Execute command

// Execution of commands may hang on Windows XP for some programs,
// wmic.exe is one of them. The solution is to use a command like
// this "echo | command...". See Issue 124:
// https://code.google.com/p/phpdesktop/issues/detail?id=124

$output = shell_exec("echo | {$_ENV['SYSTEMROOT']}\System32\wbem\wmic.exe path win32_computersystemproduct get uuid");

if ($output) {
    echo "Command executed successfully.<br>";
    echo "Output: $output";
} else {
    echo "Command failed.";
}