name : apiabiversion.rst.txt .. highlightlang:: c .. _apiabiversion: *********************** API and ABI Versioning *********************** ``PY_VERSION_HEX`` is the Python version number encoded in a single integer. For example if the ``PY_VERSION_HEX`` is set to ``0x030401a2``, the underlying version information can be found by treating it as a 32 bit number in the following manner: +-------+-------------------------+------------------------------------------------+ | Bytes | Bits (big endian order) | Meaning | +=======+=========================+================================================+ | ``1`` | ``1-8`` | ``PY_MAJOR_VERSION`` (the ``3`` in | | | | ``3.4.1a2``) | +-------+-------------------------+------------------------------------------------+ | ``2`` | ``9-16`` | ``PY_MINOR_VERSION`` (the ``4`` in | | | | ``3.4.1a2``) | +-------+-------------------------+------------------------------------------------+ | ``3`` | ``17-24`` | ``PY_MICRO_VERSION`` (the ``1`` in | | | | ``3.4.1a2``) | +-------+-------------------------+------------------------------------------------+ | ``4`` | ``25-28`` | ``PY_RELEASE_LEVEL`` (``0xA`` for alpha, | | | | ``0xB`` for beta, ``0xC`` for release | | | | candidate and ``0xF`` for final), in this | | | | case it is alpha. | +-------+-------------------------+------------------------------------------------+ | | ``29-32`` | ``PY_RELEASE_SERIAL`` (the ``2`` in | | | | ``3.4.1a2``, zero for final releases) | +-------+-------------------------+------------------------------------------------+ Thus ``3.4.1a2`` is hexversion ``0x030401a2``. All the given macros are defined in :source:`Include/patchlevel.h`.