# Importing blocks to GRC **URL:** \ **Category:** GNU Radio\ **Created:** [May 28, 2014, 10:02pm UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061 "2014-05-28T22:02:54Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![jason\_sam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/7993a0/32.png) [@jason\_sam](https://www.ruby-forum.com/u/jason_sam)\ **Post date:** [May 28, 2014, 10:02pm UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/1 "2014-05-28T22:02:54Z")
Hi, I am working on a ubuntu machine and am following the HOWTO example as the following link shows. My program works fine until loading the howto\_square2\_ff module into the GRC library. The tutorial says that “If you do a make install from the build directory, you can use the block in GRC. If GRC is already running, you can hit the “Reload Blocks” button in the GRC toolbar; it’s a blue circular arrow on the right-hand side. You should now see a “HOWTO” category in the block tree.” After I executed the commands specified by the tutorial, I did not see any HOWTO blocks when I boot the GRC using $gnuradio-companion. Attached is a tarball of my code. Would be great to get comments. Thanks. [http://gnuradio.org/redmine/projects/gnuradio/wiki/OutOfTreeModules](http://gnuradio.org/redmine/projects/gnuradio/wiki/OutOfTreeModules) Pengyu ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 28, 2014, 10:27pm UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/2 "2014-05-28T22:27:31Z")
On Wed, May 28, 2014 at 1:01 PM, Pengyu Z. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > After I executed the commands specified by the tutorial, I did not see any > HOWTO blocks when I boot the GRC using $gnuradio-companion If all the tests pass then this usually means there is a problem with your xml files. You should remove and everything in it as those … aren’t allowed. Also sudo ldconfig ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 28, 2014, 10:44pm UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/3 "2014-05-28T22:44:31Z")
I executed $gr\_modtool makexml square2\_ff before. So the content in /gr-howto/grc/howto\_square2\_ff.xml should be correct. As you pointed that stuff should be removed, I also did $gr\_modtool makexml square\_ff. Now the content in /gr-howto/grc/howto\_square\_ff.xml is shown below. Although I did $make install and $sudo ldconfig, I still cannot see the block on GRC… Square ff howto\_square\_ff HOWTO import howto howto.square\_ff() in float out float ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 28, 2014, 10:57pm UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/4 "2014-05-28T22:57:59Z")
On Wed, May 28, 2014 at 1:43 PM, Pengyu Z. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I still cannot see the block on GRC I’m assuming you’re using ubuntu then. Check your python path echo $PYTHONPATH and ensure that you see the howto folder located there in the dist-packages ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 29, 2014, 3:38am UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/5 "2014-05-29T03:38:00Z")
On 05/28/2014 09:11 PM, Pengyu Z. wrote: > ``` > > wrote: > dist-packages > > ``` > > * * * > > Discuss-gnuradio mailing list > [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) > [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) > No, it’s an environment variable. A Linux shell thing. PYTHONPATH should be set to include the place where the installer installed the Python modules. Setting users environment variables is unrelated to building software. I usually set mine in my .bashrc: PYTHONPATH=.:$HOME/bin:/usr/local/lib/python2.7/site-packages:/usr/local/lib/python2.7/dist-packages PYTHONPATH=$PYTHONPATH:/usr/local/lib64/python2.7/site-packages:/usr/local/lib64/python2.7/dist-packages export PYTHONPATH ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 29, 2014, 3:12am UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/6 "2014-05-29T03:12:49Z")
When I do “echo $PYTHONPATH”, nothing shows up. How is $PYTHONPATH set? I thought it should be configured automatically by cmake and make. Correct? ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 29, 2014, 4:12am UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/7 "2014-05-29T04:12:34Z")
