PHP | hash_file( ) Function

The hash_file() function is an inbuilt function in PHP which is used to generate a hash value using the contents of a given file.

Syntax:

string hash_file( $algo, $file, $raw_opt )

Parameters: This function accept three parameters as mention above and describe below.

• $algo: It is the required parameter which specifies the selected hashing algorithm.
• $file: This parameter is used to hold the file url to be hashed.
• $raw_opt: If the parameter is set to true then output will be raw binary data and if the parameter is set to False then output will be lowercase hexits.

Return Value: This function returns a string containing the calculated message digest as lowercase hexits.

Below programs uses the file gfg.txt and contents of the file are:

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Below programs illustrate the hash_file() function in PHP:
Program 1:

<?php

// PHP program to illustrate
//  hash_file function


// Create a file to calculate hash of
file_put_contents('gfg.txt', 'GFG');

// Display Result
echo hash_file('md5', 'gfg.txt') . "</br>";
?>

Output:

083de2341fd19dce0de9e60f3e9a8e0d

Program 2:

<?php

// PHP program to illustrate
//  hash_file function


// Create a file to calculate hash of
file_put_contents('gfg.txt', 'SUDO PLACEMENT');

// Display Result
echo hash_file('md5', 'gfg.txt') . "</br>";


// Create a file to calculate hash of
file_put_contents('gfg.txt', 'GCET');

// Display Result
echo hash_file('sha1', 'gfg.txt');
?>

Output:

083de2341fd19dce0de9e60f3e9a8e0d
a287a6ac47afec4140253a10b8a4c9c1e4f7a45e

Reference: http://php.net/manual/en/function.hash-file.php