diff options
Diffstat (limited to 'Doc/library/zlib.rst')
| -rw-r--r-- | Doc/library/zlib.rst | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/Doc/library/zlib.rst b/Doc/library/zlib.rst index 1de7baee54..3d742ab35b 100644 --- a/Doc/library/zlib.rst +++ b/Doc/library/zlib.rst @@ -47,14 +47,19 @@ The available exception and functions in this module are: platforms, use ``adler32(data) & 0xffffffff``. -.. function:: compress(data[, level]) +.. function:: compress(data, level=-1) Compresses the bytes in *data*, returning a bytes object containing compressed data. - *level* is an integer from ``0`` to ``9`` controlling the level of compression; + *level* is an integer from ``0`` to ``9`` or ``-1`` controlling the level of compression; ``1`` is fastest and produces the least compression, ``9`` is slowest and - produces the most. ``0`` is no compression. The default value is ``6``. + produces the most. ``0`` is no compression. The default value is ``-1`` + (Z_DEFAULT_COMPRESSION). Z_DEFAULT_COMPRESSION represents a default + compromise between speed and compression (currently equivalent to level 6). Raises the :exc:`error` exception if any error occurs. + .. versionchanged:: 3.6 + *level* can now be used as a keyword parameter. + .. function:: compressobj(level=-1, method=DEFLATED, wbits=15, memLevel=8, strategy=Z_DEFAULT_STRATEGY[, zdict]) @@ -124,7 +129,7 @@ The available exception and functions in this module are: platforms, use ``crc32(data) & 0xffffffff``. -.. function:: decompress(data[, wbits[, bufsize]]) +.. function:: decompress(data, wbits=MAX_WBITS, bufsize=DEF_BUF_SIZE) Decompresses the bytes in *data*, returning a bytes object containing the uncompressed data. The *wbits* parameter depends on @@ -159,14 +164,16 @@ The available exception and functions in this module are: When decompressing a stream, the window size must not be smaller than the size originally used to compress the stream; using a too-small value may result in an :exc:`error` exception. The default *wbits* value - is 15, which corresponds to the largest window size and requires a zlib - header and trailer to be included. + corresponds to the largest window size and requires a zlib header and + trailer to be included. *bufsize* is the initial size of the buffer used to hold decompressed data. If more space is required, the buffer size will be increased as needed, so you don't have to get this value exactly right; tuning it will only save a few calls - to :c:func:`malloc`. The default size is 16384. + to :c:func:`malloc`. + .. versionchanged:: 3.6 + *wbits* and *bufsize* can be used as keyword arguments. .. function:: decompressobj(wbits=15[, zdict]) @@ -252,7 +259,7 @@ Decompression objects support the following methods and attributes: .. versionadded:: 3.3 -.. method:: Decompress.decompress(data[, max_length]) +.. method:: Decompress.decompress(data, max_length=0) Decompress *data*, returning a bytes object containing the uncompressed data corresponding to at least part of the data in *string*. This data should be @@ -264,9 +271,11 @@ Decompression objects support the following methods and attributes: no longer than *max_length*. This may mean that not all of the compressed input can be processed; and unconsumed data will be stored in the attribute :attr:`unconsumed_tail`. This bytestring must be passed to a subsequent call to - :meth:`decompress` if decompression is to continue. If *max_length* is not - supplied then the whole input is decompressed, and :attr:`unconsumed_tail` is - empty. + :meth:`decompress` if decompression is to continue. If *max_length* is zero + then the whole input is decompressed, and :attr:`unconsumed_tail` is empty. + + .. versionchanged:: 3.6 + *max_length* can be used as a keyword argument. .. method:: Decompress.flush([length]) |