You should be able to read the output of that command with [1]. Make sure
that you use the --file option before your output file name. I tried the
command you ran and didn't get any output because I didn't have --file
before the output name. Maybe a version difference?
By default it seems that
I am trying to come up to speed on running gnu-radio python scripts outside of
GRC and have run into a problem.
From
https://wiki.gnuradio.org/index.php/Guided_Tutorial_GNU_Radio_in_Python#3.1.1._GRC_Generated_Python_Files
(specifically 3.1 Intro to Using GNU Radio with Python) where I copied
