php man page for hash_hmac_file

HASH_HMAC_FILE(3)							 1							 HASH_HMAC_FILE(3)

hash_hmac_file - Generate a keyed hash value using the HMAC method and the contents of a given file

SYNOPSIS
       string hash_hmac_file (string  $algo, string  $filename, string	$key, [bool  $raw_output = false])

DESCRIPTION
PARAMETERS
	      o $algo
		-  Name  of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..) See hash_algos(3) for a list of supported algo-
		rithms.

	      o $filename
		- URL describing location of file to be hashed; Supports fopen wrappers.

	      o $key
		- Shared secret key used for generating the HMAC variant of the message digest.

	      o $raw_output
		- When set to TRUE, outputs raw binary data.  FALSE outputs lowercase hexits.

RETURN VALUES
	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.

EXAMPLES
       Example #1

	      hash_hmac_file(3) 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');
	      ?>

	      The above example will output:

	      7eb2b5c37443418fc77c136dd20e859c

SEE ALSO
       hash_algos(3), hash_hmac(3), hash_file(3).

PHP Documentation Group 													 HASH_HMAC_FILE(3)