting objects: 100% (36/36), done.
remote: Compressing objects: 100% (32/32), done.
remote: Total 13933 (delta 10), reused 12 (delta 1), pack-reused 13897
Receiving objects: 100% (13933/13933), 5.45 MiB | 4.68 MiB/s, done.
Resolving deltas: 100% (9471/9471), done.
user@linuxcnc:~$ git submodule update --init
fatal: not a git repository (or any of the parent directories): .git
user@linuxcnc:~$ cd pybind/
user@linuxcnc:~/pybind$ git submodule update --init
user@linuxcnc:~/pybind$ mkdir build
user@linuxcnc:~/pybind$ cd build
user@linuxcnc:~/pybind/build$ cmake
Usage

  cmake [options] <path-to-source>
  cmake [options] <path-to-existing-build>
  cmake [options] -S <path-to-source> -B <path-to-build>

Specify a source directory to (re-)generate a build system for it in the
current working directory.  Specify an existing build directory to
re-generate its build system.

Run 'cmake --help' for more information.

user@linuxcnc:~/pybind/build$ cmake ..
-- The CXX compiler identification is GNU 8.3.0
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- pybind11 v2.6.2 dev1
-- CMake 3.13.4
-- Found PythonInterp: /usr/bin/python3.7 (found version "3.7.3") 
-- Found PythonLibs: python3.7m
-- PYTHON 3.7.3
-- Performing Test HAS_FLTO
-- Performing Test HAS_FLTO - Success
-- pybind11::lto enabled
-- pybind11::thin_lto enabled
-- Setting tests build type to MinSizeRel as none was specified
-- Building tests with Eigen v3.3.7
-- Could NOT find Boost
CMake Warning at tools/pybind11Common.cmake:248 (message):
  Missing: pytest 3.1

  Try: /usr/bin/python3.7 -m pip install pytest
Call Stack (most recent call first):
  tests/CMakeLists.txt:357 (pybind11_find_import)


-- Catch not detected. Interpreter tests will be skipped. Install Catch headers manually or use `cmake -DDOWNLOAD_CATCH=ON` to fetch them automatically.
-- Configuring done
-- Generating done
-- Build files have been written to: /home/user/pybind/build
user@linuxcnc:~/pybind/build$ make
Scanning dependencies of target pybind11_cross_module_tests
[  2%] Building CXX object tests/CMakeFiles/pybind11_cross_module_tests.dir/pybind11_cross_module_tests.cpp.o
In file included from /home/user/pybind/include/pybind11/pytypes.h:12,
                 from /home/user/pybind/include/pybind11/cast.h:13,
                 from /home/user/pybind/include/pybind11/attr.h:13,
                 from /home/user/pybind/include/pybind11/pybind11.h:45,
                 from /home/user/pybind/tests/pybind11_tests.h:2,
                 from /home/user/pybind/tests/pybind11_cross_module_tests.cpp:10:
/home/user/pybind/include/pybind11/detail/common.h:124:10: fatal error: Python.h: No such file or directory
 #include <Python.h>
          ^~~~~~~~~~
compilation terminated.
make[2]: *** [tests/CMakeFiles/pybind11_cross_module_tests.dir/build.make:63: tests/CMakeFiles/pybind11_cross_module_tests.dir/pybind11_cross_module_tests.cpp.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:134: tests/CMakeFiles/pybind11_cross_module_tests.dir/all] Error 2
make: *** [Makefile:130: all] Error 2
user@linuxcnc:~/pybind/build$ 

[1009010] Installation finished!
[1041917] run application as detached process: "/home/user/Qt/Tools/QtCreator/bin/qtcreator" () "/home/user"

user@linuxcnc:~$ /home/user/Qt/Tools/QtCreator/bin/qtcreator
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.

Aborted
user@linuxcnc:~$ 

user@linuxcnc:~/Qt/Tools/QtCreator/bin$ ./qtcreator.sh 
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.

Aborted

/usr/include/c++/8/cstdlib:75: error: stdlib.h: No such file or directory
 #include_next <stdlib.h>
               ^~~~~~~~~~

qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.

Aborted

user@linuxcnc:~$ export QT_DEBUG_PLUGINS=1
user@linuxcnc:~$ export QT_DEBUG_PLUGINS
user@linuxcnc:~$ bash ./Qt/Tools/QtCreator/bin/qtcreator.sh 
QFactoryLoader::QFactoryLoader() checking directory path "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms" ...
QFactoryLoader::QFactoryLoader() looking at "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqeglfs.so"
Found metadata in lib /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqeglfs.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "eglfs"
        ]
    },
    "archreq": 0,
    "className": "QEglFSIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("eglfs")
QFactoryLoader::QFactoryLoader() looking at "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqlinuxfb.so"
Found metadata in lib /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqlinuxfb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "linuxfb"
        ]
    },
    "archreq": 0,
    "className": "QLinuxFbIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("linuxfb")
QFactoryLoader::QFactoryLoader() looking at "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqminimal.so"
Found metadata in lib /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqminimal.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimal"
        ]
    },
    "archreq": 0,
    "className": "QMinimalIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("minimal")
QFactoryLoader::QFactoryLoader() looking at "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqminimalegl.so"
Found metadata in lib /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqminimalegl.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimalegl"
        ]
    },
    "archreq": 0,
    "className": "QMinimalEglIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("minimalegl")
QFactoryLoader::QFactoryLoader() looking at "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqoffscreen.so"
Found metadata in lib /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqoffscreen.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "offscreen"
        ]
    },
    "archreq": 0,
    "className": "QOffscreenIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("offscreen")
QFactoryLoader::QFactoryLoader() looking at "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqvnc.so"
Found metadata in lib /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqvnc.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "vnc"
        ]
    },
    "archreq": 0,
    "className": "QVncIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("vnc")
QFactoryLoader::QFactoryLoader() looking at "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqxcb.so"
Found metadata in lib /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqxcb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "xcb"
        ]
    },
    "archreq": 0,
    "className": "QXcbIntegrationPlugin",
    "debug": false,
    "version": 331520
}


Got keys from plugin meta data ("xcb")
QFactoryLoader::QFactoryLoader() checking directory path "/home/user/Qt/Tools/QtCreator/bin/platforms" ...
Cannot load library /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqxcb.so: (libxcb-util.so.1: cannot open shared object file: No such file or directory)
QLibraryPrivate::loadPlugin failed on "/home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqxcb.so" : "Cannot load library /home/user/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqxcb.so: (libxcb-util.so.1: cannot open shared object file: No such file or directory)"
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.

Aborted