On Wed, May 28, 2014 at 6:36 PM, Marcus D. Leech [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Setting users environment variables is unrelated to building software. That’s right. I more wanted to make sure that the thing installed correctly. Pengyu, I downloaded your zip and rebuilt it on my machine with no errors. I can use your square2 ff block just fine in GRC which leads me to believe there is something off with your setup. Not sure of the right question to ask at the moment though… For fun, can you pastebin the output of cmake .. make make install ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 29, 2014, 6:30pm UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/8 "2014-05-29T18:30:14Z")
On Thu, May 29, 2014 at 5:13 AM, Pengyu Z. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I also think some configurations on my machine are not correct Let’s simplify the problem even more. It should be the case that when you place a xml file in /usr/local/share/gnuradio/blocks/ it will show up in GNU Radio Companion regardless of if you actually made the block. Do a sudo cp on howto\_square2\_ff.xml. Then open up GNU Radio and see if you can find the HOWTO category and the square block. If that doesn’t work, GNU Radio is likely searching somewhere else for new blocks similar to this problem [http://gnuradio.4.n7.nabble.com/Cannot-see-my-custom-blocks-in-GRC-td45780.htmlsince](http://gnuradio.4.n7.nabble.com/Cannot-see-my-custom-blocks-in-GRC-td45780.htmlsince) your versions match. I recommend updating. ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 29, 2014, 2:15pm UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/9 "2014-05-29T14:15:21Z")
Yeah. I also think some configurations on my machine are not correct. Here are the output of several commands. $ cmake … – The CXX compiler identification is GNU 4.8.2 – The C compiler identification is GNU 4.8.2 – Check for working CXX compiler: /usr/bin/c++ – Check for working CXX compiler: /usr/bin/c++ – works – Detecting CXX compiler ABI info – Detecting CXX compiler ABI info - done – Check for working C compiler: /usr/bin/cc – Check for working C compiler: /usr/bin/cc – works – Detecting C compiler ABI info – Detecting C compiler ABI info - done – Build type not specified: defaulting to release. – Boost version: 1.54.0 – Found the following Boost libraries: – filesystem – system – Found PkgConfig: /usr/bin/pkg-config (found version “0.26”) – checking for module ‘gnuradio-runtime’ – found gnuradio-runtime, version 3.7.2.1 – Found GNURADIO\_RUNTIME: /usr/lib/x86\_64-linux-gnu/libgnuradio-runtime.so – checking for module ‘cppunit’ – found cppunit, version 1.13.1 – Found CPPUNIT: /usr/lib/x86\_64-linux-gnu/libcppunit.so;dl – Found SWIG: /usr/bin/swig2.0 (found version “2.0.11”) – Found PythonLibs: /usr/lib/x86\_64-linux-gnu/libpython2.7.so (found suitable version “2.7.6”, minimum required is “2”) CMake Warning (dev) at cmake/Modules/GrSwig.cmake:25 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:44 ``` Argument not separated from preceding token by whitespace. Call Stack (most recent call first): swig/CMakeLists.txt:28 (include) This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at cmake/Modules/GrSwig.cmake:25 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:92 ``` Argument not separated from preceding token by whitespace. Call Stack (most recent call first): swig/CMakeLists.txt:28 (include) This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at cmake/Modules/GrSwig.cmake:25 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:100 ``` Argument not separated from preceding token by whitespace. Call Stack (most recent call first): swig/CMakeLists.txt:28 (include) This warning is for project developers. Use -Wno-dev to suppress it. – Found PythonInterp: /usr/bin/python2 (found suitable version “2.7.6”, minimum required is “2”) CMake Warning (dev) at swig/CMakeLists.txt:29 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:44 