forked from AFPy/python-docs-fr
2524 lines
84 KiB
Plaintext
2524 lines
84 KiB
Plaintext
# SOME DESCRIPTIVE TITLE.
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# Copyright (C) 1990-2016, Python Software Foundation
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# This file is distributed under the same license as the Python package.
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# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
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#
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#, fuzzy
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msgid ""
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msgstr ""
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"Project-Id-Version: Python 2.7\n"
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"Report-Msgid-Bugs-To: \n"
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"POT-Creation-Date: 2016-10-30 10:44+0100\n"
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"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
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"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
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"Language-Team: LANGUAGE <LL@li.org>\n"
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"MIME-Version: 1.0\n"
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"Content-Type: text/plain; charset=UTF-8\n"
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"Content-Transfer-Encoding: 8bit\n"
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#: ../Doc/library/ctypes.rst:2
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msgid ":mod:`ctypes` --- A foreign function library for Python"
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msgstr ""
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#: ../Doc/library/ctypes.rst:11
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msgid ""
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":mod:`ctypes` is a foreign function library for Python. It provides C "
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"compatible data types, and allows calling functions in DLLs or shared "
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"libraries. It can be used to wrap these libraries in pure Python."
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msgstr ""
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#: ../Doc/library/ctypes.rst:19
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msgid "ctypes tutorial"
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msgstr ""
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#: ../Doc/library/ctypes.rst:21
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msgid ""
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"Note: The code samples in this tutorial use :mod:`doctest` to make sure that "
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"they actually work. Since some code samples behave differently under Linux, "
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"Windows, or Mac OS X, they contain doctest directives in comments."
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msgstr ""
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#: ../Doc/library/ctypes.rst:25
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msgid ""
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"Note: Some code samples reference the ctypes :class:`c_int` type. This type "
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"is an alias for the :class:`c_long` type on 32-bit systems. So, you should "
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"not be confused if :class:`c_long` is printed if you would expect :class:"
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"`c_int` --- they are actually the same type."
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msgstr ""
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#: ../Doc/library/ctypes.rst:34
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msgid "Loading dynamic link libraries"
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msgstr ""
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#: ../Doc/library/ctypes.rst:36
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msgid ""
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":mod:`ctypes` exports the *cdll*, and on Windows *windll* and *oledll* "
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"objects, for loading dynamic link libraries."
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msgstr ""
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#: ../Doc/library/ctypes.rst:39
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msgid ""
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"You load libraries by accessing them as attributes of these objects. *cdll* "
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"loads libraries which export functions using the standard ``cdecl`` calling "
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"convention, while *windll* libraries call functions using the ``stdcall`` "
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"calling convention. *oledll* also uses the ``stdcall`` calling convention, "
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"and assumes the functions return a Windows :c:type:`HRESULT` error code. The "
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"error code is used to automatically raise a :class:`WindowsError` exception "
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"when the function call fails."
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msgstr ""
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#: ../Doc/library/ctypes.rst:47
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msgid ""
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"Here are some examples for Windows. Note that ``msvcrt`` is the MS standard "
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"C library containing most standard C functions, and uses the cdecl calling "
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"convention::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:59
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msgid "Windows appends the usual ``.dll`` file suffix automatically."
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msgstr ""
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#: ../Doc/library/ctypes.rst:61
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msgid ""
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"On Linux, it is required to specify the filename *including* the extension "
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"to load a library, so attribute access can not be used to load libraries. "
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"Either the :meth:`LoadLibrary` method of the dll loaders should be used, or "
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"you should load the library by creating an instance of CDLL by calling the "
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"constructor::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:79
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msgid "Accessing functions from loaded dlls"
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msgstr ""
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#: ../Doc/library/ctypes.rst:81
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msgid "Functions are accessed as attributes of dll objects::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:96
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msgid ""
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"Note that win32 system dlls like ``kernel32`` and ``user32`` often export "
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"ANSI as well as UNICODE versions of a function. The UNICODE version is "
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"exported with an ``W`` appended to the name, while the ANSI version is "
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"exported with an ``A`` appended to the name. The win32 ``GetModuleHandle`` "
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"function, which returns a *module handle* for a given module name, has the "
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"following C prototype, and a macro is used to expose one of them as "
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"``GetModuleHandle`` depending on whether UNICODE is defined or not::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:109
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msgid ""
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"*windll* does not try to select one of them by magic, you must access the "
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"version you need by specifying ``GetModuleHandleA`` or ``GetModuleHandleW`` "
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"explicitly, and then call it with strings or unicode strings respectively."
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msgstr ""
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#: ../Doc/library/ctypes.rst:114
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msgid ""
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"Sometimes, dlls export functions with names which aren't valid Python "
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"identifiers, like ``\"??2@YAPAXI@Z\"``. In this case you have to use :func:"
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"`getattr` to retrieve the function::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:122
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msgid ""
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"On Windows, some dlls export functions not by name but by ordinal. These "
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"functions can be accessed by indexing the dll object with the ordinal "
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"number::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:139
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msgid "Calling functions"
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msgstr ""
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#: ../Doc/library/ctypes.rst:141
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msgid ""
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"You can call these functions like any other Python callable. This example "
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"uses the ``time()`` function, which returns system time in seconds since the "
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"Unix epoch, and the ``GetModuleHandleA()`` function, which returns a win32 "
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"module handle."
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msgstr ""
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#: ../Doc/library/ctypes.rst:146
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msgid ""
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"This example calls both functions with a NULL pointer (``None`` should be "
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"used as the NULL pointer)::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:155
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msgid ""
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":mod:`ctypes` tries to protect you from calling functions with the wrong "
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"number of arguments or the wrong calling convention. Unfortunately this "
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"only works on Windows. It does this by examining the stack after the "
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"function returns, so although an error is raised the function *has* been "
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"called::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:170
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msgid ""
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"The same exception is raised when you call an ``stdcall`` function with the "
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"``cdecl`` calling convention, or vice versa::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:185
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msgid ""
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"To find out the correct calling convention you have to look into the C "
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"header file or the documentation for the function you want to call."
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msgstr ""
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#: ../Doc/library/ctypes.rst:188
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msgid ""
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"On Windows, :mod:`ctypes` uses win32 structured exception handling to "
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"prevent crashes from general protection faults when functions are called "
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"with invalid argument values::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:198
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msgid ""
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"There are, however, enough ways to crash Python with :mod:`ctypes`, so you "
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"should be careful anyway."
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msgstr ""
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#: ../Doc/library/ctypes.rst:201
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msgid ""
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"``None``, integers, longs, byte strings and unicode strings are the only "
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"native Python objects that can directly be used as parameters in these "
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"function calls. ``None`` is passed as a C ``NULL`` pointer, byte strings and "
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"unicode strings are passed as pointer to the memory block that contains "
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"their data (:c:type:`char *` or :c:type:`wchar_t *`). Python integers and "
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"Python longs are passed as the platforms default C :c:type:`int` type, their "
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"value is masked to fit into the C type."
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msgstr ""
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#: ../Doc/library/ctypes.rst:209
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msgid ""
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"Before we move on calling functions with other parameter types, we have to "
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"learn more about :mod:`ctypes` data types."
