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# SOME DESCRIPTIVE TITLE.
# Copyright (C) 2001-2024, Python Software Foundation
# This file is distributed under the same license as the Python package.
# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
"Project-Id-Version: Python 3.12\n"
"Report-Msgid-Bugs-To: \n"
"POT-Creation-Date: 2025-12-04 09:48+0200\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
"Language: \n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
#: c-api/buffer.rst:11
msgid "Buffer Protocol"
#: c-api/buffer.rst:18
"Certain objects available in Python wrap access to an underlying memory "
"array or *buffer*.  Such objects include the built-in :class:`bytes` and :"
"class:`bytearray`, and some extension types like :class:`array.array`. Third-"
"party libraries may define their own types for special purposes, such as "
"image processing or numeric analysis."
#: c-api/buffer.rst:24
"While each of these types have their own semantics, they share the common "
"characteristic of being backed by a possibly large memory buffer.  It is "
"then desirable, in some situations, to access that buffer directly and "
"without intermediate copying."
#: c-api/buffer.rst:29
"Python provides such a facility at the C and Python level in the form of "
"the :ref:`buffer protocol <bufferobjects>`.  This protocol has two sides:"
#: c-api/buffer.rst:34
"on the producer side, a type can export a \"buffer interface\" which allows "
"objects of that type to expose information about their underlying buffer. "
"This interface is described in the section :ref:`buffer-structs`; for Python "
"see :ref:`python-buffer-protocol`."
#: c-api/buffer.rst:39
"on the consumer side, several means are available to obtain a pointer to the "
"raw underlying data of an object (for example a method parameter). For "
"Python see :class:`memoryview`."
#: c-api/buffer.rst:43
"Simple objects such as :class:`bytes` and :class:`bytearray` expose their "
"underlying buffer in byte-oriented form.  Other forms are possible; for "
"example, the elements exposed by an :class:`array.array` can be multi-byte "
#: c-api/buffer.rst:47
"An example consumer of the buffer interface is the :meth:`~io.BufferedIOBase."
"write` method of file objects: any object that can export a series of bytes "
"through the buffer interface can be written to a file.  While :meth:`!write` "
"only needs read-only access to the internal contents of the object passed to "
"it, other methods such as :meth:`~io.BufferedIOBase.readinto` need write "
"access to the contents of their argument.  The buffer interface allows "
"objects to selectively allow or reject exporting of read-write and read-only "
#: c-api/buffer.rst:55
"There are two ways for a consumer of the buffer interface to acquire a "
"buffer over a target object:"
#: c-api/buffer.rst:58
msgid "call :c:func:`PyObject_GetBuffer` with the right parameters;"
#: c-api/buffer.rst:60
"call :c:func:`PyArg_ParseTuple` (or one of its siblings) with one of the "
"``y*``, ``w*`` or ``s*`` :ref:`format codes <arg-parsing>`."
#: c-api/buffer.rst:63
"In both cases, :c:func:`PyBuffer_Release` must be called when the buffer "
"isn't needed anymore.  Failure to do so could lead to various issues such as "
"resource leaks."
#: c-api/buffer.rst:69
"The buffer protocol is now accessible in Python, see :ref:`python-buffer-"
"protocol` and :class:`memoryview`."
#: c-api/buffer.rst:75
msgid "Buffer structure"
#: c-api/buffer.rst:77
"Buffer structures (or simply \"buffers\") are useful as a way to expose the "
"binary data from another object to the Python programmer.  They can also be "
"used as a zero-copy slicing mechanism.  Using their ability to reference a "
"block of memory, it is possible to expose any data to the Python programmer "
"quite easily.  The memory could be a large, constant array in a C extension, "
"it could be a raw block of memory for manipulation before passing to an "
"operating system library, or it could be used to pass around structured data "
"in its native, in-memory format."
#: c-api/buffer.rst:86
"Contrary to most data types exposed by the Python interpreter, buffers are "
"not :c:type:`PyObject` pointers but rather simple C structures.  This allows "
"them to be created and copied very simply.  When a generic wrapper around a "
"buffer is needed, a :ref:`memoryview <memoryview-objects>` object can be "
#: c-api/buffer.rst:92
"For short instructions how to write an exporting object, see :ref:`Buffer "
"Object Structures <buffer-structs>`. For obtaining a buffer, see :c:func:"
"`PyObject_GetBuffer`."
