Compiling Your Module

XOSD

Building Your Module Using gcc

To build your module using gcc is a three step process on Unix. Under Windows® it is easier to use distutils than to compile your module using a compiler.

1. Start by running the Pyrex compiler over your code as follows, where mymodule.pyx is the name of the Pyrex module you are writing.

   bash$ python2.2 pyrexc mymodule.pyx

2. Next, compile the resulting C file into a .o file. The call to gcc looks like this:

   bash$ gcc -c -fPIC -I/usr/include/python2.2/ mymodule.c

   The arguments to gcc are explained below.

   -c

   Produces a .o file instead of an executable.

   -fPIC

   Produces position independent code, so we can dynamically link against it later.

   -I/usr/include/python2.2/

   is the location of the Python 2.2 include file. The location of your Python include file may differ from /usr/include/python2.2/.

   mymodule.c

   is the name of the C file produced by Pyrex.

3. Finally, link the .o into a .so:

   bash$ gcc -shared mymodule.o -lxosd -o mymodule.so

   -shared

   produces a shared-object file, instead of an executable.

   mymodule.o

   is the name of the module you wish to compile.

   -lxosd

   links against the C-library xosd.

   -o mymodule.so

   causes gcc to put the output into a file called mymodule.so

   In the general case, the C library that you are wrapping will probably differ from xosd. In some cases, such as compiling the primes.pyx demo that is shipped with Pyrex, you will not need to supply any library name as an argument.

After creating the .so module you then import it into Python.

Building Your Module Using distutils

Instead of using the command-line (or make) to compile your modules, you may find it easier (especially on Windows®) to use distutils.

The following is a distutils setup file that compiles a Pyrex module called mymodule.

from distutils.core import setup
from distutils.extension import Extension
from Pyrex.Distutils import build_ext
setup(
  name = "PyrexGuide",
  ext_modules=[ 
    Extension("mymodule", ["mymodule.pyx"], libraries = ["xosd"])
    ],
  cmdclass = {'build_ext': build_ext}
)

Multiple modules can be added to the setup file by adding more instances of Extension classes to the ext_modules list. Save the above code in a file called setup.py and run the following code to build your module.

bash$ python2.2 setup.py build_ext --inplace

Using Your Module

After building your module, you can import the module into Python 2.2 using the import statement.

import mymodule
print dir(mymodule)