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msgstr ""
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#: ../Doc/library/ctypes.rst:216 ../Doc/library/ctypes.rst:2142
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msgid "Fundamental data types"
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msgstr ""
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#: ../Doc/library/ctypes.rst:218
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msgid ":mod:`ctypes` defines a number of primitive C compatible data types:"
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msgstr ""
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#: ../Doc/library/ctypes.rst:221
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msgid "ctypes type"
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msgstr "Type *ctype*"
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#: ../Doc/library/ctypes.rst:221
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msgid "C type"
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msgstr "Type C"
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#: ../Doc/library/ctypes.rst:221
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msgid "Python type"
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msgstr "Type Python"
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#: ../Doc/library/ctypes.rst:223
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msgid ":class:`c_bool`"
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msgstr ":class:`c_bool`"
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#: ../Doc/library/ctypes.rst:223
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msgid ":c:type:`_Bool`"
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msgstr ":c:type:`_Bool`"
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#: ../Doc/library/ctypes.rst:223
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msgid "bool (1)"
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msgstr "bool (1)"
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#: ../Doc/library/ctypes.rst:225
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msgid ":class:`c_char`"
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msgstr ":class:`c_char`"
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#: ../Doc/library/ctypes.rst:225 ../Doc/library/ctypes.rst:229
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msgid ":c:type:`char`"
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msgstr ":c:type:`char`"
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#: ../Doc/library/ctypes.rst:225
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msgid "1-character string"
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msgstr ""
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#: ../Doc/library/ctypes.rst:227
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msgid ":class:`c_wchar`"
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msgstr ":class:`c_wchar`"
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#: ../Doc/library/ctypes.rst:227
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msgid ":c:type:`wchar_t`"
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msgstr ":c:type:`wchar_t`"
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#: ../Doc/library/ctypes.rst:227
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msgid "1-character unicode string"
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msgstr ""
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#: ../Doc/library/ctypes.rst:229
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msgid ":class:`c_byte`"
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msgstr ":class:`c_byte`"
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#: ../Doc/library/ctypes.rst:229 ../Doc/library/ctypes.rst:231
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#: ../Doc/library/ctypes.rst:233 ../Doc/library/ctypes.rst:235
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#: ../Doc/library/ctypes.rst:237 ../Doc/library/ctypes.rst:239
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#: ../Doc/library/ctypes.rst:241 ../Doc/library/ctypes.rst:243
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#: ../Doc/library/ctypes.rst:245 ../Doc/library/ctypes.rst:247
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msgid "int/long"
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msgstr ""
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#: ../Doc/library/ctypes.rst:231
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msgid ":class:`c_ubyte`"
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msgstr ":class:`c_ubyte`"
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#: ../Doc/library/ctypes.rst:231
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msgid ":c:type:`unsigned char`"
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msgstr ":c:type:`unsigned char`"
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#: ../Doc/library/ctypes.rst:233
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msgid ":class:`c_short`"
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msgstr ":class:`c_short`"
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#: ../Doc/library/ctypes.rst:233
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msgid ":c:type:`short`"
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msgstr ":c:type:`short`"
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#: ../Doc/library/ctypes.rst:235
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msgid ":class:`c_ushort`"
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msgstr ":class:`c_ushort`"
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#: ../Doc/library/ctypes.rst:235
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msgid ":c:type:`unsigned short`"
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msgstr ":c:type:`unsigned short`"
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#: ../Doc/library/ctypes.rst:237
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msgid ":class:`c_int`"
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msgstr ":class:`c_int`"
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#: ../Doc/library/ctypes.rst:237
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msgid ":c:type:`int`"
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msgstr ":c:type:`int`"
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#: ../Doc/library/ctypes.rst:239
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msgid ":class:`c_uint`"
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msgstr ":class:`c_uint`"
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#: ../Doc/library/ctypes.rst:239
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msgid ":c:type:`unsigned int`"
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msgstr ":c:type:`unsigned int`"
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#: ../Doc/library/ctypes.rst:241
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msgid ":class:`c_long`"
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msgstr ":class:`c_long`"
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#: ../Doc/library/ctypes.rst:241
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msgid ":c:type:`long`"
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msgstr ":c:type:`long`"
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#: ../Doc/library/ctypes.rst:243
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msgid ":class:`c_ulong`"
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msgstr ":class:`c_ulong`"
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#: ../Doc/library/ctypes.rst:243
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msgid ":c:type:`unsigned long`"
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msgstr ":c:type:`unsigned long`"
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#: ../Doc/library/ctypes.rst:245
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msgid ":class:`c_longlong`"
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msgstr ":class:`c_longlong`"
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#: ../Doc/library/ctypes.rst:245
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msgid ":c:type:`__int64` or :c:type:`long long`"
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msgstr ":c:type:`__int64` ou :c:type:`long long`"
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#: ../Doc/library/ctypes.rst:247
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msgid ":class:`c_ulonglong`"
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msgstr ":class:`c_ulonglong`"
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#: ../Doc/library/ctypes.rst:247
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msgid ":c:type:`unsigned __int64` or :c:type:`unsigned long long`"
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msgstr ""
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#: ../Doc/library/ctypes.rst:250
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msgid ":class:`c_float`"
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msgstr ":class:`c_float`"
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#: ../Doc/library/ctypes.rst:250
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msgid ":c:type:`float`"
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msgstr ":c:type:`float`"
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#: ../Doc/library/ctypes.rst:250 ../Doc/library/ctypes.rst:252
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#: ../Doc/library/ctypes.rst:254
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msgid "float"
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msgstr "*float*"
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#: ../Doc/library/ctypes.rst:252
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msgid ":class:`c_double`"
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msgstr ":class:`c_double`"
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#: ../Doc/library/ctypes.rst:252
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msgid ":c:type:`double`"
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msgstr ":c:type:`double`"
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#: ../Doc/library/ctypes.rst:254
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msgid ":class:`c_longdouble`"
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msgstr ":class:`c_longdouble`"
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#: ../Doc/library/ctypes.rst:254
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msgid ":c:type:`long double`"
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msgstr ":c:type:`long double`"
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#: ../Doc/library/ctypes.rst:256
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msgid ":class:`c_char_p`"
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msgstr ":class:`c_char_p`"
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#: ../Doc/library/ctypes.rst:256
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msgid ":c:type:`char *` (NUL terminated)"
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msgstr ":c:type:`char *` (NUL terminated)"
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#: ../Doc/library/ctypes.rst:256
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msgid "string or ``None``"
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msgstr "string ou ``None``"
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#: ../Doc/library/ctypes.rst:258
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msgid ":class:`c_wchar_p`"
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msgstr ":class:`c_wchar_p`"
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#: ../Doc/library/ctypes.rst:258
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msgid ":c:type:`wchar_t *` (NUL terminated)"
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msgstr ":c:type:`wchar_t *` (Terminé par NUL)"
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#: ../Doc/library/ctypes.rst:258
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msgid "unicode or ``None``"
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msgstr ""
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#: ../Doc/library/ctypes.rst:260
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msgid ":class:`c_void_p`"
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msgstr ":class:`c_void_p`"
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#: ../Doc/library/ctypes.rst:260
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msgid ":c:type:`void *`"
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msgstr ":c:type:`void *`"
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#: ../Doc/library/ctypes.rst:260
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msgid "int/long or ``None``"
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msgstr ""
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#: ../Doc/library/ctypes.rst:264
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msgid "The constructor accepts any object with a truth value."
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msgstr ""
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#: ../Doc/library/ctypes.rst:266
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msgid ""
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"All these types can be created by calling them with an optional initializer "
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"of the correct type and value::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:277
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msgid ""
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"Since these types are mutable, their value can also be changed afterwards::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:289
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msgid ""