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at swig/CMakeLists.txt:29 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:92 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at swig/CMakeLists.txt:29 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:100 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. – Found Doxygen: /usr/bin/doxygen (found version “1.8.6”) CMake Warning (dev) at cmake/Modules/GrSwig.cmake:182 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:44 ``` Argument not separated from preceding token by whitespace. Call Stack (most recent call first): swig/CMakeLists.txt:47 (GR\_SWIG\_INSTALL) This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at cmake/Modules/GrSwig.cmake:182 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:92 ``` Argument not separated from preceding token by whitespace. Call Stack (most recent call first): swig/CMakeLists.txt:47 (GR\_SWIG\_INSTALL) This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at cmake/Modules/GrSwig.cmake:182 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:100 ``` Argument not separated from preceding token by whitespace. Call Stack (most recent call first): swig/CMakeLists.txt:47 (GR\_SWIG\_INSTALL) This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at python/CMakeLists.txt:23 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:44 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at python/CMakeLists.txt:23 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:92 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at python/CMakeLists.txt:23 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:100 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at apps/CMakeLists.txt:20 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:44 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at apps/CMakeLists.txt:20 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:92 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. CMake Warning (dev) at apps/CMakeLists.txt:20 (include): Syntax Warning in cmake code at ``` /home/vijaykp/gr-howto/cmake/Modules/GrPython.cmake:196:100 ``` Argument not separated from preceding token by whitespace. This warning is for project developers. Use -Wno-dev to suppress it. – Configuring done – Generating done – Build files have been written to: /home/vijaykp/gr-howto/build $ make Scanning dependencies of target gnuradio-howto [5%] Building CXX object lib/CMakeFiles/gnuradio-howto.dir/square\_ff\_impl.cc.o [10%] Building CXX object lib/CMakeFiles/gnuradio-howto.dir/square2\_ff\_impl.cc.o Linking CXX shared library libgnuradio-howto.so [10%] Built target gnuradio-howto Scanning dependencies of target test-howto [15%] Building CXX object lib/CMakeFiles/test-howto.dir/test\_howto.cc.o [21%] Building CXX object lib/CMakeFiles/test-howto.dir/qa\_howto.cc.o Linking CXX executable test-howto [21%] Built target test-howto Scanning dependencies of target \_howto\_swig\_doc\_tag [26%] Building CXX object swig/CMakeFiles/\_howto\_swig\_doc\_tag.dir/\_howto\_swig\_doc\_tag.cpp.o Linking CXX executable \_howto\_swig\_doc\_tag [26%] Built target \_howto\_swig\_doc\_tag Scanning dependencies of target \_howto\_swig\_swig\_tag [31%] Building CXX object swig/CMakeFiles/\_howto\_swig\_swig\_tag.dir/\_howto\_swig\_swig\_tag.cpp.o Linking CXX executable \_howto\_swig\_swig\_tag [31%] Built target \_howto\_swig\_swig\_tag [36%] Generating doxygen xml for howto\_swig\_doc docs Warning: Tag `SYMBOL_CACHE_SIZE' at line 289 of file /home/vijaykp/gr-howto/build/swig/howto_swig_doc_swig_docs/Doxyfile has become obsolete. To avoid this warning please remove this line from your configuration file or upgrade it using "doxygen -u" Warning: Tag `SHOW\_DIRECTORIES’ at line 477 of file /home/vijaykp/gr-howto/build/swig/howto\_swig\_doc\_swig\_docs/Doxyfile has become obsolete. To avoid this warning please remove this line from your configuration file or upgrade it using “doxygen -u” Warning: Tag `HTML_ALIGN_MEMBERS' at line 803 of file /home/vijaykp/gr-howto/build/swig/howto_swig_doc_swig_docs/Doxyfile has become obsolete. To avoid this warning please remove