On Tue, 15 Feb 2011, Roman Chyla wrote:
from: http://realmike.org/blog/2010/07/18/python-extensions-in-cpp-using-swig/
Q. ?Fatal Python error: Interpreter not initialized (version mismatch?)?
A. This error occurs when the version of the Python interpreter for
which the extension module has been built is different from the
version of the interpreter that attempts to import the module.
Is there a way to find out which python interpreter version is inside
JCC? Also, Is it somehow possible that the java process that load jcc
library will be picking the default python (2.4) instead of the python
(2.5)? PATH is set to python2.5.
There is no Python interpreter inside jcc. It's dynamically linked.
To know which version of the shared library is looked for and expected, use
the 'ldd' utility against the various shared libraries involved to tell you.
That version is selected at build time, when you run 'python setup.py ...'
That version of python determines the version of libpython.so used.
Andi..
Cheers,
roman
On Tue, Feb 15, 2011 at 2:40 AM, Roman Chyla <roman.ch...@gmail.com> wrote:
On Tue, Feb 15, 2011 at 1:32 AM, Andi Vajda <va...@apache.org> wrote:
On Tue, 15 Feb 2011, Roman Chyla wrote:
The python embedded in Java works really well on MacOsX and also
Ubuntu. But I am trying hard to make it work also on Scientific Linux
(SLC5) with *statically* built Python. The python is a build from
ActiveState.
You mean you're going to try to dynamically load libpython.a into a JVM ?
I have no idea if this can work at all.
I am very ignorant as far as the difference between statically and
dynamically linked libraries go - I just wanted to use JCC wrapped
code with this particular statically linked python
I got little bit further, but just little:
after I changed -Xlinker --export-dynamic into "-Xlinker
-export-dynamic" (and installed python into /opt...) I am getting a
different error:
SEVERE: org.apache.jcc.PythonException: No module named solrpie.java_bridge
null
at org.apache.jcc.PythonVM.instantiate(Native Method)
at rca.python.jni.PythonVMBridge.start(Unknown Source)
at rca.python.jni.PythonVMBridge.start(Unknown Source)
at rca.python.jni.PythonVMBridge.start(Unknown Source)
at rca.python.jni.SolrpieVM.getBridge(Unknown Source)
My understanding is that the previous error has gone (and the python
module "time" is loaded), because if I set PYTHONPATH incorrectly, I
get:
This message is IMHO coming from Python
But when I correct the PYTHONPATH, I am getting only this:
[java] Fatal Python error: Interpreter not initialized (version mismatch?)
[java] Java Result: 134
If my understanding of static builds is correct, I'd imagine the only way
for this to work would be to statically compile the JVM (hotspot) and python
together.
oooups, that is way over my head
But why all this ?
Because on the grid, we already had a statically linked python and it
was working very well with pylucene (and after all, I managed to make
it work also for solr and other packages)
But if you think that it is not possible, I should do something else :)
But it was fun trying, if you get some idea, please let me know.
Thank you,
Roman
Andi..
So far, I managed to build all the needed extensions (jcc, lucene,
solr) and I can run them in python, but when I try to start the java
app and use python, I get:
SEVERE: org.apache.jcc.PythonException:
/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/lib-dynload/time.so:
undefined symbol: PyExc_IOError
I understand, that the missing symbol PyExc_IOError is in the static
python library:
bash-3.2$ nm
/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/config/libpython2.5.a
| grep IOError
0000000000004120 D PyExc_IOError
0000000000004140 d _PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
So when building JCC, I build with these arguments:
lflags + ['-lpython%s.%s' %(sys.version_info[0:2]),
'-L',
'/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/config',
'-rdynamic',
'-Wl,--export-dynamic',
'-Xlinker',
'--export-dynamic']
I just found instructions at:
http://stackoverflow.com/questions/4223312/python-interpreter-embedded-in-the-application-fails-to-load-native-modules
I don't really understand g++, but the symbol is there after the
compilation
bash-3.2$ nm
/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/site-packages/JCC-2.7-py2.5-linux-x86_64.egg/libjcc.so
| grep IOError
0000000000352240 D PyExc_IOError
0000000000352260 d _PyExc_IOError
And when starting java, I do
"-Djava.library.path=/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/site-packages/JCC-2.7-py2.5-linux-x86_64.egg"
The code works find on mac (python 2.6) and ubuntu (python2.6), but
not this statically linked python2.5 - would you know what I can try?
Thanks.
roman
PS: I tried several compilations, but I was usually re-compiling JCC
without building lucene etc again, I hope that is not the problem.