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"Assigning a new value to instances of the pointer types :class:`c_char_p`, :"
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"class:`c_wchar_p`, and :class:`c_void_p` changes the *memory location* they "
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"point to, *not the contents* of the memory block (of course not, because "
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"Python strings are immutable)::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:305
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msgid ""
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"You should be careful, however, not to pass them to functions expecting "
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"pointers to mutable memory. If you need mutable memory blocks, ctypes has a :"
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"func:`create_string_buffer` function which creates these in various ways. "
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"The current memory block contents can be accessed (or changed) with the "
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"``raw`` property; if you want to access it as NUL terminated string, use the "
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"``value`` property::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:329
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msgid ""
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"The :func:`create_string_buffer` function replaces the :func:`c_buffer` "
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"function (which is still available as an alias), as well as the :func:"
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"`c_string` function from earlier ctypes releases. To create a mutable "
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"memory block containing unicode characters of the C type :c:type:`wchar_t` "
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"use the :func:`create_unicode_buffer` function."
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msgstr ""
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#: ../Doc/library/ctypes.rst:339
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msgid "Calling functions, continued"
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msgstr ""
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#: ../Doc/library/ctypes.rst:341
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msgid ""
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"Note that printf prints to the real standard output channel, *not* to :data:"
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"`sys.stdout`, so these examples will only work at the console prompt, not "
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"from within *IDLE* or *PythonWin*::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:361
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msgid ""
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"As has been mentioned before, all Python types except integers, strings, and "
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"unicode strings have to be wrapped in their corresponding :mod:`ctypes` "
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"type, so that they can be converted to the required C data type::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:374
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msgid "Calling functions with your own custom data types"
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msgstr ""
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#: ../Doc/library/ctypes.rst:376
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msgid ""
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"You can also customize :mod:`ctypes` argument conversion to allow instances "
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"of your own classes be used as function arguments. :mod:`ctypes` looks for "
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"an :attr:`_as_parameter_` attribute and uses this as the function argument. "
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"Of course, it must be one of integer, string, or unicode::"
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msgstr ""
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#: ../Doc/library/ctypes.rst:391
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msgid ""
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"If you don't want to store the instance's data in the :attr:`_as_parameter_` "
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"instance variable, you could define a :func:`property` which makes the data "
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"available."
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msgstr ""
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#: ../Doc/library/ctypes.rst:399
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msgid "Specifying the required argument types (function prototypes)"
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msgstr ""
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#: ../Doc/library/ctypes.rst:401
|
|
msgid ""
|
|
"It is possible to specify the required argument types of functions exported "
|
|
"from DLLs by setting the :attr:`argtypes` attribute."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:404
|
|
msgid ""
|
|
":attr:`argtypes` must be a sequence of C data types (the ``printf`` function "
|
|
"is probably not a good example here, because it takes a variable number and "
|
|
"different types of parameters depending on the format string, on the other "
|
|
"hand this is quite handy to experiment with this feature)::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:415
|
|
msgid ""
|
|
"Specifying a format protects against incompatible argument types (just as a "
|
|
"prototype for a C function), and tries to convert the arguments to valid "
|
|
"types::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:427
|
|
msgid ""
|
|
"If you have defined your own classes which you pass to function calls, you "
|
|
"have to implement a :meth:`from_param` class method for them to be able to "
|
|
"use them in the :attr:`argtypes` sequence. The :meth:`from_param` class "
|
|
"method receives the Python object passed to the function call, it should do "
|
|
"a typecheck or whatever is needed to make sure this object is acceptable, "
|
|
"and then return the object itself, its :attr:`_as_parameter_` attribute, or "
|
|
"whatever you want to pass as the C function argument in this case. Again, "
|
|
"the result should be an integer, string, unicode, a :mod:`ctypes` instance, "
|
|
"or an object with an :attr:`_as_parameter_` attribute."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:441
|
|
msgid "Return types"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:443
|
|
msgid ""
|
|
"By default functions are assumed to return the C :c:type:`int` type. Other "
|
|
"return types can be specified by setting the :attr:`restype` attribute of "
|
|
"the function object."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:447
|
|
msgid ""
|
|
"Here is a more advanced example, it uses the ``strchr`` function, which "
|
|
"expects a string pointer and a char, and returns a pointer to a string::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:460
|
|
msgid ""
|
|
"If you want to avoid the ``ord(\"x\")`` calls above, you can set the :attr:"
|
|
"`argtypes` attribute, and the second argument will be converted from a "
|
|
"single character Python string into a C char::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:478
|
|
msgid ""
|
|
"You can also use a callable Python object (a function or a class for "
|
|
"example) as the :attr:`restype` attribute, if the foreign function returns "
|
|
"an integer. The callable will be called with the *integer* the C function "
|
|
"returns, and the result of this call will be used as the result of your "
|
|
"function call. This is useful to check for error return values and "
|
|
"automatically raise an exception::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:501
|
|
msgid ""
|
|
"``WinError`` is a function which will call Windows ``FormatMessage()`` api "
|
|
"to get the string representation of an error code, and *returns* an "
|
|
"exception. ``WinError`` takes an optional error code parameter, if no one is "
|
|
"used, it calls :func:`GetLastError` to retrieve it."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:506
|
|
msgid ""
|
|
"Please note that a much more powerful error checking mechanism is available "
|
|
"through the :attr:`errcheck` attribute; see the reference manual for details."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:513
|
|
msgid "Passing pointers (or: passing parameters by reference)"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:515
|
|
msgid ""
|
|
"Sometimes a C api function expects a *pointer* to a data type as parameter, "
|
|
"probably to write into the corresponding location, or if the data is too "
|
|
"large to be passed by value. This is also known as *passing parameters by "
|
|
"reference*."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:519
|
|
msgid ""
|
|
":mod:`ctypes` exports the :func:`byref` function which is used to pass "
|
|
"parameters by reference. The same effect can be achieved with the :func:"
|
|
"`pointer` function, although :func:`pointer` does a lot more work since it "
|
|
"constructs a real pointer object, so it is faster to use :func:`byref` if "
|
|
"you don't need the pointer object in Python itself::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:541
|
|
msgid "Structures and unions"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:543
|
|
msgid ""
|
|
"Structures and unions must derive from the :class:`Structure` and :class:"
|
|
"`Union` base classes which are defined in the :mod:`ctypes` module. Each "
|
|
"subclass must define a :attr:`_fields_` attribute. :attr:`_fields_` must be "
|
|
"a list of *2-tuples*, containing a *field name* and a *field type*."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:548
|
|
msgid ""
|
|
"The field type must be a :mod:`ctypes` type like :class:`c_int`, or any "
|
|
"other derived :mod:`ctypes` type: structure, union, array, pointer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:551
|
|
msgid ""
|
|
"Here is a simple example of a POINT structure, which contains two integers "
|
|
"named *x* and *y*, and also shows how to initialize a structure in the "
|
|
"constructor::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:571
|
|
msgid ""
|
|
"You can, however, build much more complicated structures. A structure can "
|
|
"itself contain other structures by using a structure as a field type."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:574
|
|
msgid ""
|
|
"Here is a RECT structure which contains two POINTs named *upperleft* and "
|
|
"*lowerright*::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:588
|
|
msgid ""
|
|
"Nested structures can also be initialized in the constructor in several "
|
|
"ways::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:593
|
|
msgid ""
|
|
"Field :term:`descriptor`\\s can be retrieved from the *class*, they are "
|
|
"useful for debugging because they can provide useful information::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:607
|
|
msgid ""
|
|
":mod:`ctypes` does not support passing unions or structures with bit-fields "
|
|
"to functions by value. While this may work on 32-bit x86, it's not "
|
|
"guaranteed by the library to work in the general case. Unions and "
|
|
"structures with bit-fields should always be passed to functions by pointer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:613
|
|
msgid "Structure/union alignment and byte order"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:615
|
|
msgid ""
|
|
"By default, Structure and Union fields are aligned in the same way the C "
|
|
"compiler does it. It is possible to override this behavior be specifying a :"
|
|
"attr:`_pack_` class attribute in the subclass definition. This must be set "
|
|
"to a positive integer and specifies the maximum alignment for the fields. "
|
|
"This is what ``#pragma pack(n)`` also does in MSVC."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:621
|
|
msgid ""
|
|
":mod:`ctypes` uses the native byte order for Structures and Unions. To "
|
|
"build structures with non-native byte order, you can use one of the :class:"
|
|
"`BigEndianStructure`, :class:`LittleEndianStructure`, :class:"
|
|
"`BigEndianUnion`, and :class:`LittleEndianUnion` base classes. These "
|
|
"classes cannot contain pointer fields."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:631
|
|
msgid "Bit fields in structures and unions"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:633
|
|
msgid ""
|
|
"It is possible to create structures and unions containing bit fields. Bit "
|
|
"fields are only possible for integer fields, the bit width is specified as "
|
|
"the third item in the :attr:`_fields_` tuples::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:651
|
|
msgid "Arrays"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:653
|
|
msgid ""
|
|
"Arrays are sequences, containing a fixed number of instances of the same "
|
|
"type."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:655
|
|
msgid ""
|
|
"The recommended way to create array types is by multiplying a data type with "
|
|
"a positive integer::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:660
|
|
msgid ""
|
|
"Here is an example of a somewhat artificial data type, a structure "
|
|
"containing 4 POINTs among other stuff::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:676
|
|
msgid "Instances are created in the usual way, by calling the class::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:682
|
|
msgid ""
|
|
"The above code print a series of ``0 0`` lines, because the array contents "
|
|
"is initialized to zeros."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:685
