# crc32

(PHP 4 >= 4.0.1, PHP 5)

crc32 — Calculates the crc32 polynomial of a string

### Description

int crc32 ( string `$str` )

Generates the cyclic redundancy checksum polynomial of 32-bit lengths of the `str` . This is usually used to validate the integrity of data being transmitted.

Because PHP's integer type is signed, and many crc32 checksums will result in negative integers, you need to use the "%u" formatter of sprintf() or printf() to get the string representation of the unsigned crc32 checksum.

### Parameters

`str`

  The data.

### Return Values

### Examples

Example#1 Displaying a crc32 checksum

This example shows how to print a converted checksum with the printf() function:

`<?php
$checksum = crc32("The quick brown fox jumped over the lazy dog.");
printf("%u\n", $checksum);
?>`

### See Also

- md5()
- sha1()