OK I did some more trouble shooting to narrow down the problem. I
decided to start with C++ code from a block that I knew already
worked.
I extracted the file gr-howto-write-a-block-3.0.4.tar.gz. I then
installed the block using the normal configure, make, and make
install procedure. I then created a python program called
squaredaudio.py to test the howto_square2_ff block. It worked
correctly. I’ve attached this file.
Then I created new c++ source files in the topdir/src/lib/
directory. They were howto_square3_ff.cc and howto_square3_ff.h.
The goal here was to create a copy of the howto_square2_ff block
only under another name. I copied the source files for the square
2 block into the source files for the square 3 block. I changed
the names from square2 to square3. I modified the howto.i with
the additional lines of codes for the new block. I based these off
of what was already in the file for square_ff and square2_ff.
Next I modifed the file topdir/src/lib/makefile.am. I added the
file names howto_square3_ff.cc and howto_square3_ff.h next to the
places where the file names for the other blocks were.
All other files were left as they came in the tar.gz file. When
the block is installed I don’t get an error. However when I run my
test program I get an error which I’ve included in error.txt.
The main part seems to be:
/usr/local/lib/python2.5/site-packages/gnuradio/_howto.so: undefined
symbol: _Z21howto_make_square3_ffv
This error is the same whether I try to use the howto_square2_ff or
howto_square3_ff block in squaredaudio.py.
I get the feeling I’m supposed to modify some other files but I can’t
figure out what to change. Any ideas?
Thanks,
Keith