#: c-api/buffer.rst:100
"A pointer to the start of the logical structure described by the buffer "
"fields. This can be any location within the underlying physical memory block "
"of the exporter. For example, with negative :c:member:`~Py_buffer.strides` "
"the value may point to the end of the memory block."
#: c-api/buffer.rst:105
"For :term:`contiguous` arrays, the value points to the beginning of the "
"memory block."
#: c-api/buffer.rst:110
"A new reference to the exporting object. The reference is owned by the "
"consumer and automatically released (i.e. reference count decremented) and "
"set to ``NULL`` by :c:func:`PyBuffer_Release`. The field is the equivalent "
"of the return value of any standard C-API function."
#: c-api/buffer.rst:117
"As a special case, for *temporary* buffers that are wrapped by :c:func:"
"`PyMemoryView_FromBuffer` or :c:func:`PyBuffer_FillInfo` this field is "
"``NULL``. In general, exporting objects MUST NOT use this scheme."
#: c-api/buffer.rst:124
"``product(shape) * itemsize``. For contiguous arrays, this is the length of "
"the underlying memory block. For non-contiguous arrays, it is the length "
"that the logical structure would have if it were copied to a contiguous "
"representation."
#: c-api/buffer.rst:129
"Accessing ``((char *)buf)[0] up to ((char *)buf)[len-1]`` is only valid if "
"the buffer has been obtained by a request that guarantees contiguity. In "
"most cases such a request will be :c:macro:`PyBUF_SIMPLE` or :c:macro:"
"`PyBUF_WRITABLE`."
#: c-api/buffer.rst:135
"An indicator of whether the buffer is read-only. This field is controlled by "
"the :c:macro:`PyBUF_WRITABLE` flag."
#: c-api/buffer.rst:140
"Item size in bytes of a single element. Same as the value of :func:`struct."
"calcsize` called on non-``NULL`` :c:member:`~Py_buffer.format` values."
#: c-api/buffer.rst:143
"Important exception: If a consumer requests a buffer without the :c:macro:"
"`PyBUF_FORMAT` flag, :c:member:`~Py_buffer.format` will be set to  "
"``NULL``,  but :c:member:`~Py_buffer.itemsize` still has the value for the "
"original format."
#: c-api/buffer.rst:148
"If :c:member:`~Py_buffer.shape` is present, the equality ``product(shape) * "
"itemsize == len`` still holds and the consumer can use :c:member:`~Py_buffer."
"itemsize` to navigate the buffer."
#: c-api/buffer.rst:152
"If :c:member:`~Py_buffer.shape` is ``NULL`` as a result of a :c:macro:"
"`PyBUF_SIMPLE` or a :c:macro:`PyBUF_WRITABLE` request, the consumer must "
"disregard :c:member:`~Py_buffer.itemsize` and assume ``itemsize == 1``."
#: c-api/buffer.rst:158
"A *NULL* terminated string in :mod:`struct` module style syntax describing "
"the contents of a single item. If this is ``NULL``, ``\"B\"`` (unsigned "
"bytes) is assumed."
#: c-api/buffer.rst:162
msgid "This field is controlled by the :c:macro:`PyBUF_FORMAT` flag."
#: c-api/buffer.rst:166
"The number of dimensions the memory represents as an n-dimensional array. If "
"it is ``0``, :c:member:`~Py_buffer.buf` points to a single item representing "
"a scalar. In this case, :c:member:`~Py_buffer.shape`, :c:member:`~Py_buffer."
"strides` and :c:member:`~Py_buffer.suboffsets` MUST be ``NULL``. The maximum "
"number of dimensions is given by :c:macro:`PyBUF_MAX_NDIM`."
#: c-api/buffer.rst:174
"An array of :c:type:`Py_ssize_t` of length :c:member:`~Py_buffer.ndim` "
"indicating the shape of the memory as an n-dimensional array. Note that "
"``shape[0] * ... * shape[ndim-1] * itemsize`` MUST be equal to :c:member:"
"`~Py_buffer.len`."
