str_pad(3) [php man page]

STR_PAD(3)								 1								STR_PAD(3)

str_pad - Pad a string to a certain length with another string

SYNOPSIS

       string str_pad (string  $input, int  $pad_length, [string  $pad_string = " "], [int  $pad_type = STR_PAD_RIGHT])

DESCRIPTION

	This  functions  returns  the  $input string padded on the left, the right, or both sides to the specified padding length. If the optional
       argument $pad_string is not supplied, the $input is padded with spaces, otherwise it is padded with characters from $pad_string up  to  the
       limit.

PARAMETERS

	      o $input
		- The input string.

	      o $pad_length
		- If the value of $pad_length is negative, less than, or equal to the length of the input string, no padding takes place.

	      o $pad_string
		-

	      Note

		      The  $pad_string	may be truncated if the required number of padding characters can't be evenly divided by the $pad_string's
		     length.

	      o $pad_type
		- Optional argument $pad_type can be STR_PAD_RIGHT, STR_PAD_LEFT, or STR_PAD_BOTH. If $pad_type is not specified it is assumed	to
		be STR_PAD_RIGHT.

RETURN VALUES

	Returns the padded string.

EXAMPLES

       Example #1

	      str_pad(3) example

	      <?php
	      $input = "Alien";
	      echo str_pad($input, 10); 		     // produces "Alien     "
	      echo str_pad($input, 10, "-=", STR_PAD_LEFT);  // produces "-=-=-Alien"
	      echo str_pad($input, 10, "_", STR_PAD_BOTH);   // produces "__Alien___"
	      echo str_pad($input, 6 , "___");		     // produces "Alien_"
	      ?>

PHP Documentation Group 														STR_PAD(3)

HASH(3) 								 1								   HASH(3)

hash - Generate a hash value (message digest)

SYNOPSIS

       string hash (string  $algo, string  $data, [bool  $raw_output = false])

DESCRIPTION

PARAMETERS

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

	      o $data
		- Message to be hashed.

	      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.

CHANGELOG

       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 5.4.0	|						    |
       |	|						    |
       |	| The tiger  algorithm	now  uses  big-endian  byte |
       |	| ordering. See also example below.		    |
       |	|						    |
       +--------+---------------------------------------------------+
EXAMPLES

       Example #1

	      A hash(3) example

	      <?php
	      echo hash('ripemd160', 'The quick brown fox jumped over the lazy dog.');
	      ?>

	      The above example will output:

	      ec457d0a974c48d5685a7efa03d137dc8bbde7e3

       Example #2

	      Calculate pre PHP-5.4 tiger hashes with PHP-5.4 and higher

	      <?php
	      function old_tiger($data = "", $width=192, $rounds = 3) {
		  return substr(
		      implode(
			  array_map(
			      function ($h) {
				  return str_pad(bin2hex(strrev($h)), 16, "0");
			      },
			      str_split(hash("tiger192,$rounds", $data, true), 8)
			  )
		      ),
		      0, 48-(192-$width)/4
		  );
	      }
	      echo hash('tiger192,3', 'a-string'), PHP_EOL;
	      echo old_tiger('a-string'), PHP_EOL;
	      ?>

	      Output of the above example in PHP 5.3:

	      146a7492719b3564094efe7abbd40a7416fd900179d02773
	      64359b7192746a14740ad4bb7afe4e097327d0790190fd16

	      Output of the above example in PHP 5.4:

	      64359b7192746a14740ad4bb7afe4e097327d0790190fd16
	      146a7492719b3564094efe7abbd40a7416fd900179d02773

SEE ALSO

       hash_file(3), hash_hmac(3), hash_init(3), md5(3), sha1(3).

PHP Documentation Group 														   HASH(3)