|
|
msgid "Initializers of the correct type can also be specified::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:701
|
|
msgid "Pointers"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:703
|
|
msgid ""
|
|
"Pointer instances are created by calling the :func:`pointer` function on a :"
|
|
"mod:`ctypes` type::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:711
|
|
msgid ""
|
|
"Pointer instances have a :attr:`~_Pointer.contents` attribute which returns "
|
|
"the object to which the pointer points, the ``i`` object above::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:718
|
|
msgid ""
|
|
"Note that :mod:`ctypes` does not have OOR (original object return), it "
|
|
"constructs a new, equivalent object each time you retrieve an attribute::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:727
|
|
msgid ""
|
|
"Assigning another :class:`c_int` instance to the pointer's contents "
|
|
"attribute would cause the pointer to point to the memory location where this "
|
|
"is stored::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:739
|
|
msgid "Pointer instances can also be indexed with integers::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:745
|
|
msgid "Assigning to an integer index changes the pointed to value::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:754
|
|
msgid ""
|
|
"It is also possible to use indexes different from 0, but you must know what "
|
|
"you're doing, just as in C: You can access or change arbitrary memory "
|
|
"locations. Generally you only use this feature if you receive a pointer from "
|
|
"a C function, and you *know* that the pointer actually points to an array "
|
|
"instead of a single item."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:760
|
|
msgid ""
|
|
"Behind the scenes, the :func:`pointer` function does more than simply create "
|
|
"pointer instances, it has to create pointer *types* first. This is done "
|
|
"with the :func:`POINTER` function, which accepts any :mod:`ctypes` type, and "
|
|
"returns a new type::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:776
|
|
msgid ""
|
|
"Calling the pointer type without an argument creates a ``NULL`` pointer. "
|
|
"``NULL`` pointers have a ``False`` boolean value::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:784
|
|
msgid ""
|
|
":mod:`ctypes` checks for ``NULL`` when dereferencing pointers (but "
|
|
"dereferencing invalid non-\\ ``NULL`` pointers would crash Python)::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:803
|
|
msgid "Type conversions"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:805
|
|
msgid ""
|
|
"Usually, ctypes does strict type checking. This means, if you have "
|
|
"``POINTER(c_int)`` in the :attr:`argtypes` list of a function or as the type "
|
|
"of a member field in a structure definition, only instances of exactly the "
|
|
"same type are accepted. There are some exceptions to this rule, where "
|
|
"ctypes accepts other objects. For example, you can pass compatible array "
|
|
"instances instead of pointer types. So, for ``POINTER(c_int)``, ctypes "
|
|
"accepts an array of c_int::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:826
|
|
msgid ""
|
|
"In addition, if a function argument is explicitly declared to be a pointer "
|
|
"type (such as ``POINTER(c_int)``) in :attr:`argtypes`, an object of the "
|
|
"pointed type (``c_int`` in this case) can be passed to the function. ctypes "
|
|
"will apply the required :func:`byref` conversion in this case automatically."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:831
|
|
msgid "To set a POINTER type field to ``NULL``, you can assign ``None``::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:838
|
|
msgid ""
|
|
"Sometimes you have instances of incompatible types. In C, you can cast one "
|
|
"type into another type. :mod:`ctypes` provides a :func:`cast` function "
|
|
"which can be used in the same way. The ``Bar`` structure defined above "
|
|
"accepts ``POINTER(c_int)`` pointers or :class:`c_int` arrays for its "
|
|
"``values`` field, but not instances of other types::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:850
|
|
msgid "For these cases, the :func:`cast` function is handy."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:852
|
|
msgid ""
|
|
"The :func:`cast` function can be used to cast a ctypes instance into a "
|
|
"pointer to a different ctypes data type. :func:`cast` takes two parameters, "
|
|
"a ctypes object that is or can be converted to a pointer of some kind, and a "
|
|
"ctypes pointer type. It returns an instance of the second argument, which "
|
|
"references the same memory block as the first argument::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:863
|
|
msgid ""
|
|
"So, :func:`cast` can be used to assign to the ``values`` field of ``Bar`` "
|
|
"the structure::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:876
|
|
msgid "Incomplete Types"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:878
|
|
msgid ""
|
|
"*Incomplete Types* are structures, unions or arrays whose members are not "
|
|
"yet specified. In C, they are specified by forward declarations, which are "
|
|
"defined later::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:889
|
|
msgid ""
|
|
"The straightforward translation into ctypes code would be this, but it does "
|
|
"not work::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:902
|
|
msgid ""
|
|
"because the new ``class cell`` is not available in the class statement "
|
|
"itself. In :mod:`ctypes`, we can define the ``cell`` class and set the :attr:"
|
|
"`_fields_` attribute later, after the class statement::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:914
|
|
msgid ""
|
|
"Lets try it. We create two instances of ``cell``, and let them point to each "
|
|
"other, and finally follow the pointer chain a few times::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:935
|
|
msgid "Callback functions"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:937
|
|
msgid ""
|
|
":mod:`ctypes` allows creating C callable function pointers from Python "
|
|
"callables. These are sometimes called *callback functions*."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:940
|
|
msgid ""
|
|
"First, you must create a class for the callback function, the class knows "
|
|
"the calling convention, the return type, and the number and types of "
|
|
"arguments this function will receive."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:944
|
|
msgid ""
|
|
"The CFUNCTYPE factory function creates types for callback functions using "
|
|
"the normal cdecl calling convention, and, on Windows, the WINFUNCTYPE "
|
|
"factory function creates types for callback functions using the stdcall "
|
|
"calling convention."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:949
|
|
msgid ""
|
|
"Both of these factory functions are called with the result type as first "
|
|
"argument, and the callback functions expected argument types as the "
|
|
"remaining arguments."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:953
|
|
msgid ""
|
|
"I will present an example here which uses the standard C library's :func:"
|
|
"`qsort` function, this is used to sort items with the help of a callback "
|
|
"function. :func:`qsort` will be used to sort an array of integers::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:963
|
|
msgid ""
|
|
":func:`qsort` must be called with a pointer to the data to sort, the number "
|
|
"of items in the data array, the size of one item, and a pointer to the "
|
|
"comparison function, the callback. The callback will then be called with two "
|
|
"pointers to items, and it must return a negative integer if the first item "
|
|
"is smaller than the second, a zero if they are equal, and a positive integer "
|
|
"else."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:969
|
|
msgid ""
|
|
"So our callback function receives pointers to integers, and must return an "
|
|
"integer. First we create the ``type`` for the callback function::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:975
|
|
msgid ""
|
|
"For the first implementation of the callback function, we simply print the "
|
|
"arguments we get, and return 0 (incremental development ;-)::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:984
|
|
msgid "Create the C callable callback::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:989
|
|
msgid "And we're ready to go::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1004
|
|
msgid ""
|
|
"We know how to access the contents of a pointer, so lets redefine our "
|
|
"callback::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1013
|
|
msgid "Here is what we get on Windows::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1028
|
|
msgid ""
|
|
"It is funny to see that on linux the sort function seems to work much more "
|
|
"efficiently, it is doing less comparisons::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1039
|
|
msgid ""
|
|
"Ah, we're nearly done! The last step is to actually compare the two items "
|
|
"and return a useful result::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1048
|
|
msgid "Final run on Windows::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1063
|
|
msgid "and on Linux::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1073
|
|
msgid ""
|
|
"It is quite interesting to see that the Windows :func:`qsort` function needs "
|
|
"more comparisons than the linux version!"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1076
|
|
msgid "As we can easily check, our array is sorted now::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1085
|
|
msgid ""
|
|
"Make sure you keep references to :func:`CFUNCTYPE` objects as long as they "
|
|
"are used from C code. :mod:`ctypes` doesn't, and if you don't, they may be "
|
|
"garbage collected, crashing your program when a callback is made."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1089
|
|
msgid ""
|
|
"Also, note that if the callback function is called in a thread created "
|
|
"outside of Python's control (e.g. by the foreign code that calls the "
|
|
"callback), ctypes creates a new dummy Python thread on every invocation. "
|
|
"This behavior is correct for most purposes, but it means that values stored "
|
|
"with :class:`threading.local` will *not* survive across different callbacks, "
|
|
"even when those calls are made from the same C thread."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1099
|
|
msgid "Accessing values exported from dlls"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1101
|
|
msgid ""
|
|
"Some shared libraries not only export functions, they also export variables. "
|
|
"An example in the Python library itself is the ``Py_OptimizeFlag``, an "
|
|
"integer set to 0, 1, or 2, depending on the :option:`-O` or :option:`-OO` "
|
|
"flag given on startup."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1106
|
|
msgid ""
|
|
":mod:`ctypes` can access values like this with the :meth:`in_dll` class "
|
|
"methods of the type. *pythonapi* is a predefined symbol giving access to "
|
|
"the Python C api::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1115
|
|
msgid ""
|
|
"If the interpreter would have been started with :option:`-O`, the sample "
|
|
"would have printed ``c_long(1)``, or ``c_long(2)`` if :option:`-OO` would "
|
|
"have been specified."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1119
|
|
msgid ""
|
|
"An extended example which also demonstrates the use of pointers accesses the "
|
|
"``PyImport_FrozenModules`` pointer exported by Python."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1122
|
|
msgid ""
|
|
"Quoting the Python docs: *This pointer is initialized to point to an array "
|
|
"of \"struct _frozen\" records, terminated by one whose members are all NULL "
|
|
"or zero. When a frozen module is imported, it is searched in this table. "
|
|
"Third-party code could play tricks with this to provide a dynamically "
|
|
"created collection of frozen modules.*"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1128
|
|
msgid ""
|
|
"So manipulating this pointer could even prove useful. To restrict the "
|
|
"example size, we show only how this table can be read with :mod:`ctypes`::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1140
|
|
msgid ""
|
|
"We have defined the ``struct _frozen`` data type, so we can get the pointer "
|
|
"to the table::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1147
|
|
msgid ""
|
|
"Since ``table`` is a ``pointer`` to the array of ``struct_frozen`` records, "
|
|
"we can iterate over it, but we just have to make sure that our loop "
|
|
"terminates, because pointers have no size. Sooner or later it would probably "
|
|
"crash with an access violation or whatever, so it's better to break out of "
|
|
"the loop when we hit the NULL entry::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1164
|
|
msgid ""
|
|
"The fact that standard Python has a frozen module and a frozen package "
|
|
"(indicated by the negative size member) is not well known, it is only used "
|
|
"for testing. Try it out with ``import __hello__`` for example."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1172
|
|
msgid "Surprises"
|
|
msgstr "Surprises"
|
|
|
|
#: ../Doc/library/ctypes.rst:1174
|
|
msgid ""
|
|
"There are some edge cases in :mod:`ctypes` where you might expect something "
|
|
"other than what actually happens."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1177
|
|
msgid "Consider the following example::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1197
|
|
msgid ""
|
|
"Hm. We certainly expected the last statement to print ``3 4 1 2``. What "
|
|
"happened? Here are the steps of the ``rc.a, rc.b = rc.b, rc.a`` line above::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1205
|
|
msgid ""
|
|
"Note that ``temp0`` and ``temp1`` are objects still using the internal "
|
|
"buffer of the ``rc`` object above. So executing ``rc.a = temp0`` copies the "
|
