Generating random string

[Anon]

I have used the following function to generate a random password, but it just generates the same string - over and over. What's wrong?

function makepassword($length = 5)
{
// purpose: return a random password of length $length

srand( (double) microtime() );

$which = "";
$password = "";

for ($i=0; $i < $length; $i++) {
$which = rand(1, 3);

// character will be a digit 2-9
if ( $which == 1 ) $password .= rand(0,9);

// character will be a lowercase letter
elseif ( $which == 2 ) $password .= chr( rand(65, 90) );

// character will be an uppercase letter
elseif ( $which == 3 ) $password .= chr( rand(97, 122) );
}

return $password;

[kparker]

Probably just that your machine is too fast. I assume you're testing it in a manner similar to this:

for ($test = 0; $test &lt; 5; test++ )
&nbsp;&nbsp;&nbsp;{
&nbsp;&nbsp;&nbsp;echo makepassword(). "&lt;br&gt;";
&nbsp;&nbsp;&nbsp;}

The fix is to move the call to 'srand()' out of the function and call it once at the head of your main script. microtime() may pretend to give out time in millisecond resolution, but in actuality the increments can't be any bigger than the machine underlying clock-tick interrupt.

[Anon]

function makepassword($length = 5)
{
$password = substr(md5(time()),0,$length);
return $password;
}

This works by taking the current time and performing an MD5 hash on it. It is then chopped to 6 characters using the substr function.

[Anon]

oops,
the paramater that gets passed to the function is the length that you want the password to be, in this case the length will be 5 characters (not 6).

[Anon]

just one query

i we use the function password as u have given and if it happens that more than 1 happen to get a generated in this manner then wont it cause a problem

as time() when both click is same and md5 for it will also will be same

can ya correct me if am wrong
please
mandar