spin -f "!(`cat urcu_progress.ltl | grep -v ^//`)" >> pan.ltl
urcu_progress_writer_error: clean urcu_progress_writer_error_ltl \
spin -f "!(`cat urcu_progress.ltl | grep -v ^//`)" >> pan.ltl
urcu_progress_writer_error: clean urcu_progress_writer_error_ltl \