6.14 Using Python

The Ports Collection supports parallel installation of multiple Python versions. Ports should make sure to use a correct python interpreter, according to the user-settable PYTHON_VERSION variable. Most prominently, this means replacing the path to python executable in scripts with the value of PYTHON_CMD variable.

Ports that install files under PYTHON_SITELIBDIR should use the pyXY- package name prefix, so their package name embeds the version of Python they are installed into.


Table 6-21. Most Useful Variables for Ports That Use Python

USE_PYTHON The port needs Python. Minimal required version can be specified with values such as 2.6+. Version ranges can also be specified, by separating two version numbers with a dash, e.g.: 2.6-2.7
USE_PYDISTUTILS Use Python distutils for configuring, compiling and installing. This is required when the port comes with setup.py. This overrides the do-build and do-install targets and may also override do-configure if GNU_CONFIGURE is not defined.
PYTHON_PKGNAMEPREFIX Used as a PKGNAMEPREFIX to distinguish packages for different Python versions. Example: py24-
PYTHON_SITELIBDIR Location of the site-packages tree, that contains installation path of Python (usually LOCALBASE). The PYTHON_SITELIBDIR variable can be very useful when installing Python modules.
PYTHONPREFIX_SITELIBDIR The PREFIX-clean variant of PYTHON_SITELIBDIR. Always use %%PYTHON_SITELIBDIR%% in pkg-plist when possible. The default value of %%PYTHON_SITELIBDIR%% is lib/python%%PYTHON_VERSION%%/site-packages
PYTHON_CMD Python interpreter command line, including version number.
PYNUMERIC Dependency line for numeric extension.
PYNUMPY Dependency line for the new numeric extension, numpy. (PYNUMERIC is deprecated by upstream vendor).
PYXML Dependency line for XML extension (not needed for Python 2.0 and higher as it is also in base distribution).
USE_TWISTED Add dependency on twistedCore. The list of required components can be specified as a value of this variable. Example: web lore pair flow
USE_ZOPE Add dependency on Zope, a web application platform. Change Python dependency to Python 2.7. Set ZOPEBASEDIR containing a directory with Zope installation.

A complete list of available variables can be found in /usr/ports/Mk/bsd.python.mk.

For questions about the FreeBSD ports system, e-mail <ports@FreeBSD.org>.
For questions about this documentation, e-mail <doc@FreeBSD.org>.