SDR (Software Defined Radio)

Looks like GnuRadio 3.9.0 (i.e. master in gnuradio) switched from 'boost::shared_ptr' to 'std::shared_ptr' for the method 'gnuradio::get_initial_sptr()'.
I quickly replaced them (with: find . -type f | xargs grep -l 'boost::shared_ptr' | while read file; do sed -i 's/boost::shared_ptr/std::shared_ptr/' $file; done), and after this change I was able to compile gr-osmosdr without any problem.
I thought you might find this useful when you start the 3.9 branch.

Franco