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# gzencode

(PHP 4 >= 4.0.4)

gzencode -- Create a gzip compressed string

## Description

string gzencode ( string data [, int level [, int encoding_mode]])

This function returns a compressed version of the input `data` compatible with the output of the gzip program, or `FALSE` if an error is encountered. The optional parameter `level` can be given as 0 for no compression up to 9 for maximum compression, if not given the default compression level will be the default compression level of the zlib library.

You can also give `FORCE_GZIP` (the default) or `FORCE_DEFLATE` as optional third paramter `encoding_mode`. If you use `FORCE_DEFLATE`, you get a standard zlib deflated string (inclusive zlib headers) after the gzip file header but without the trailing crc32 checksum.

> Note: `level` was added in PHP 4.2, before PHP 4.2 gzencode() only had the `data` and (optional) `encoding_mode` parameters..

The resulting data contains the appropriate headers and data structure to make a standard .gz file, e.g.:

Example 1. Creating a gzip file
    <?php
        $data = implode("", file("bigfile.txt"));
        $gzdata = gzencode($data, 9);
        $fp = fopen("bigfile.txt.gz", "w");
        fwrite($fp, $gzdata);
        fclose($fp);
    ?>

For more information on the GZIP file format, see the document: GZIP file format specification version 4.3 (RFC 1952).

See also gzcompress(). gzuncompress(), gzdeflate(), gzinflate().

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