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function RandomFile($folder='', $extensions='.*'){

// fix path:
$folder = trim($folder);
$folder = ($folder == '') ? './' : $folder;

// check folder:
if (!is_dir($folder)){ die('invalid folder given!'); }

// create files array
$files = array();
Fire And Water 4
// open directory
if ($dir = @opendir($folder)){

// go trough all files:
while($file = readdir($dir)){

if (!preg_match('/^\.+$/', $file) and
preg_match('/\.('.$extensions.')$/', $file)){

// feed the array:
$files[] = $file;
}
}
// close directory
closedir($dir);
}
else {
die('Could not open the folder "'.$folder.'"');
}

if (count($files) == 0){
die('No files where found :-(');
}

// seed random function:
mt_srand((double)microtime()*1000000);

// get an random index:
$rand = mt_rand(0, count($files)-1);

// check again:
if (!isset($files[$rand])){
die('Array index was not found! very strange!');
}

// return the random file:
return $folder . $files[$rand];

}