#: c-api/buffer.rst:179
"Shape values are restricted to ``shape[n] >= 0``. The case ``shape[n] == 0`` "
"requires special attention. See `complex arrays`_ for further information."
#: c-api/buffer.rst:183
msgid "The shape array is read-only for the consumer."
#: c-api/buffer.rst:187
"An array of :c:type:`Py_ssize_t` of length :c:member:`~Py_buffer.ndim` "
"giving the number of bytes to skip to get to a new element in each dimension."
#: c-api/buffer.rst:191
"Stride values can be any integer. For regular arrays, strides are usually "
"positive, but a consumer MUST be able to handle the case ``strides[n] <= "
"0``. See `complex arrays`_ for further information."
#: c-api/buffer.rst:195
msgid "The strides array is read-only for the consumer."
#: c-api/buffer.rst:199
"An array of :c:type:`Py_ssize_t` of length :c:member:`~Py_buffer.ndim`. If "
"``suboffsets[n] >= 0``, the values stored along the nth dimension are "
"pointers and the suboffset value dictates how many bytes to add to each "
"pointer after de-referencing. A suboffset value that is negative indicates "
"that no de-referencing should occur (striding in a contiguous memory block)."
#: c-api/buffer.rst:206
"If all suboffsets are negative (i.e. no de-referencing is needed), then this "
"field must be ``NULL`` (the default value)."
#: c-api/buffer.rst:209
"This type of array representation is used by the Python Imaging Library "
"(PIL). See `complex arrays`_ for further information how to access elements "
"of such an array."
#: c-api/buffer.rst:213
msgid "The suboffsets array is read-only for the consumer."
#: c-api/buffer.rst:217
"This is for use internally by the exporting object. For example, this might "
"be re-cast as an integer by the exporter and used to store flags about "
"whether or not the shape, strides, and suboffsets arrays must be freed when "
"the buffer is released. The consumer MUST NOT alter this value."
#: c-api/buffer.rst:224
msgid "Constants:"
#: c-api/buffer.rst:228
"The maximum number of dimensions the memory represents. Exporters MUST "
"respect this limit, consumers of multi-dimensional buffers SHOULD be able to "
"handle up to :c:macro:`!PyBUF_MAX_NDIM` dimensions. Currently set to 64."
#: c-api/buffer.rst:237
msgid "Buffer request types"
#: c-api/buffer.rst:239
"Buffers are usually obtained by sending a buffer request to an exporting "
"object via :c:func:`PyObject_GetBuffer`. Since the complexity of the logical "
"structure of the memory can vary drastically, the consumer uses the *flags* "
"argument to specify the exact buffer type it can handle."
#: c-api/buffer.rst:244
"All :c:type:`Py_buffer` fields are unambiguously defined by the request type."
#: c-api/buffer.rst:248
msgid "request-independent fields"
#: c-api/buffer.rst:249
"The following fields are not influenced by *flags* and must always be filled "
"in with the correct values: :c:member:`~Py_buffer.obj`, :c:member:"
"`~Py_buffer.buf`, :c:member:`~Py_buffer.len`, :c:member:`~Py_buffer."
"itemsize`, :c:member:`~Py_buffer.ndim`."
#: c-api/buffer.rst:254
msgid "readonly, format"
#: c-api/buffer.rst:258
"Controls the :c:member:`~Py_buffer.readonly` field. If set, the exporter "
"MUST provide a writable buffer or else report failure. Otherwise, the "
"exporter MAY provide either a read-only or writable buffer, but the choice "
"MUST be consistent for all consumers. For example, :c:expr:`PyBUF_SIMPLE | "
"PyBUF_WRITABLE` can be used to request a simple writable buffer."
#: c-api/buffer.rst:266
msgid "This is a :term:`soft deprecated` alias to :c:macro:`PyBUF_WRITABLE`."
#: c-api/buffer.rst:270
"Controls the :c:member:`~Py_buffer.format` field. If set, this field MUST be "
"filled in correctly. Otherwise, this field MUST be ``NULL``."
