Different behaviour: python vs. ipython when using a C module

I may be having a much simpler problem, simply trying to import sys in the C module and having problem with IPython:

void module_start() {
        sprintf(buf, "sys.path.append('%s/lib/python')", get_module_home());
        assert(PyRun_SimpleString("import sys") == 0);
}

Which runs fine in python but not in IPython with the following error:

---------------------------------------------------------------------------
exceptions.NameError                                 Traceback (most recent call last)

/path/path/to/current/directory/<string>

NameError: name 'sys' is not defined

Any insights?

In the pasted code the assert simply fails when load module in IPython but not in Python. If the assert were removed, I got the error response as in the 2nd box.

Replying to yichun:

I may be having a much simpler problem, simply trying to import sys in the C module and having problem with IPython: {{{ #!c void module_start() { sprintf(buf, "sys.path.append('%s/lib/python')", get_module_home()); assert(PyRun?_SimpleString("import sys") == 0); } }}} Which runs fine in python but not in IPython with the following error: {{{ --------------------------------------------------------------------------- exceptions.NameError? Traceback (most recent call last) /path/path/to/current/directory/<string> NameError?: name 'sys' is not defined }}} Any insights?

Sorry without the assert, the error message is:

---------------------------------------------------------------------------
exceptions.ImportError                               Traceback (most recent call last)

/path/to/src/<string> 

ImportError: __import__ not found
---------------------------------------------------------------------------
exceptions.NameError                                 Traceback (most recent call last)

/path/to/src/<string> 

NameError: name 'sys' is not defined

I'm afraid I don't really know what the problem is here, but the ticket will stay open until we figure out what's going on.

It would help enormously if you could attach a self-contained complete example, including the necessary makefile, so that a potential reviewer can just grab the example and run it quickly. The more a possible reviewer has to do to even start this, the less your chances of getting someone else to help.

a .c file and a setup.py, modified from the famous fibo example code.

Sorry for the late reply. I just get a time to make an example, modified from the fibo example code. Only a "PyRun?_SimpleString("import sys");" was added.

It runs fine under Python. But having ImportError?: import not found messages when doing "import fibo".