PHP Manual
Prev |  | Next

# VIII. Compression functions

This module uses the functions of zlib by Jean-loup Gailly and Mark Adler to transparently read and write gzip (.gz) compressed files. You have to use a zlib version >= 1.0.9 with this module.

This module contains versions of most of the filesystem functions which work with gzip-compressed files (and uncompressed files, too, but not with sockets).

# Small code example

Opens a temporary file and writes a test string to it, then it prints out the content of this file twice.

Example 1. Small Zlib example
    <?php
      $filename = tempnam('/tmp', 'zlibtest').'.gz';
      print "<html>\n<head></head>\n<body>\n<pre>\n";
      $s = "Only a test, test, test, test, test, test, test, test!\n";
      // open file for writing with maximum compression
      $zp = gzopen($filename, "w9");
      // write string to file
      gzwrite($zp, $s);
      // close file
      gzclose($zp);
      // open file for reading
      $zp = gzopen($filename, "r");
      // read 3 char
      print gzread($zp, 3);
      // output until end of the file and close it.
      gzpassthru($zp);
      print "\n";
      // open file and print content (the 2nd time).
      if (readgzfile($filename) != strlen($s)) {
              echo "Error with zlib functions!";
      }
      unlink($filename);
      print "<pre>\n</h1></body>\n</html>\n";
    ?>

Prev | Home | Next
cpdf_add_annotation | Up | gzclose