# Zlib Compression

# Introduction

This module enables you to transparently read and write gzip (.gz) compressed files, through versions of most of the filesystem functions which work with gzip-compressed files (and uncompressed files, too, but not with sockets).

> Note:

> PHP comes with a fopen-wrapper for .gz-files. More information is available in the section about zlib://.

- Installing/Configuring
  - Requirements
  - Installation
  - Runtime Configuration
  - Resource Types
- Predefined Constants
- Examples
- Zlib Functions
  - deflate_add — Incrementally deflate data
  - deflate_init — Initialize an incremental deflate context
  - gzclose — Close an open gz-file pointer
  - gzcompress — Compress a string
  - gzdecode — Decodes a gzip compressed string
  - gzdeflate — Deflate a string
  - gzencode — Create a gzip compressed string
  - gzeof — Test for EOF on a gz-file pointer
  - gzfile — Read entire gz-file into an array
  - gzgetc — Get character from gz-file pointer
  - gzgets — Get line from file pointer
  - gzgetss — Get line from gz-file pointer and strip HTML tags
  - gzinflate — Inflate a deflated string
  - gzopen — Open gz-file
  - gzpassthru — Output all remaining data on a gz-file pointer
  - gzputs — Alias of gzwrite
  - gzread — Binary-safe gz-file read
  - gzrewind — Rewind the position of a gz-file pointer
  - gzseek — Seek on a gz-file pointer
  - gztell — Tell gz-file pointer read/write position
  - gzuncompress — Uncompress a compressed string
  - gzwrite — Binary-safe gz-file write
  - inflate_add — Incrementally inflate encoded data
  - inflate_get_read_len — Get number of bytes read so far
  - inflate_get_status — Get decompression status
  - inflate_init — Initialize an incremental inflate context
  - ob_gzhandler — ob_start callback function to gzip output buffer
  - readgzfile — Output a gz-file
  - zlib_decode — Uncompress any raw/gzip/zlib encoded data
  - zlib_encode — Compress data with the specified encoding
  - zlib_get_coding_type — Returns the coding type used for output compression
- DeflateContext — The DeflateContext class
- InflateContext — The InflateContext class

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