this line from your configuration file or upgrade it using "doxygen -u" Warning: Tag `USE\_INLINE\_TREES’ at line 956 of file /home/vijaykp/gr-howto/build/swig/howto\_swig\_doc\_swig\_docs/Doxyfile has become obsolete. To avoid this warning please remove this line from your configuration file or upgrade it using “doxygen -u” Warning: doxygen no longer ships with the FreeSans font. You may want to clear or change DOT\_FONTNAME. Otherwise you run the risk that the wrong font is being used for dot generated graphs. [42%] Generating howto\_swig\_doc.i [47%] Generating howto\_swig.tag [52%] Swig source Scanning dependencies of target \_howto\_swig [57%] Building CXX object swig/CMakeFiles/\_howto\_swig.dir/howto\_swigPYTHON\_wrap.cxx.o Linking CXX shared module \_howto\_swig.so [57%] Built target \_howto\_swig Scanning dependencies of target pygen\_swig\_34533 [63%] Generating howto\_swig.pyc [68%] Generating howto\_swig.pyo [89%] Built target pygen\_swig\_34533 Scanning dependencies of target pygen\_python\_62df5 [94%] Generating **init**.pyc [100%] Generating **init**.pyo [100%] Built target pygen\_python\_62df5 Scanning dependencies of target pygen\_apps\_9a6dd [100%] Built target pygen\_apps\_9a6dd $ make test Running tests… Test project /home/vijaykp/gr-howto/build Start 1: test\_howto 1/2 Test #1: test\_howto … Passed 0.00 sec Start 2: qa\_square\_ff 2/2 Test #2: qa\_square\_ff … Passed 0.36 sec 100% tests passed, 0 tests failed out of 2 Total Test time (real) = 0.37 sec $ sudo make install [10%] Built target gnuradio-howto [21%] Built target test-howto [26%] Built target \_howto\_swig\_doc\_tag [31%] Built target \_howto\_swig\_swig\_tag [57%] Built target \_howto\_swig [89%] Built target pygen\_swig\_34533 [100%] Built target pygen\_python\_62df5 [100%] Built target pygen\_apps\_9a6dd Install the project… – Install configuration: “Release” – Up-to-date: /usr/local/lib/cmake/howto/howtoConfig.cmake – Up-to-date: /usr/local/include/howto/api.h – Up-to-date: /usr/local/include/howto/square\_ff.h – Up-to-date: /usr/local/include/howto/square2\_ff.h – Installing: /usr/local/lib/libgnuradio-howto.so – Installing: /usr/local/lib/python2.7/dist-packages/howto/\_howto\_swig.so – Removed runtime path from “/usr/local/lib/python2.7/dist-packages/howto/\_howto\_swig.so” – Installing: /usr/local/lib/python2.7/dist-packages/howto/howto\_swig.py – Installing: /usr/local/lib/python2.7/dist-packages/howto/howto\_swig.pyc – Installing: /usr/local/lib/python2.7/dist-packages/howto/howto\_swig.pyo – Up-to-date: /usr/local/include/howto/howto/swig/howto\_swig.i – Installing: /usr/local/include/howto/howto/swig/howto\_swig\_doc.i – Up-to-date: /usr/local/lib/python2.7/dist-packages/howto/ **init**.py – Installing: /usr/local/lib/python2.7/dist-packages/howto/ **init**.pyc – Installing: /usr/local/lib/python2.7/dist-packages/howto/ **init**.pyo – Up-to-date: /usr/local/share/gnuradio/grc/blocks/howto\_square\_ff.xml – Up-to-date: /usr/local/share/gnuradio/grc/blocks/howto\_square2\_ff.xml $ sudo ldconfig $ On Wed, May 28, 2014 at 10:11 PM, Alfredo M. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![Pengyu\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/e79b87/32.png) [@Pengyu\_Z](https://www.ruby-forum.com/u/Pengyu_Z)\ **Post date:** [May 29, 2014, 8:23pm UTC](https://www.ruby-forum.com/t/importing-blocks-to-grc/230061/10 "2014-05-29T20:23:18Z")
I think the default GNU Radio search path is /usr/share/gnuradio/grc/blocks because all existing blocks are stored within this directory. I added the new path into GRC\_BLOCKS\_PATH variable. export GRC\_BLOCKS\_PATH=/usr/local/share/gnuradio/grc/blocks:$GRC\_BLOCKS\_PATH Now I can see the howto block in GRC. For a quick test, I connected a constant source 0.5 to the howto module. The output of howto module is 0.25, which is the square of input. Therefore, the gr-howto block functions as expected. However, when I run the GRC, I saw one error message and am not sure what it indicates. libGL error: failed to load driver: swrast On Thu, May 29, 2014 at 12:28 PM, Alfredo M. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)