XOR a string 1 character at a time

[soadlink]

Hello I need some help with code where I could store a string as $string and then XOR it 1 character at a time by the phrase "gamespy".

So if I have HelloWorld for my string, I want to XOR the H, then the e, then the l.... and so on until the string is done. Then I want to echo the XOR conversions together. I am bascially trying to port the C code blow over to PHP, or even over to VB would be nice (just a way that will help me understand it)

but here is the original C code[code]void gamespyxor(u_char *data, int len) {
    u_char  gamespy[] = "gamespy",
            *gs;

    for(gs = gamespy; len; len--, gs++, data++) {
        if(!*gs) gs = gamespy;
        *data ^= *gs;
    }
}[/code]

[Barand]

You can access the ith character of a string using $string{$i}

eg
[code]
<?php
$string = 'HelloWorld';

$lens = strlen($string);

for ($i=0; $i < $lens; $i++) {
    echo $string{$i} . '<br />';
}
?>
[/code]