|
"buffer contents of ``temp0`` into ``rc`` 's buffer. This, in turn, changes "
|
|
"the contents of ``temp1``. So, the last assignment ``rc.b = temp1``, doesn't "
|
|
"have the expected effect."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1211
|
|
msgid ""
|
|
"Keep in mind that retrieving sub-objects from Structure, Unions, and Arrays "
|
|
"doesn't *copy* the sub-object, instead it retrieves a wrapper object "
|
|
"accessing the root-object's underlying buffer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1215
|
|
msgid ""
|
|
"Another example that may behave different from what one would expect is "
|
|
"this::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1225
|
|
msgid ""
|
|
"Why is it printing ``False``? ctypes instances are objects containing a "
|
|
"memory block plus some :term:`descriptor`\\s accessing the contents of the "
|
|
"memory. Storing a Python object in the memory block does not store the "
|
|
"object itself, instead the ``contents`` of the object is stored. Accessing "
|
|
"the contents again constructs a new Python object each time!"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1235
|
|
msgid "Variable-sized data types"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1237
|
|
msgid ""
|
|
":mod:`ctypes` provides some support for variable-sized arrays and structures."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1239
|
|
msgid ""
|
|
"The :func:`resize` function can be used to resize the memory buffer of an "
|
|
"existing ctypes object. The function takes the object as first argument, "
|
|
"and the requested size in bytes as the second argument. The memory block "
|
|
"cannot be made smaller than the natural memory block specified by the "
|
|
"objects type, a :exc:`ValueError` is raised if this is tried::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1259
|
|
msgid ""
|
|
"This is nice and fine, but how would one access the additional elements "
|
|
"contained in this array? Since the type still only knows about 4 elements, "
|
|
"we get errors accessing other elements::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1271
|
|
msgid ""
|
|
"Another way to use variable-sized data types with :mod:`ctypes` is to use "
|
|
"the dynamic nature of Python, and (re-)define the data type after the "
|
|
"required size is already known, on a case by case basis."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1279
|
|
msgid "ctypes reference"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1285
|
|
msgid "Finding shared libraries"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1287
|
|
msgid ""
|
|
"When programming in a compiled language, shared libraries are accessed when "
|
|
"compiling/linking a program, and when the program is run."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1290
|
|
msgid ""
|
|
"The purpose of the :func:`find_library` function is to locate a library in a "
|
|
"way similar to what the compiler does (on platforms with several versions of "
|
|
"a shared library the most recent should be loaded), while the ctypes library "
|
|
"loaders act like when a program is run, and call the runtime loader directly."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1295
|
|
msgid ""
|
|
"The :mod:`ctypes.util` module provides a function which can help to "
|
|
"determine the library to load."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1303
|
|
msgid ""
|
|
"Try to find a library and return a pathname. *name* is the library name "
|
|
"without any prefix like *lib*, suffix like ``.so``, ``.dylib`` or version "
|
|
"number (this is the form used for the posix linker option :option:`-l`). If "
|
|
"no library can be found, returns ``None``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1308 ../Doc/library/ctypes.rst:1903
|
|
msgid "The exact functionality is system dependent."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1310
|
|
msgid ""
|
|
"On Linux, :func:`find_library` tries to run external programs (``/sbin/"
|
|
"ldconfig``, ``gcc``, and ``objdump``) to find the library file. It returns "
|
|
"the filename of the library file. Here are some examples::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1323
|
|
msgid ""
|
|
"On OS X, :func:`find_library` tries several predefined naming schemes and "
|
|
"paths to locate the library, and returns a full pathname if successful::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1337
|
|
msgid ""
|
|
"On Windows, :func:`find_library` searches along the system search path, and "
|
|
"returns the full pathname, but since there is no predefined naming scheme a "
|
|
"call like ``find_library(\"c\")`` will fail and return ``None``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1341
|
|
msgid ""
|
|
"If wrapping a shared library with :mod:`ctypes`, it *may* be better to "
|
|
"determine the shared library name at development time, and hardcode that "
|
|
"into the wrapper module instead of using :func:`find_library` to locate the "
|
|
"library at runtime."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1349
|
|
msgid "Loading shared libraries"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1351
|
|
msgid ""
|
|
"There are several ways to load shared libraries into the Python process. "
|
|
"One way is to instantiate one of the following classes:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1357
|
|
msgid ""
|
|
"Instances of this class represent loaded shared libraries. Functions in "
|
|
"these libraries use the standard C calling convention, and are assumed to "
|
|
"return :c:type:`int`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1364
|
|
msgid ""
|
|
"Windows only: Instances of this class represent loaded shared libraries, "
|
|
"functions in these libraries use the ``stdcall`` calling convention, and are "
|
|
"assumed to return the windows specific :class:`HRESULT` code. :class:"
|
|
"`HRESULT` values contain information specifying whether the function call "
|
|
"failed or succeeded, together with additional error code. If the return "
|
|
"value signals a failure, an :class:`WindowsError` is automatically raised."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1374
|
|
msgid ""
|
|
"Windows only: Instances of this class represent loaded shared libraries, "
|
|
"functions in these libraries use the ``stdcall`` calling convention, and are "
|
|
"assumed to return :c:type:`int` by default."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1378
|
|
msgid ""
|
|
"On Windows CE only the standard calling convention is used, for convenience "
|
|
"the :class:`WinDLL` and :class:`OleDLL` use the standard calling convention "
|
|
"on this platform."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1382
|
|
msgid ""
|
|
"The Python :term:`global interpreter lock` is released before calling any "
|
|
"function exported by these libraries, and reacquired afterwards."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1388
|
|
msgid ""
|
|
"Instances of this class behave like :class:`CDLL` instances, except that the "
|
|
"Python GIL is *not* released during the function call, and after the "
|
|
"function execution the Python error flag is checked. If the error flag is "
|
|
"set, a Python exception is raised."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1393
|
|
msgid "Thus, this is only useful to call Python C api functions directly."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1395
|
|
msgid ""
|
|
"All these classes can be instantiated by calling them with at least one "
|
|
"argument, the pathname of the shared library. If you have an existing "
|
|
"handle to an already loaded shared library, it can be passed as the "
|
|
"``handle`` named parameter, otherwise the underlying platforms ``dlopen`` or "
|
|
"``LoadLibrary`` function is used to load the library into the process, and "
|
|
"to get a handle to it."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1402
|
|
msgid ""
|
|
"The *mode* parameter can be used to specify how the library is loaded. For "
|
|
"details, consult the :manpage:`dlopen(3)` manpage. On Windows, *mode* is "
|
|
"ignored. On posix systems, RTLD_NOW is always added, and is not "
|
|
"configurable."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1407
|
|
msgid ""
|
|
"The *use_errno* parameter, when set to true, enables a ctypes mechanism that "
|
|
"allows accessing the system :data:`errno` error number in a safe way. :mod:"
|
|
"`ctypes` maintains a thread-local copy of the systems :data:`errno` "
|
|
"variable; if you call foreign functions created with ``use_errno=True`` then "
|
|
"the :data:`errno` value before the function call is swapped with the ctypes "
|
|
"private copy, the same happens immediately after the function call."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1414
|
|
msgid ""
|
|
"The function :func:`ctypes.get_errno` returns the value of the ctypes "
|
|
"private copy, and the function :func:`ctypes.set_errno` changes the ctypes "
|
|
"private copy to a new value and returns the former value."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1418
|
|
msgid ""
|
|
"The *use_last_error* parameter, when set to true, enables the same mechanism "
|
|
"for the Windows error code which is managed by the :func:`GetLastError` and :"
|
|
"func:`SetLastError` Windows API functions; :func:`ctypes.get_last_error` "
|
|
"and :func:`ctypes.set_last_error` are used to request and change the ctypes "
|
|
"private copy of the windows error code."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1424
|
|
msgid "The *use_last_error* and *use_errno* optional parameters were added."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1430
|
|
msgid ""
|
|
"Flag to use as *mode* parameter. On platforms where this flag is not "
|
|
"available, it is defined as the integer zero."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1437
|
|
msgid ""
|
|
"Flag to use as *mode* parameter. On platforms where this is not available, "
|
|
"it is the same as *RTLD_GLOBAL*."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1444
|
|
msgid ""
|
|
"The default mode which is used to load shared libraries. On OSX 10.3, this "
|
|
"is *RTLD_GLOBAL*, otherwise it is the same as *RTLD_LOCAL*."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1447
|
|
msgid ""
|
|
"Instances of these classes have no public methods. Functions exported by "
|
|
"the shared library can be accessed as attributes or by index. Please note "
|
|
"that accessing the function through an attribute caches the result and "
|
|
"therefore accessing it repeatedly returns the same object each time. On the "
|
|
"other hand, accessing it through an index returns a new object each time:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1458
|
|
msgid ""
|
|
"The following public attributes are available, their name starts with an "
|
|
"underscore to not clash with exported function names:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1464
|
|
msgid "The system handle used to access the library."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1469
|
|
msgid "The name of the library passed in the constructor."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1471
|
|
msgid ""
|
|
"Shared libraries can also be loaded by using one of the prefabricated "
|
|
"objects, which are instances of the :class:`LibraryLoader` class, either by "
|
|
"calling the :meth:`LoadLibrary` method, or by retrieving the library as "
|
|
"attribute of the loader instance."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1479
|
|
msgid ""
|
|
"Class which loads shared libraries. *dlltype* should be one of the :class:"
|
|
"`CDLL`, :class:`PyDLL`, :class:`WinDLL`, or :class:`OleDLL` types."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1482
|
|
msgid ""
|
|
":meth:`__getattr__` has special behavior: It allows loading a shared library "
|
|
"by accessing it as attribute of a library loader instance. The result is "
|
|
"cached, so repeated attribute accesses return the same library each time."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1489
|
|
msgid ""
|
|
"Load a shared library into the process and return it. This method always "
|
|
"returns a new instance of the library."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1492
|
|
msgid "These prefabricated library loaders are available:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1498
|
|
msgid "Creates :class:`CDLL` instances."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1504
|
|
msgid "Windows only: Creates :class:`WinDLL` instances."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1510
|
|
msgid "Windows only: Creates :class:`OleDLL` instances."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1516
|
|
msgid "Creates :class:`PyDLL` instances."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1518
|
|
msgid ""
|
|
"For accessing the C Python api directly, a ready-to-use Python shared "
|
|
"library object is available:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1525
|
|
msgid ""
|
|
"An instance of :class:`PyDLL` that exposes Python C API functions as "
|
|
"attributes. Note that all these functions are assumed to return C :c:type:"
|
|
"`int`, which is of course not always the truth, so you have to assign the "
|
|
"correct :attr:`restype` attribute to use these functions."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1534
|
|
msgid "Foreign functions"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1536
|
|
msgid ""
|
|
"As explained in the previous section, foreign functions can be accessed as "
|
|
"attributes of loaded shared libraries. The function objects created in this "
|
|
"way by default accept any number of arguments, accept any ctypes data "
|
|
"instances as arguments, and return the default result type specified by the "
|
|
"library loader. They are instances of a private class:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1545
|
|
msgid "Base class for C callable foreign functions."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1547
