Libtool error with howto example (_howto.la)

Hi,

Please bear with me as I am new to gnuradio (and autotools in
general). I am catching up … Gnuradio version 3.0.3 as such compiles
fine on my system (Cygwin on XP), and I am able to run all the
examples. But, I am having a problem getting the howto example to
work.

I have setup a new directory structure under the gnuradio (ver 3.0.3)
main directory, and copied the howto example files to that directory
(as per the article on creating a new block).

I added a new M4 file in config following the examples used for other
directories, ran “bootstrap”, “configure”, and then “make” in the
gnuradio subdirectory. When I do this, I am getting the following
error from libtool:

g++ -DHAVE_CONFIG_H -I. -I. -I…/…/…
-I…/…/…/gnuradio-core/src/lib/runtime
-I…/…/…/gnuradio-core/src/lib/general
-I…/…/…/gnuradio-core/src/lib/general
-I…/…/…/gnuradio-core/src/lib/filter
-I…/…/…/gnuradio-core/src/lib/filter
-I…/…/…/gnuradio-core/src/lib/reed-solomon
-I…/…/…/gnuradio-core/src/lib/io
-I…/…/…/gnuradio-core/src/lib/g72x
-I…/…/…/gnuradio-core/src/lib/omnithread
-I…/…/…/gnuradio-core/src/lib/swig
-I…/…/…/gnuradio-core/src/lib/swig -I/usr/local/include
-I/usr/include/boost-1_33_1 -I/usr/include/python2.5 -g -O2 -Wall
-Woverloaded-virtual -MT howto_square_ff.lo -MD -MP -MF
.deps/howto_square_ff.Tpo -c howto_square_ff.cc -DDLL_EXPORT -DPIC -o
.libs/howto_square_ff.o
/bin/sh …/…/…/libtool --tag=CXX --mode=link g++ -g -O2 -Wall
-Woverloaded-virtual -o _howto.la -rpath
/usr/local/lib/python2.5/site-packages/gnuradio --module
–avoid-version howto_square_ff.lo -lwinmm
libtool: link: libtool library _howto.la' must begin withlib’
Try libtool --help --mode=link' for more information. make[2]: *** [_howto.la] Error 1 make[2]: Leaving directory/usr/src/gnuradio-3.0.3/gr-vijay/src/lib’
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/usr/src/gnuradio-3.0.3/gr-vijay/src’
make: *** [all-recursive] Error 1

The problem is here:
libtool: link: libtool library _howto.la' must begin withlib’

Can someone please provide a clue as to what might be wrong ? I
greatly appreciate your time.

Thanks,
Vijay.

Vijay Ramasami wrote:

Please bear with me as I am new to gnuradio (and autotools in
general). I am catching up … Gnuradio version 3.0.3 as such compiles
fine on my system (Cygwin on XP), and I am able to run all the
examples. But, I am having a problem getting the howto example to
work.

I have setup a new directory structure under the gnuradio (ver 3.0.3)
main directory, and copied the howto example files to that directory
(as per the article on creating a new block).

So far, so good.

I added a new M4 file in config following the examples used for other
directories, ran “bootstrap”, “configure”, and then “make” in the
gnuradio subdirectory. When I do this, I am getting the following
error from libtool:

This is where your misunderstanding comes in.

There are two types of compilation from source for GNU Radio. The
successful build that you did of 3.0.3 is calling “building inside the
tree.”

The gr-howto-write-a-block example is meant for building “outside the
tree”, that is, independent of the main GNU Radio code. This is a
template for users to create their own signal processing blocks that
live independent from the main project code and only need access to the
(installed) header files.

The short answer is that you can untar the
gr-howto-write-a-block-3.0.3.tar.gz file into its own directory, then
run (from inside that directory):

$ ./configure
$ make
$ sudo make install

This will build and install the howto example onto your system. You can
use this as a template to start your own library of C++ based blocks
(search and replace on ‘howto’ to get started.)


Johnathan C.
Corgan Enterprises LLC
http://corganenterprises.com

Johnathan C. wrote:

I have setup a new directory structure under the gnuradio (ver 3.0.3)
main directory, and copied the howto example files to that directory
(as per the article on creating a new block).

So far, so good.

I wasn’t clear–you don’t need to have this directory be underneath the
main GNU Radio source tree; it can be anywhere. But wherever you put
the howto example, GNU Radio still must already be compiled and
installed on your machine.


Johnathan C.
Corgan Enterprises LLC
http://corganenterprises.com

Hi John,

Thank you very much for the help. I didn’t know that the howto example
was distributed as a tar.gz file. I created all the files from scratch
(by copy/pasting from the article). Anyway, I am clear about this now.

Regards,
Vijay.