#: c-api/buffer.rst:274
":c:macro:`PyBUF_WRITABLE` can be \\|'d to any of the flags in the next "
"section. Since :c:macro:`PyBUF_SIMPLE` is defined as 0, :c:macro:"
"`PyBUF_WRITABLE` can be used as a stand-alone flag to request a simple "
"writable buffer."
#: c-api/buffer.rst:278
":c:macro:`PyBUF_FORMAT` must be \\|'d to any of the flags except :c:macro:"
"`PyBUF_SIMPLE`, because the latter already implies format ``B`` (unsigned "
"bytes). :c:macro:`!PyBUF_FORMAT` cannot be used on its own."
#: c-api/buffer.rst:284
msgid "shape, strides, suboffsets"
#: c-api/buffer.rst:286
"The flags that control the logical structure of the memory are listed in "
"decreasing order of complexity. Note that each flag contains all bits of the "
"flags below it."
#: c-api/buffer.rst:317 c-api/buffer.rst:342
msgid "Request"
#: c-api/buffer.rst:317 c-api/buffer.rst:342
msgid "shape"
#: c-api/buffer.rst:317 c-api/buffer.rst:342
msgid "strides"
#: c-api/buffer.rst:317 c-api/buffer.rst:342
msgid "suboffsets"
#: c-api/buffer.rst:297 c-api/buffer.rst:319 c-api/buffer.rst:323
#: c-api/buffer.rst:344 c-api/buffer.rst:348 c-api/buffer.rst:352
#: c-api/buffer.rst:356 c-api/buffer.rst:358
msgid "yes"
#: c-api/buffer.rst:344 c-api/buffer.rst:346
msgid "if needed"
#: c-api/buffer.rst:299 c-api/buffer.rst:319 c-api/buffer.rst:323
#: c-api/buffer.rst:348 c-api/buffer.rst:352 c-api/buffer.rst:356
#: c-api/buffer.rst:358
msgid "NULL"
#: c-api/buffer.rst:308
msgid "contiguity requests"
#: c-api/buffer.rst:310
"C or Fortran :term:`contiguity <contiguous>` can be explicitly requested, "
"with and without stride information. Without stride information, the buffer "
"must be C-contiguous."
#: c-api/buffer.rst:342
msgid "contig"
#: c-api/buffer.rst:325 c-api/buffer.rst:358
#: c-api/buffer.rst:321
#: c-api/buffer.rst:323
msgid "C or F"
#: c-api/buffer.rst:325
msgid ":c:macro:`PyBUF_ND`"
#: c-api/buffer.rst:330
msgid "compound requests"
#: c-api/buffer.rst:332
"All possible requests are fully defined by some combination of the flags in "
"the previous section. For convenience, the buffer protocol provides "
"frequently used combinations as single flags."
#: c-api/buffer.rst:336
"In the following table *U* stands for undefined contiguity. The consumer "
"would have to call :c:func:`PyBuffer_IsContiguous` to determine contiguity."
#: c-api/buffer.rst:342
msgid "readonly"
#: c-api/buffer.rst:342
msgid "format"
#: c-api/buffer.rst:346 c-api/buffer.rst:350 c-api/buffer.rst:354
#: c-api/buffer.rst:348 c-api/buffer.rst:356
#: c-api/buffer.rst:350 c-api/buffer.rst:358
msgid "1 or 0"
#: c-api/buffer.rst:363
msgid "Complex arrays"
#: c-api/buffer.rst:366
msgid "NumPy-style: shape and strides"
#: c-api/buffer.rst:368
"The logical structure of NumPy-style arrays is defined by :c:member:"
"`~Py_buffer.itemsize`, :c:member:`~Py_buffer.ndim`, :c:member:`~Py_buffer."
"shape` and :c:member:`~Py_buffer.strides`."
#: c-api/buffer.rst:371
"If ``ndim == 0``, the memory location pointed to by :c:member:`~Py_buffer."
"buf` is interpreted as a scalar of size :c:member:`~Py_buffer.itemsize`. In "
"that case, both :c:member:`~Py_buffer.shape` and :c:member:`~Py_buffer."
"strides` are ``NULL``."
