(PHP 5 >= 5.1.2, PECL hash >= 1.1)
hash_hmac_file — Generate a keyed hash value using the HMAC method and the contents of a given file
Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..)
URL describing location of file to be hashed; Supports fopen wrappers.
Shared secret key used for generating the HMAC variant of the message digest.
When set to TRUE, outputs raw binary data. Default value (FALSE) outputs lowercase hexits.
Returns a string containing the calculated message digest as lowercase hexits unless raw_output is set to true in which case the raw binary representation of the message digest is returned.
Example #1 hash_hmac_file() example
<?php
/* Create a file to calculate hash of */
file_put_contents('example.txt', 'The quick brown fox jumped over the lazy dog.');
echo hash_hmac_file('md5', 'example.txt', 'secret');
?>
上例将输出：
7eb2b5c37443418fc77c136dd20e859c