deflate_init

(PHP 7, PHP 8)

deflate_initInitialize an incremental deflate context

Description

deflate_init(int $encoding, array $options = []): DeflateContext|false

Initializes an incremental deflate context using the specified encoding.

Note that the window option here only sets the window size of the algorithm, differently from the zlib filters where the same parameter also sets the encoding to use; the encoding must be set with the encoding parameter.

Limitation: there is currently no way to set the header information on a GZIP compressed stream, which are set as follows: GZIP signature (\x1f\x8B); compression method (\x08 == DEFLATE); 6 zero bytes; the operating system set to the current system (\x00 = Windows, \x03 = Unix, etc.)

Parameters

encoding

One of the ZLIB_ENCODING_* constants.

options

An associative array which may contain the following elements:

level

The compression level in range -1..9; defaults to -1.

memory

The compression memory level in range 1..9; defaults to 8.

window

The zlib window size (logarithmic) in range 8..15; defaults to 15. zlib changes a window size of 8 to 9, and as of zlib 1.2.8 fails with a warning, if a window size of 8 is requested for ZLIB_ENCODING_RAW or ZLIB_ENCODING_GZIP.

strategy

One of ZLIB_FILTERED, ZLIB_HUFFMAN_ONLY, ZLIB_RLE, ZLIB_FIXED or ZLIB_DEFAULT_STRATEGY (the default).

dictionary

A string or an array of strings of the preset dictionary (default: no preset dictionary).

Return Values

Returns a deflate context resource (zlib.deflate) on success, or false on failure.

Errors/Exceptions

If an invalid option is passed to options or the context couldn't be created, an error of level E_WARNING is generated.

Changelog

Version Description
8.0.0 On success, this function returns a DeflateContext instance now; previously, a resource was returned.

See Also

Here you can write a comment


Please enter at least 10 characters.
Loading... Please wait.
* Pflichtangabe
There are no comments available yet.

PHP cURL Tutorial: Using cURL to Make HTTP Requests

cURL is a powerful PHP extension that allows you to communicate with different servers using various protocols, including HTTP, HTTPS, FTP, and more. ...

TheMax

Autor : TheMax
Category: PHP-Tutorials

Midjourney Tutorial - Instructions for beginners

There is an informative video about Midjourney, the tool for creating digital images using artificial intelligence, entitled "Midjourney tutorial in German - instructions for beginners" ...

Mike94

Autor : Mike94
Category: KI Tutorials

Basics of views in MySQL

Views in a MySQL database offer the option of creating a virtual table based on the result of an SQL query. This virtual table can be queried like a normal table without changing the underlying data. ...

admin

Autor : admin
Category: mySQL-Tutorials

Publish a tutorial

Share your knowledge with other developers worldwide

Share your knowledge with other developers worldwide

You are a professional in your field and want to share your knowledge, then sign up now and share it with our PHP community

learn more

Publish a tutorial