#: c-api/buffer.rst:375
"If :c:member:`~Py_buffer.strides` is ``NULL``, the array is interpreted as a "
"standard n-dimensional C-array. Otherwise, the consumer must access an n-"
"dimensional array as follows:"
#: c-api/buffer.rst:379
"ptr = (char *)buf + indices[0] * strides[0] + ... + indices[n-1] * "
"strides[n-1];\n"
"item = *((typeof(item) *)ptr);"
#: c-api/buffer.rst:385
"As noted above, :c:member:`~Py_buffer.buf` can point to any location within "
"the actual memory block. An exporter can check the validity of a buffer with "
"this function:"
#: c-api/buffer.rst:389
"def verify_structure(memlen, itemsize, ndim, shape, strides, offset):\n"
"    \"\"\"Verify that the parameters represent a valid array within\n"
"       the bounds of the allocated memory:\n"
"           char *mem: start of the physical memory block\n"
"           memlen: length of the physical memory block\n"
"           offset: (char *)buf - mem\n"
"    \"\"\"\n"
"    if offset % itemsize:\n"
"        return False\n"
"    if offset < 0 or offset+itemsize > memlen:\n"
"        return False\n"
"    if any(v % itemsize for v in strides):\n"
"        return False\n"
"    if ndim <= 0:\n"
"        return ndim == 0 and not shape and not strides\n"
"    if 0 in shape:\n"
"        return True\n"
"    imin = sum(strides[j]*(shape[j]-1) for j in range(ndim)\n"
"               if strides[j] <= 0)\n"
"    imax = sum(strides[j]*(shape[j]-1) for j in range(ndim)\n"
"               if strides[j] > 0)\n"
"    return 0 <= offset+imin and offset+imax+itemsize <= memlen"
#: c-api/buffer.rst:419
msgid "PIL-style: shape, strides and suboffsets"
#: c-api/buffer.rst:421
"In addition to the regular items, PIL-style arrays can contain pointers that "
"must be followed in order to get to the next element in a dimension. For "
"example, the regular three-dimensional C-array ``char v[2][2][3]`` can also "
"be viewed as an array of 2 pointers to 2 two-dimensional arrays: ``char "
"(*v[2])[2][3]``. In suboffsets representation, those two pointers can be "
"embedded at the start of :c:member:`~Py_buffer.buf`, pointing to two ``char "
"x[2][3]`` arrays that can be located anywhere in memory."
#: c-api/buffer.rst:430
"Here is a function that returns a pointer to the element in an N-D array "
"pointed to by an N-dimensional index when there are both non-``NULL`` "
"strides and suboffsets::"
#: c-api/buffer.rst:434
"void *get_item_pointer(int ndim, void *buf, Py_ssize_t *strides,\n"
"                       Py_ssize_t *suboffsets, Py_ssize_t *indices) {\n"
"    char *pointer = (char*)buf;\n"
"    int i;\n"
"    for (i = 0; i < ndim; i++) {\n"
"        pointer += strides[i] * indices[i];\n"
"        if (suboffsets[i] >=0 ) {\n"
"            pointer = *((char**)pointer) + suboffsets[i];\n"
"        }\n"
"    return (void*)pointer;\n"
#: c-api/buffer.rst:449
msgid "Buffer-related functions"
#: c-api/buffer.rst:453
"Return ``1`` if *obj* supports the buffer interface otherwise ``0``.  When "
"``1`` is returned, it doesn't guarantee that :c:func:`PyObject_GetBuffer` "
"will succeed.  This function always succeeds."
#: c-api/buffer.rst:460
"Send a request to *exporter* to fill in *view* as specified by  *flags*. If "
"the exporter cannot provide a buffer of the exact type, it MUST raise :exc:"
"`BufferError`, set ``view->obj`` to ``NULL`` and return ``-1``."
#: c-api/buffer.rst:465
"On success, fill in *view*, set ``view->obj`` to a new reference to "
"*exporter* and return 0. In the case of chained buffer providers that "
"redirect requests to a single object, ``view->obj`` MAY refer to this object "
"instead of *exporter* (See :ref:`Buffer Object Structures <buffer-structs>`)."
