php man page for hash_file

HASH_FILE(3)								 1							      HASH_FILE(3)

hash_file - Generate a hash value using the contents of a given file

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

DESCRIPTION
PARAMETERS
	      o $algo
		- Name of selected hashing algorithm (i.e. "md5", "sha256", "haval160,4", etc..)

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

	      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

	      Using hash_file(3)

	      <?php
	      /* Create a file to calculate hash of */
	      file_put_contents('example.txt', 'The quick brown fox jumped over the lazy dog.');

	      echo hash_file('md5', 'example.txt');
	      ?>

	      The above example will output:

	      5c6ffbdd40d9556b73a21e63c3e0e904

SEE ALSO
       hash(3), hash_hmac_file(3), hash_update_file(3), md5_file(3), sha1_file(3).

PHP Documentation Group 													      HASH_FILE(3)