|
|
msgid ""
|
|
"Instances of foreign functions are also C compatible data types; they "
|
|
"represent C function pointers."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1550
|
|
msgid ""
|
|
"This behavior can be customized by assigning to special attributes of the "
|
|
"foreign function object."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1556
|
|
msgid ""
|
|
"Assign a ctypes type to specify the result type of the foreign function. Use "
|
|
"``None`` for :c:type:`void`, a function not returning anything."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1559
|
|
msgid ""
|
|
"It is possible to assign a callable Python object that is not a ctypes type, "
|
|
"in this case the function is assumed to return a C :c:type:`int`, and the "
|
|
"callable will be called with this integer, allowing further processing or "
|
|
"error checking. Using this is deprecated, for more flexible post processing "
|
|
"or error checking use a ctypes data type as :attr:`restype` and assign a "
|
|
"callable to the :attr:`errcheck` attribute."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1569
|
|
msgid ""
|
|
"Assign a tuple of ctypes types to specify the argument types that the "
|
|
"function accepts. Functions using the ``stdcall`` calling convention can "
|
|
"only be called with the same number of arguments as the length of this "
|
|
"tuple; functions using the C calling convention accept additional, "
|
|
"unspecified arguments as well."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1575
|
|
msgid ""
|
|
"When a foreign function is called, each actual argument is passed to the :"
|
|
"meth:`from_param` class method of the items in the :attr:`argtypes` tuple, "
|
|
"this method allows adapting the actual argument to an object that the "
|
|
"foreign function accepts. For example, a :class:`c_char_p` item in the :"
|
|
"attr:`argtypes` tuple will convert a unicode string passed as argument into "
|
|
"a byte string using ctypes conversion rules."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1582
|
|
msgid ""
|
|
"New: It is now possible to put items in argtypes which are not ctypes types, "
|
|
"but each item must have a :meth:`from_param` method which returns a value "
|
|
"usable as argument (integer, string, ctypes instance). This allows defining "
|
|
"adapters that can adapt custom objects as function parameters."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1590
|
|
msgid ""
|
|
"Assign a Python function or another callable to this attribute. The callable "
|
|
"will be called with three or more arguments:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1596
|
|
msgid ""
|
|
"*result* is what the foreign function returns, as specified by the :attr:"
|
|
"`restype` attribute."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1599
|
|
msgid ""
|
|
"*func* is the foreign function object itself, this allows reusing the same "
|
|
"callable object to check or post process the results of several functions."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1603
|
|
msgid ""
|
|
"*arguments* is a tuple containing the parameters originally passed to the "
|
|
"function call, this allows specializing the behavior on the arguments used."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1607
|
|
msgid ""
|
|
"The object that this function returns will be returned from the foreign "
|
|
"function call, but it can also check the result value and raise an exception "
|
|
"if the foreign function call failed."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1614
|
|
msgid ""
|
|
"This exception is raised when a foreign function call cannot convert one of "
|
|
"the passed arguments."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1621
|
|
msgid "Function prototypes"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1623
|
|
msgid ""
|
|
"Foreign functions can also be created by instantiating function prototypes. "
|
|
"Function prototypes are similar to function prototypes in C; they describe a "
|
|
"function (return type, argument types, calling convention) without defining "
|
|
"an implementation. The factory functions must be called with the desired "
|
|
"result type and the argument types of the function."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1632
|
|
msgid ""
|
|
"The returned function prototype creates functions that use the standard C "
|
|
"calling convention. The function will release the GIL during the call. If "
|
|
"*use_errno* is set to true, the ctypes private copy of the system :data:"
|
|
"`errno` variable is exchanged with the real :data:`errno` value before and "
|
|
"after the call; *use_last_error* does the same for the Windows error code."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1639
|
|
msgid "The optional *use_errno* and *use_last_error* parameters were added."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1645
|
|
msgid ""
|
|
"Windows only: The returned function prototype creates functions that use the "
|
|
"``stdcall`` calling convention, except on Windows CE where :func:"
|
|
"`WINFUNCTYPE` is the same as :func:`CFUNCTYPE`. The function will release "
|
|
"the GIL during the call. *use_errno* and *use_last_error* have the same "
|
|
"meaning as above."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1654
|
|
msgid ""
|
|
"The returned function prototype creates functions that use the Python "
|
|
"calling convention. The function will *not* release the GIL during the call."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1657
|
|
msgid ""
|
|
"Function prototypes created by these factory functions can be instantiated "
|
|
"in different ways, depending on the type and number of the parameters in the "
|
|
"call:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1665
|
|
msgid ""
|
|
"Returns a foreign function at the specified address which must be an integer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1672
|
|
msgid ""
|
|
"Create a C callable function (a callback function) from a Python *callable*."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1679
|
|
msgid ""
|
|
"Returns a foreign function exported by a shared library. *func_spec* must be "
|
|
"a 2-tuple ``(name_or_ordinal, library)``. The first item is the name of the "
|
|
"exported function as string, or the ordinal of the exported function as "
|
|
"small integer. The second item is the shared library instance."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1689
|
|
msgid ""
|
|
"Returns a foreign function that will call a COM method. *vtbl_index* is the "
|
|
"index into the virtual function table, a small non-negative integer. *name* "
|
|
"is name of the COM method. *iid* is an optional pointer to the interface "
|
|
"identifier which is used in extended error reporting."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1694
|
|
msgid ""
|
|
"COM methods use a special calling convention: They require a pointer to the "
|
|
"COM interface as first argument, in addition to those parameters that are "
|
|
"specified in the :attr:`argtypes` tuple."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1698
|
|
msgid ""
|
|
"The optional *paramflags* parameter creates foreign function wrappers with "
|
|
"much more functionality than the features described above."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1701
|
|
msgid "*paramflags* must be a tuple of the same length as :attr:`argtypes`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1703
|
|
msgid ""
|
|
"Each item in this tuple contains further information about a parameter, it "
|
|
"must be a tuple containing one, two, or three items."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1706
|
|
msgid ""
|
|
"The first item is an integer containing a combination of direction flags for "
|
|
"the parameter:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1710
|
|
msgid "1"
|
|
msgstr "1"
|
|
|
|
#: ../Doc/library/ctypes.rst:1710
|
|
msgid "Specifies an input parameter to the function."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1713
|
|
msgid "2"
|
|
msgstr "2"
|
|
|
|
#: ../Doc/library/ctypes.rst:1713
|
|
msgid "Output parameter. The foreign function fills in a value."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1716
|
|
msgid "4"
|
|
msgstr "4"
|
|
|
|
#: ../Doc/library/ctypes.rst:1716
|
|
msgid "Input parameter which defaults to the integer zero."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1718
|
|
msgid ""
|
|
"The optional second item is the parameter name as string. If this is "
|
|
"specified, the foreign function can be called with named parameters."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1721
|
|
msgid "The optional third item is the default value for this parameter."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1723
|
|
msgid ""
|
|
"This example demonstrates how to wrap the Windows ``MessageBoxA`` function "
|
|
"so that it supports default parameters and named arguments. The C "
|
|
"declaration from the windows header file is this::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1734 ../Doc/library/ctypes.rst:1759
|
|
msgid "Here is the wrapping with :mod:`ctypes`::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1743
|
|
msgid "The MessageBox foreign function can now be called in these ways::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1750
|
|
msgid ""
|
|
"A second example demonstrates output parameters. The win32 "
|
|
"``GetWindowRect`` function retrieves the dimensions of a specified window by "
|
|
"copying them into ``RECT`` structure that the caller has to supply. Here is "
|
|
"the C declaration::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1768
|
|
msgid ""
|
|
"Functions with output parameters will automatically return the output "
|
|
"parameter value if there is a single one, or a tuple containing the output "
|
|
"parameter values when there are more than one, so the GetWindowRect function "
|
|
"now returns a RECT instance, when called."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1773
|
|
msgid ""
|
|
"Output parameters can be combined with the :attr:`errcheck` protocol to do "
|
|
"further output processing and error checking. The win32 ``GetWindowRect`` "
|
|
"api function returns a ``BOOL`` to signal success or failure, so this "
|
|
"function could do the error checking, and raises an exception when the api "
|
|
"call failed::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1786
|
|
msgid ""
|
|
"If the :attr:`errcheck` function returns the argument tuple it receives "
|
|
"unchanged, :mod:`ctypes` continues the normal processing it does on the "
|
|
"output parameters. If you want to return a tuple of window coordinates "
|
|
"instead of a ``RECT`` instance, you can retrieve the fields in the function "
|
|
"and return them instead, the normal processing will no longer take place::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1805
|
|
msgid "Utility functions"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1810
|
|
msgid ""
|
|
"Returns the address of the memory buffer as integer. *obj* must be an "
|
|
"instance of a ctypes type."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1816
|
|
msgid ""
|
|
"Returns the alignment requirements of a ctypes type. *obj_or_type* must be a "
|
|
"ctypes type or instance."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1822
|
|
msgid ""
|
|
"Returns a light-weight pointer to *obj*, which must be an instance of a "
|
|
"ctypes type. *offset* defaults to zero, and must be an integer that will be "
|
|
"added to the internal pointer value."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1826
|
|
msgid "``byref(obj, offset)`` corresponds to this C code::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1830
|
|
msgid ""
|
|
"The returned object can only be used as a foreign function call parameter. "
|
|
"It behaves similar to ``pointer(obj)``, but the construction is a lot faster."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1834
|
|
msgid "The *offset* optional argument was added."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1840
|
|
msgid ""
|
|
"This function is similar to the cast operator in C. It returns a new "
|
|
"instance of *type* which points to the same memory block as *obj*. *type* "
|
|
"must be a pointer type, and *obj* must be an object that can be interpreted "
|
|
"as a pointer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1848
|
|
msgid ""
|
|
"This function creates a mutable character buffer. The returned object is a "
|
|
"ctypes array of :class:`c_char`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1851
|
|
msgid ""
|
|
"*init_or_size* must be an integer which specifies the size of the array, or "
|
|
"a string which will be used to initialize the array items."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1854
|
|
msgid ""
|
|
"If a string is specified as first argument, the buffer is made one item "
|
|
"larger than the length of the string so that the last element in the array "
|
|
"is a NUL termination character. An integer can be passed as second argument "
|
|
"which allows specifying the size of the array if the length of the string "
|
|
"should not be used."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1859
|
|
msgid ""
|
|
"If the first parameter is a unicode string, it is converted into an 8-bit "
|
|
"string according to ctypes conversion rules."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1865
|
|
msgid ""
|
|
"This function creates a mutable unicode character buffer. The returned "
|
|
"object is a ctypes array of :class:`c_wchar`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1868
|
|
msgid ""
|
|
"*init_or_size* must be an integer which specifies the size of the array, or "
|
|
"a unicode string which will be used to initialize the array items."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1871
|
|
msgid ""
|
|
"If a unicode string is specified as first argument, the buffer is made one "
|
|
