ctypes 0.9.1 released

[Thomas Heller]

ctypes 0.9.1 released - Sept 14, 2004
=====================================

Overview

    ctypes is a ffi (Foreign Function Interface) package for Python
    2.3 and higher.

    ctypes allows to call functions exposed from dlls/shared libraries
    and has extensive facilities to create, access and manipulate
    simple and complicated C data types in Python - in other words:
    wrap libraries in pure Python.  It is even possible to implement C
    callback functions in pure Python.

    ctypes runs on Windows, MacOS X, Linux, Solaris, FreeBSD.  It may
    also run on other systems, provided that libffi supports this
    platform.

    On windows, ctypes contains a ctypes.com package which allows to
    call and implement custom COM interfaces.


Changes in 0.9.1

  ctypes 0.9.1 should be fully compatible again with Gary Bishop's
  readline module which is also used by IPython.

  ctypes changes

    The internal conversions that ctypes does between unicode and
    strings can now use a specified encoding and error handling.  A
    set_conversion_mode() function allows to set them, it returns the
    previous values.  The inital values are ('mbcs', 'ignore') on
    Windows, and ('ascii', 'strict') on other systems.

    When internal processing of an argument for a function call fails,
    the new ctypes.ArgumentError is raised.

    CDLL and its subclasses now accept an optional second handle
    parameter.  If this is supplied, it is used instead of calling
    LoadLibrary() or dlopen() to get one.

    Sometimes objects have been freed too early when calling functions
    where argtypes have been set.

    Fixed the create_unicode_buffer function - it was returning c_char
    arrays instead of c_wchar arrays.

    Both create_string_buffer and create_unicode_buffer can now be
    called with string and unicode instances, they will do the needed
    conversions themselves.

    ctypes now allows calling Python C api functions.  The 'pythonapi'
    symbol should be used to access these functions, this will
    automatically use the correct calling convention and exception
    handling.  The 'py_object' type is the ctypes variant of 'PyObject *'.
    This feature should also work if you are using a static python
    build.

    It is now possible to call cdecl functions with more arguments
    than the length of the argtypes sequence specifies - this allows
    to provide functions like sprintf() with a proper prototype.

    It is now possible to create strings or unicode strings if you
    have the integer address by calling c_char_p(address) or
    c_wchar_p(address).  Integers can also be assigned to structure
    fields of type c_char_p and c_wchar_p.

    c_char_p and c_wchar_p both accept strings and unicode strings -
    if needed they are encoded or decoded using 'strict' error
    handling.

    The _ctypes.call_function function, although private and
    deprecated, has been put back in - it is used by Gary Bishop's
    readline module.

    Array and pointer instances now support slicing, for pointers only
    getslice is implemented (setslice is too dangerous, probably).
    Slices are represented as lists of the elements, except
    for character and unicode character pointer and arrays, where
    strings resp. unicode strings are used instead.

    On windows, the include files were missing from the source
    distribution.

    The alignment function was not exported by the ctypes module.  It
    returns the alignment requirements in bytes of a type or instance.


  ctypes.com changes

    Applied a patch from Bruce Dodson which fixes an infinite loop in
    readtlb.py if a typelib references types defined in another
    typelib.  readtlb still generates bad code for such cases, but the
    results could be edited by hand if the dependencies can be sorted
    out.

    ctypes now caches the types that WINFUNCTYPE and CFUNCTYPE
    creates, to avoid unneeeded creation of classes. This
    makes importing files containing a lot of COM interfaces (like the
    ones that the readtlb tool generates) a lot (10 x) faster.

    COM servers now print a short usage message when they are run
    without the /regserver or /unregserver flag.

    VARIANT does now handle the COM DATE type (VT_DATE) as Python
    datetime.

    VARIANT now handles integers and longs correctly - if longs are
    too large they are stored as doubles (VT_R8). Integers are now
    stored as VT_I4 instead of VT_INT.

    Detailed changelogs are in CVS:
    
  <http://cvs.sourceforge.net/viewcvs.py/ctypes/ctypes/ChangeLog?rev=HEAD>

  <http://cvs.sourceforge.net/viewcvs.py/ctypes/ctypes/win32/com/ChangeLog?rev=HEAD>


Future plans

    The ultimate purpose of the 0.9 release series is to shake out the
    remaining bugs, especially on platforms I have no access to, and
    to target a rock stable ctypes 1.0 release.

    When ctypes 1.0 is released, the com framework will be split off
    into a separate framework named 'comtypes'.


Download

    Downloads are available in the sourceforge files section
    <http://sourceforge.net/project/showfiles.php?group_id=71702>

    Separate source distributions are available for windows and non-windows systems.
    Please use the .zip file for Windows (it contains the ctypes.com framework),
    and use the .tar.gz file for non-Windows systems (it contains the
    complete cross-platform libffi sources).

    Binary windows installers, which contain compiled extension
    modules, are also available, be sure to download the correct one
    for the Python version you are using.


Homepage

    <http://starship.python.net/crew/theller/ctypes/>

Enjoy,

Thomas