XMExtensions define a source file name suffix to be processed. 'phpc' is the XMExtension which processes %.phpc files, using the PHP Command Line Interface. Run-time code must be inhibited from build-time evaluation.
// build-versus-run-time.php?user=greg&lang=es

// this code will be executed at build time
$build_date=date("l dS of F Y h:i:s A");

<title>phpc example: build versus run-time code execution</title>
This file was built on: <?= $build_date;?><br>

// register prerequisite file including run-time code:
phpc_add_prerequisites( $prerequisite_file );
// read in the run-time code file

<b class="comment">begin embedded run-time code</b><br>

    <?= PHP_OPEN_TAG;?>
    // this code will be executed at run time
    import_request_variables ("GPC");                
    echo ("user=$user\n<br>");
    echo ("language=$lang\n<br>");
    <?= PHP_CLOSE_TAG;?>

<b class="comment">end embedded run-time code</b><br>