"item larger than the length of the string so that the last element in the "
|
|
"array is a NUL termination character. An integer can be passed as second "
|
|
"argument which allows specifying the size of the array if the length of the "
|
|
"string should not be used."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1877
|
|
msgid ""
|
|
"If the first parameter is an 8-bit string, it is converted into a unicode "
|
|
"string according to ctypes conversion rules."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1883
|
|
msgid ""
|
|
"Windows only: This function is a hook which allows implementing in-process "
|
|
"COM servers with ctypes. It is called from the DllCanUnloadNow function "
|
|
"that the _ctypes extension dll exports."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1890
|
|
msgid ""
|
|
"Windows only: This function is a hook which allows implementing in-process "
|
|
"COM servers with ctypes. It is called from the DllGetClassObject function "
|
|
"that the ``_ctypes`` extension dll exports."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1898
|
|
msgid ""
|
|
"Try to find a library and return a pathname. *name* is the library name "
|
|
"without any prefix like ``lib``, suffix like ``.so``, ``.dylib`` or version "
|
|
"number (this is the form used for the posix linker option :option:`-l`). If "
|
|
"no library can be found, returns ``None``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1905
|
|
msgid ""
|
|
"Windows only: ``find_library(\"m\")`` or ``find_library(\"c\")`` return the "
|
|
"result of a call to ``find_msvcrt()``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1913
|
|
msgid ""
|
|
"Windows only: return the filename of the VC runtime library used by Python, "
|
|
"and by the extension modules. If the name of the library cannot be "
|
|
"determined, ``None`` is returned."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1917
|
|
msgid ""
|
|
"If you need to free memory, for example, allocated by an extension module "
|
|
"with a call to the ``free(void *)``, it is important that you use the "
|
|
"function in the same library that allocated the memory."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1926
|
|
msgid ""
|
|
"Windows only: Returns a textual description of the error code *code*. If no "
|
|
"error code is specified, the last error code is used by calling the Windows "
|
|
"api function GetLastError."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1933
|
|
msgid ""
|
|
"Windows only: Returns the last error code set by Windows in the calling "
|
|
"thread. This function calls the Windows `GetLastError()` function directly, "
|
|
"it does not return the ctypes-private copy of the error code."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1939
|
|
msgid ""
|
|
"Returns the current value of the ctypes-private copy of the system :data:"
|
|
"`errno` variable in the calling thread."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1946
|
|
msgid ""
|
|
"Windows only: returns the current value of the ctypes-private copy of the "
|
|
"system :data:`LastError` variable in the calling thread."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1953
|
|
msgid ""
|
|
"Same as the standard C memmove library function: copies *count* bytes from "
|
|
"*src* to *dst*. *dst* and *src* must be integers or ctypes instances that "
|
|
"can be converted to pointers."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1960
|
|
msgid ""
|
|
"Same as the standard C memset library function: fills the memory block at "
|
|
"address *dst* with *count* bytes of value *c*. *dst* must be an integer "
|
|
"specifying an address, or a ctypes instance."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1967
|
|
msgid ""
|
|
"This factory function creates and returns a new ctypes pointer type. Pointer "
|
|
"types are cached and reused internally, so calling this function repeatedly "
|
|
"is cheap. *type* must be a ctypes type."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1974
|
|
msgid ""
|
|
"This function creates a new pointer instance, pointing to *obj*. The "
|
|
"returned object is of the type ``POINTER(type(obj))``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1977
|
|
msgid ""
|
|
"Note: If you just want to pass a pointer to an object to a foreign function "
|
|
"call, you should use ``byref(obj)`` which is much faster."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1983
|
|
msgid ""
|
|
"This function resizes the internal memory buffer of *obj*, which must be an "
|
|
"instance of a ctypes type. It is not possible to make the buffer smaller "
|
|
"than the native size of the objects type, as given by ``sizeof(type(obj))``, "
|
|
"but it is possible to enlarge the buffer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1991
|
|
msgid ""
|
|
"This function sets the rules that ctypes objects use when converting between "
|
|
"8-bit strings and unicode strings. *encoding* must be a string specifying "
|
|
"an encoding, like ``'utf-8'`` or ``'mbcs'``, *errors* must be a string "
|
|
"specifying the error handling on encoding/decoding errors. Examples of "
|
|
"possible values are ``\"strict\"``, ``\"replace\"``, or ``\"ignore\"``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:1997
|
|
msgid ""
|
|
":func:`set_conversion_mode` returns a 2-tuple containing the previous "
|
|
"conversion rules. On windows, the initial conversion rules are ``('mbcs', "
|
|
"'ignore')``, on other systems ``('ascii', 'strict')``."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2004
|
|
msgid ""
|
|
"Set the current value of the ctypes-private copy of the system :data:`errno` "
|
|
"variable in the calling thread to *value* and return the previous value."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2012
|
|
msgid ""
|
|
"Windows only: set the current value of the ctypes-private copy of the "
|
|
"system :data:`LastError` variable in the calling thread to *value* and "
|
|
"return the previous value."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2021
|
|
msgid ""
|
|
"Returns the size in bytes of a ctypes type or instance memory buffer. Does "
|
|
"the same as the C ``sizeof`` operator."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2027
|
|
msgid ""
|
|
"This function returns the string starting at memory address *address*. If "
|
|
"size is specified, it is used as size, otherwise the string is assumed to be "
|
|
"zero-terminated."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2034
|
|
msgid ""
|
|
"Windows only: this function is probably the worst-named thing in ctypes. It "
|
|
"creates an instance of WindowsError. If *code* is not specified, "
|
|
"``GetLastError`` is called to determine the error code. If ``descr`` is not "
|
|
"specified, :func:`FormatError` is called to get a textual description of the "
|
|
"error."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2043
|
|
msgid ""
|
|
"This function returns the wide character string starting at memory address "
|
|
"*address* as unicode string. If *size* is specified, it is used as the "
|
|
"number of characters of the string, otherwise the string is assumed to be "
|
|
"zero-terminated."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2052
|
|
msgid "Data types"
|
|
msgstr "Types de données"
|
|
|
|
#: ../Doc/library/ctypes.rst:2057
|
|
msgid ""
|
|
"This non-public class is the common base class of all ctypes data types. "
|
|
"Among other things, all ctypes type instances contain a memory block that "
|
|
"hold C compatible data; the address of the memory block is returned by the :"
|
|
"func:`addressof` helper function. Another instance variable is exposed as :"
|
|
"attr:`_objects`; this contains other Python objects that need to be kept "
|
|
"alive in case the memory block contains pointers."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2064
|
|
msgid ""
|
|
"Common methods of ctypes data types, these are all class methods (to be "
|
|
"exact, they are methods of the :term:`metaclass`):"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2070
|
|
msgid ""
|
|
"This method returns a ctypes instance that shares the buffer of the *source* "
|
|
"object. The *source* object must support the writeable buffer interface. "
|
|
"The optional *offset* parameter specifies an offset into the source buffer "
|
|
"in bytes; the default is zero. If the source buffer is not large enough a :"
|
|
"exc:`ValueError` is raised."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2081
|
|
msgid ""
|
|
"This method creates a ctypes instance, copying the buffer from the *source* "
|
|
"object buffer which must be readable. The optional *offset* parameter "
|
|
"specifies an offset into the source buffer in bytes; the default is zero. "
|
|
"If the source buffer is not large enough a :exc:`ValueError` is raised."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2092
|
|
msgid ""
|
|
"This method returns a ctypes type instance using the memory specified by "
|
|
"*address* which must be an integer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2098
|
|
msgid ""
|
|
"This method adapts *obj* to a ctypes type. It is called with the actual "
|
|
"object used in a foreign function call when the type is present in the "
|
|
"foreign function's :attr:`argtypes` tuple; it must return an object that can "
|
|
"be used as a function call parameter."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2103
|
|
msgid ""
|
|
"All ctypes data types have a default implementation of this classmethod that "
|
|
"normally returns *obj* if that is an instance of the type. Some types "
|
|
"accept other objects as well."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2110
|
|
msgid ""
|
|
"This method returns a ctypes type instance exported by a shared library. "
|
|
"*name* is the name of the symbol that exports the data, *library* is the "
|
|
"loaded shared library."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2115
|
|
msgid "Common instance variables of ctypes data types:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2119
|
|
msgid ""
|
|
"Sometimes ctypes data instances do not own the memory block they contain, "
|
|
"instead they share part of the memory block of a base object. The :attr:"
|
|
"`_b_base_` read-only member is the root ctypes object that owns the memory "
|
|
"block."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2127
|
|
msgid ""
|
|
"This read-only variable is true when the ctypes data instance has allocated "
|
|
"the memory block itself, false otherwise."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2133
|
|
msgid ""
|
|
"This member is either ``None`` or a dictionary containing Python objects "
|
|
"that need to be kept alive so that the memory block contents is kept valid. "
|
|
"This object is only exposed for debugging; never modify the contents of this "
|
|
"dictionary."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2147
|
|
msgid ""
|
|
"This non-public class is the base class of all fundamental ctypes data "
|
|
"types. It is mentioned here because it contains the common attributes of the "
|
|
"fundamental ctypes data types. :class:`_SimpleCData` is a subclass of :"
|
|
"class:`_CData`, so it inherits their methods and attributes."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2152
|
|
msgid ""
|
|
"ctypes data types that are not and do not contain pointers can now be "
|
|
"pickled."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2156
|
|
msgid "Instances have a single attribute:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2160
|
|
msgid ""
|
|
"This attribute contains the actual value of the instance. For integer and "
|
|
"pointer types, it is an integer, for character types, it is a single "
|
|
"character string, for character pointer types it is a Python string or "
|
|
"unicode string."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2165
|
|
msgid ""
|
|
"When the ``value`` attribute is retrieved from a ctypes instance, usually a "
|
|
"new object is returned each time. :mod:`ctypes` does *not* implement "
|
|
"original object return, always a new object is constructed. The same is "
|
|
"true for all other ctypes object instances."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2171
|
|
msgid ""
|
|
"Fundamental data types, when returned as foreign function call results, or, "
|
|
"for example, by retrieving structure field members or array items, are "
|
|
"transparently converted to native Python types. In other words, if a "
|
|
"foreign function has a :attr:`restype` of :class:`c_char_p`, you will always "
|
|
"receive a Python string, *not* a :class:`c_char_p` instance."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2177
|
|
msgid ""
|
|
"Subclasses of fundamental data types do *not* inherit this behavior. So, if "
|
|
"a foreign functions :attr:`restype` is a subclass of :class:`c_void_p`, you "
|
|
"will receive an instance of this subclass from the function call. Of course, "
|
|
"you can get the value of the pointer by accessing the ``value`` attribute."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2182
|
|
msgid "These are the fundamental ctypes data types:"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2186
|
|
msgid ""
|
|
"Represents the C :c:type:`signed char` datatype, and interprets the value as "
|
|
"small integer. The constructor accepts an optional integer initializer; no "
|
|
"overflow checking is done."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2193
|
|
msgid ""
|
|
"Represents the C :c:type:`char` datatype, and interprets the value as a "
|
|
"single character. The constructor accepts an optional string initializer, "
|
|
"the length of the string must be exactly one character."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2200
|
|
msgid ""
|
|
"Represents the C :c:type:`char *` datatype when it points to a zero-"
|
|
"terminated string. For a general character pointer that may also point to "
|
|
"binary data, ``POINTER(c_char)`` must be used. The constructor accepts an "
