Gnu radio companion (grc) is a graphical tool for creating signal flow graphs and generating flow-graph source code.
gnuradio-companion: [options] [saved flow graphs]
-h, --help
show this help message and exit.
-v, --version
show program's version number and exit
-c, --compile
Only compile the GRC file without invoking the GUI. Useful for unit testing, running gnuradio-companion from a Makefile and other command-line scripting.
-d, --output-dir
Output path for the Python file.
Invoke the program with an XML file saved by a previous run.
The full documentation for gnuradio-companion is maintained as an HTML file. See http://gnuradio.org/redmine/projects/gnuradio/wiki/GNURadioCompanion