Creating C++ OOT with gr-modtool

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TODO: intro material

The previous tutorial, Creating Python OOT with gr-modtool, describes how to create a Python block in an OOT module. This c++ OOT tutorial builds upon the previous Python one, so it is is suggested to at least complete the Creating an OOT Module portion of that tutorial before completing this one.

TODO: pick up from python OOT tutorial

TODO: link back to python tutorial

Installation Note

This tutorial was written using GNU Radio v3.10.1.1 on Ubuntu 21.10, installed using the Ubuntu PPA from the Installation Wiki Page. The basic GNU Radio install using:

$ sudo apt-get install gnuradio

does not come with the proper libraries needed to compile and install OOT modules. Consider installing the following packages before continuing:

$ sudo apt-get install gnuradio-dev cmake libspdlog-dev clang-format

Adding a New Block

Move to the gr-customModule directory created in the Creating Python OOT with gr-modtool tutorial:

cd your-path/gr-customModule

Add a new block named multDivSelector:

$ gr_modtool add multDivSelector

The types of blocks will be displayed:

GNU Radio module name identified: customModule
('sink', 'source', 'sync', 'decimator', 'interpolator', 'general', 'tagged_stream', 'hier', 'noblock')

Enter sync as the block type:

Enter block type: sync

Enter cpp as the language:

Language (python/cpp): cpp
Language: C++
Block/code identifier: multDivSelector

Enter the name or organization of the copyright holder:

Please specify the copyright holder: YourName

Create a boolean variable selector with a default value of true:

Enter valid argument list, including default arguments: 
bool selector=true

Select whether or not QA code is desired:

Add Python QA code? [Y/n] n
Add C++ QA code? [Y/n] n

Multiple files will then be created or modified:

Adding file 'lib/multDivSelector_impl.h'...
Adding file 'lib/multDivSelector_impl.cc'...
Adding file 'include/gnuradio/customModule/multDivSelector.h'...
Adding file 'python/customModule/bindings/docstrings/multDivSelector_pydoc_template.h'...
Adding file 'python/customModule/bindings/multDivSelector_python.cc'...
Adding file 'grc/customModule_multDivSelector.block.yml'...
Editing grc/CMakeLists.txt...