php file exist
<?php
$filename = '/path/to/foo.txt';
if (file_exists($filename)) {
echo "The file $filename exists";
} else {
echo "The file $filename does not exist";
}
?>
Source: www.php.net
php check if file exists
if (!file_exists('http://mysite.com/images/thumbnail_1286954822.jpg')) {
$filefound = '0';
}