#: c-api/buffer.rst:470
"Successful calls to :c:func:`PyObject_GetBuffer` must be paired with calls "
"to :c:func:`PyBuffer_Release`, similar to :c:func:`malloc` and :c:func:"
"`free`. Thus, after the consumer is done with the buffer, :c:func:"
"`PyBuffer_Release` must be called exactly once."
#: c-api/buffer.rst:478
"Release the buffer *view* and release the :term:`strong reference` (i.e. "
"decrement the reference count) to the view's supporting object, ``view-"
">obj``. This function MUST be called when the buffer is no longer being "
"used, otherwise reference leaks may occur."
#: c-api/buffer.rst:483
"It is an error to call this function on a buffer that was not obtained via :"
"c:func:`PyObject_GetBuffer`."
#: c-api/buffer.rst:489
"Return the implied :c:member:`~Py_buffer.itemsize` from :c:member:"
"`~Py_buffer.format`. On error, raise an exception and return -1."
#: c-api/buffer.rst:497
"Return ``1`` if the memory defined by the *view* is C-style (*order* is "
"``'C'``) or Fortran-style (*order* is ``'F'``) :term:`contiguous` or either "
"one (*order* is ``'A'``).  Return ``0`` otherwise.  This function always "
"succeeds."
#: c-api/buffer.rst:504
"Get the memory area pointed to by the *indices* inside the given *view*. "
"*indices* must point to an array of ``view->ndim`` indices."
#: c-api/buffer.rst:510
"Copy contiguous *len* bytes from *buf* to *view*. *fort* can be ``'C'`` or "
"``'F'`` (for C-style or Fortran-style ordering). ``0`` is returned on "
"success, ``-1`` on error."
#: c-api/buffer.rst:517
"Copy *len* bytes from *src* to its contiguous representation in *buf*. "
"*order* can be ``'C'`` or ``'F'`` or ``'A'`` (for C-style or Fortran-style "
"ordering or either one). ``0`` is returned on success, ``-1`` on error."
#: c-api/buffer.rst:521
msgid "This function fails if *len* != *src->len*."
#: c-api/buffer.rst:526
"Copy data from *src* to *dest* buffer. Can convert between C-style and or "
"Fortran-style buffers."
#: c-api/buffer.rst:529
msgid "``0`` is returned on success, ``-1`` on error."
#: c-api/buffer.rst:533
"Fill the *strides* array with byte-strides of a :term:`contiguous` (C-style "
"if *order* is ``'C'`` or Fortran-style if *order* is ``'F'``) array of the "
"given shape with the given number of bytes per element."
#: c-api/buffer.rst:540
"Handle buffer requests for an exporter that wants to expose *buf* of size "
"*len* with writability set according to *readonly*. *buf* is interpreted as "
"a sequence of unsigned bytes."
#: c-api/buffer.rst:544
"The *flags* argument indicates the request type. This function always fills "
"in *view* as specified by flags, unless *buf* has been designated as read-"
"only and :c:macro:`PyBUF_WRITABLE` is set in *flags*."
#: c-api/buffer.rst:548
"On success, set ``view->obj`` to a new reference to *exporter* and return 0. "
"Otherwise, raise :exc:`BufferError`, set ``view->obj`` to ``NULL`` and "
"return ``-1``;"
#: c-api/buffer.rst:552
"If this function is used as part of a :ref:`getbufferproc <buffer-structs>`, "
"*exporter* MUST be set to the exporting object and *flags* must be passed "
"unmodified. Otherwise, *exporter* MUST be ``NULL``."
#: c-api/buffer.rst:3
msgid "buffer protocol"
#: c-api/buffer.rst:3
msgid "buffer interface"
#: c-api/buffer.rst:3
msgid "(see buffer protocol)"
#: c-api/buffer.rst:3
msgid "buffer object"
#: c-api/buffer.rst:32
msgid "PyBufferProcs (C type)"
#: c-api/buffer.rst:305
msgid "contiguous"
#: c-api/buffer.rst:305
msgid "C-contiguous"
#: c-api/buffer.rst:305
msgid "Fortran contiguous"
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