|
|
"integer address, or a string."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2208
|
|
msgid ""
|
|
"Represents the C :c:type:`double` datatype. The constructor accepts an "
|
|
"optional float initializer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2214
|
|
msgid ""
|
|
"Represents the C :c:type:`long double` datatype. The constructor accepts an "
|
|
"optional float initializer. On platforms where ``sizeof(long double) == "
|
|
"sizeof(double)`` it is an alias to :class:`c_double`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2222
|
|
msgid ""
|
|
"Represents the C :c:type:`float` datatype. The constructor accepts an "
|
|
"optional float initializer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2228
|
|
msgid ""
|
|
"Represents the C :c:type:`signed int` datatype. The constructor accepts an "
|
|
"optional integer initializer; no overflow checking is done. On platforms "
|
|
"where ``sizeof(int) == sizeof(long)`` it is an alias to :class:`c_long`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2235
|
|
msgid ""
|
|
"Represents the C 8-bit :c:type:`signed int` datatype. Usually an alias for :"
|
|
"class:`c_byte`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2241
|
|
msgid ""
|
|
"Represents the C 16-bit :c:type:`signed int` datatype. Usually an alias "
|
|
"for :class:`c_short`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2247
|
|
msgid ""
|
|
"Represents the C 32-bit :c:type:`signed int` datatype. Usually an alias "
|
|
"for :class:`c_int`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2253
|
|
msgid ""
|
|
"Represents the C 64-bit :c:type:`signed int` datatype. Usually an alias "
|
|
"for :class:`c_longlong`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2259
|
|
msgid ""
|
|
"Represents the C :c:type:`signed long` datatype. The constructor accepts an "
|
|
"optional integer initializer; no overflow checking is done."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2265
|
|
msgid ""
|
|
"Represents the C :c:type:`signed long long` datatype. The constructor "
|
|
"accepts an optional integer initializer; no overflow checking is done."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2271
|
|
msgid ""
|
|
"Represents the C :c:type:`signed short` datatype. The constructor accepts "
|
|
"an optional integer initializer; no overflow checking is done."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2277
|
|
msgid "Represents the C :c:type:`size_t` datatype."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2282
|
|
msgid "Represents the C :c:type:`ssize_t` datatype."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2289
|
|
msgid ""
|
|
"Represents the C :c:type:`unsigned char` datatype, it interprets the value "
|
|
"as small integer. The constructor accepts an optional integer initializer; "
|
|
"no overflow checking is done."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2296
|
|
msgid ""
|
|
"Represents the C :c:type:`unsigned int` datatype. The constructor accepts "
|
|
"an optional integer initializer; no overflow checking is done. On platforms "
|
|
"where ``sizeof(int) == sizeof(long)`` it is an alias for :class:`c_ulong`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2303
|
|
msgid ""
|
|
"Represents the C 8-bit :c:type:`unsigned int` datatype. Usually an alias "
|
|
"for :class:`c_ubyte`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2309
|
|
msgid ""
|
|
"Represents the C 16-bit :c:type:`unsigned int` datatype. Usually an alias "
|
|
"for :class:`c_ushort`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2315
|
|
msgid ""
|
|
"Represents the C 32-bit :c:type:`unsigned int` datatype. Usually an alias "
|
|
"for :class:`c_uint`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2321
|
|
msgid ""
|
|
"Represents the C 64-bit :c:type:`unsigned int` datatype. Usually an alias "
|
|
"for :class:`c_ulonglong`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2327
|
|
msgid ""
|
|
"Represents the C :c:type:`unsigned long` datatype. The constructor accepts "
|
|
"an optional integer initializer; no overflow checking is done."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2333
|
|
msgid ""
|
|
"Represents the C :c:type:`unsigned long long` datatype. The constructor "
|
|
"accepts an optional integer initializer; no overflow checking is done."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2339
|
|
msgid ""
|
|
"Represents the C :c:type:`unsigned short` datatype. The constructor accepts "
|
|
"an optional integer initializer; no overflow checking is done."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2345
|
|
msgid ""
|
|
"Represents the C :c:type:`void *` type. The value is represented as "
|
|
"integer. The constructor accepts an optional integer initializer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2351
|
|
msgid ""
|
|
"Represents the C :c:type:`wchar_t` datatype, and interprets the value as a "
|
|
"single character unicode string. The constructor accepts an optional string "
|
|
"initializer, the length of the string must be exactly one character."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2358
|
|
msgid ""
|
|
"Represents the C :c:type:`wchar_t *` datatype, which must be a pointer to a "
|
|
"zero-terminated wide character string. The constructor accepts an integer "
|
|
"address, or a string."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2365
|
|
msgid ""
|
|
"Represent the C :c:type:`bool` datatype (more accurately, :c:type:`_Bool` "
|
|
"from C99). Its value can be ``True`` or ``False``, and the constructor "
|
|
"accepts any object that has a truth value."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2374
|
|
msgid ""
|
|
"Windows only: Represents a :c:type:`HRESULT` value, which contains success "
|
|
"or error information for a function or method call."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2380
|
|
msgid ""
|
|
"Represents the C :c:type:`PyObject *` datatype. Calling this without an "
|
|
"argument creates a ``NULL`` :c:type:`PyObject *` pointer."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2383
|
|
msgid ""
|
|
"The :mod:`ctypes.wintypes` module provides quite some other Windows specific "
|
|
"data types, for example :c:type:`HWND`, :c:type:`WPARAM`, or :c:type:"
|
|
"`DWORD`. Some useful structures like :c:type:`MSG` or :c:type:`RECT` are "
|
|
"also defined."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2391
|
|
msgid "Structured data types"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2396
|
|
msgid "Abstract base class for unions in native byte order."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2401
|
|
msgid "Abstract base class for structures in *big endian* byte order."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2406
|
|
msgid "Abstract base class for structures in *little endian* byte order."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2408
|
|
msgid ""
|
|
"Structures with non-native byte order cannot contain pointer type fields, or "
|
|
"any other data types containing pointer type fields."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2414
|
|
msgid "Abstract base class for structures in *native* byte order."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2416
|
|
msgid ""
|
|
"Concrete structure and union types must be created by subclassing one of "
|
|
"these types, and at least define a :attr:`_fields_` class variable. :mod:"
|
|
"`ctypes` will create :term:`descriptor`\\s which allow reading and writing "
|
|
"the fields by direct attribute accesses. These are the"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2424
|
|
msgid ""
|
|
"A sequence defining the structure fields. The items must be 2-tuples or 3-"
|
|
"tuples. The first item is the name of the field, the second item specifies "
|
|
"the type of the field; it can be any ctypes data type."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2428
|
|
msgid ""
|
|
"For integer type fields like :class:`c_int`, a third optional item can be "
|
|
"given. It must be a small positive integer defining the bit width of the "
|
|
"field."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2432
|
|
msgid ""
|
|
"Field names must be unique within one structure or union. This is not "
|
|
"checked, only one field can be accessed when names are repeated."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2435
|
|
msgid ""
|
|
"It is possible to define the :attr:`_fields_` class variable *after* the "
|
|
"class statement that defines the Structure subclass, this allows creating "
|
|
"data types that directly or indirectly reference themselves::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2445
|
|
msgid ""
|
|
"The :attr:`_fields_` class variable must, however, be defined before the "
|
|
"type is first used (an instance is created, ``sizeof()`` is called on it, "
|
|
"and so on). Later assignments to the :attr:`_fields_` class variable will "
|
|
"raise an AttributeError."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2450
|
|
msgid ""
|
|
"It is possible to defined sub-subclasses of structure types, they inherit "
|
|
"the fields of the base class plus the :attr:`_fields_` defined in the sub-"
|
|
"subclass, if any."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2457
|
|
msgid ""
|
|
"An optional small integer that allows overriding the alignment of structure "
|
|
"fields in the instance. :attr:`_pack_` must already be defined when :attr:"
|
|
"`_fields_` is assigned, otherwise it will have no effect."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2464
|
|
msgid ""
|
|
"An optional sequence that lists the names of unnamed (anonymous) fields. :"
|
|
"attr:`_anonymous_` must be already defined when :attr:`_fields_` is "
|
|
"assigned, otherwise it will have no effect."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2468
|
|
msgid ""
|
|
"The fields listed in this variable must be structure or union type fields. :"
|
|
"mod:`ctypes` will create descriptors in the structure type that allow "
|
|
"accessing the nested fields directly, without the need to create the "
|
|
"structure or union field."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2473
|
|
msgid "Here is an example type (Windows)::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2486
|
|
msgid ""
|
|
"The ``TYPEDESC`` structure describes a COM data type, the ``vt`` field "
|
|
"specifies which one of the union fields is valid. Since the ``u`` field is "
|
|
"defined as anonymous field, it is now possible to access the members "
|
|
"directly off the TYPEDESC instance. ``td.lptdesc`` and ``td.u.lptdesc`` are "
|
|
"equivalent, but the former is faster since it does not need to create a "
|
|
"temporary union instance::"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2498
|
|
msgid ""
|
|
"It is possible to defined sub-subclasses of structures, they inherit the "
|
|
"fields of the base class. If the subclass definition has a separate :attr:"
|
|
"`_fields_` variable, the fields specified in this are appended to the fields "
|
|
"of the base class."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2503
|
|
msgid ""
|
|
"Structure and union constructors accept both positional and keyword "
|
|
"arguments. Positional arguments are used to initialize member fields in the "
|
|
"same order as they are appear in :attr:`_fields_`. Keyword arguments in the "
|
|
"constructor are interpreted as attribute assignments, so they will "
|
|
"initialize :attr:`_fields_` with the same name, or create new attributes for "
|
|
"names not present in :attr:`_fields_`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2514
|
|
msgid "Arrays and pointers"
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2518
|
|
msgid "Abstract base class for arrays."
|
|
msgstr "Classe de base abstraite pour les *arrays*."
|
|
|
|
#: ../Doc/library/ctypes.rst:2520
|
|
msgid ""
|
|
"The recommended way to create concrete array types is by multiplying any :"
|
|
"mod:`ctypes` data type with a positive integer. Alternatively, you can "
|
|
"subclass this type and define :attr:`_length_` and :attr:`_type_` class "
|
|
"variables. Array elements can be read and written using standard subscript "
|
|
"and slice accesses; for slice reads, the resulting object is *not* itself "
|
|
"an :class:`Array`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2530
|
|
msgid ""
|
|
"A positive integer specifying the number of elements in the array. Out-of-"
|
|
"range subscripts result in an :exc:`IndexError`. Will be returned by :func:"
|
|
"`len`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2537
|
|
msgid "Specifies the type of each element in the array."
|
|
msgstr "Spécifie le type de chaque élément de l'*array*."
|
|
|
|
#: ../Doc/library/ctypes.rst:2540
|
|
msgid ""
|
|
"Array subclass constructors accept positional arguments, used to initialize "
|
|
"the elements in order."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2546
|
|
msgid "Private, abstract base class for pointers."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2548
|
|
msgid ""
|
|
"Concrete pointer types are created by calling :func:`POINTER` with the type "
|
|
"that will be pointed to; this is done automatically by :func:`pointer`."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2552
|
|
msgid ""
|
|
"If a pointer points to an array, its elements can be read and written using "
|
|
"standard subscript and slice accesses. Pointer objects have no size, so :"
|
|
"func:`len` will raise :exc:`TypeError`. Negative subscripts will read from "
|
|
"the memory *before* the pointer (as in C), and out-of-range subscripts will "
|
|
"probably crash with an access violation (if you're lucky)."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2562
|
|
msgid "Specifies the type pointed to."
|
|
msgstr ""
|
|
|
|
#: ../Doc/library/ctypes.rst:2566
|
|
msgid ""
|
|
"Returns the object to which to pointer points. Assigning to this attribute "
|
|
"changes the pointer to point to the assigned object."
|
|
msgstr ""
|