[Discuss-gnuradio] where is usrp2_make_source_32fc actually defined?

[Tom Gross]

I've been trying to create a usrp2 dual source class for a number of
weeks now, and I've come to realize there is something fundamental
about this development environment that I don't understand.

Basically i've been installing gnuradio and grc on a variety of Ubuntu
machines buy building gnuradio-3.2.2 thus:

cd gnuradio-3.2.2
./configure --prefix=/usr
make
sudo make install

I've also been making custom blocks using gr-howto-write-a-block-3.2.2.

Lately I've tried to create usrp2_dsource_16sc and
usrp2_dual_source_32fc (slightly different naming conventions just to
see if it would make a difference) in gnuradio-3.2.2/gr-usrp2/src by
mimicing exactly how it is done for the existing single-channel
classes.

Everything builds, but at run-time I am getting an "ImportError"
symbol undefined for _Z23usrp2_make_dsource_16scRKSsS0_

I did an "nm -a _usrp.so | grep make" in
/usr/lib/python2.6/dist-packages/gnuradio and see this:

0000d1b3 T _Z12make_int_ptrv
0000d238 T _Z13make_long_ptrv
0000d12e T _Z15make_uint16_ptrv
         U _Z20usrp2_make_sink_16scRKSsS0_
         U _Z20usrp2_make_sink_32fcRKSsS0_
         U _Z22usrp2_make_source_16scRKSsS0_
         U _Z22usrp2_make_source_32fcRKSsS0_
         U _Z23usrp2_make_dsource_16scRKSsS0_
         U _Z27usrp2_make_dual_source_32fcRKSsS0_
0000d1d7 t _wrap_make_int_ptr
0000d25c t _wrap_make_long_ptr
0000d152 t _wrap_make_uint16_ptr

What I've noticed now is that even in the original _usrp2.so built
from the unmodified gnuradio-3.2.2 source, which works, the make
methods for sink and source appear to be undefined, according to "nm
-a".

So where are they defined?  I'm hoping that if I knew how these
methods are resolved at run-time in the "off-the-shelf" version of the
code, I would see why modified code is not working.

-Tom