Custom Manager Pages: How to Submit Variables to the Controller File?

<?php
$docId = ##; // set to the ID of the resource
$tvId = ##'; .. set to the ID of the TV

$tv = $modx->getObject('modTemplateVar',  $tvId);

$tv->setValue($docId, 'Value');
$tv->save();

$fieldstxt = array();
$fieldstxt['pagetitle'] = $mailingname."-txt";
$fieldstxt['alias'] = $mailingname."-txt";
$fieldstxt['template'] = '52';
$fieldstxt['parent'] = $idofnewresource;

$response = $modx->runProcessor('symlink/create', $fieldstxt);

$fields = array();

$fields['pagetitle'] = 'MyPage';
$fields['parent'] = $parentId;
$fields['content'] = $targetId;
//etc.

$resource = $modx->newObject('modSymlink', $fields);
$resource->save();

$fields['content'] = $targetId;
//etc.

$resource = $modx->newObject('modSymlink', $fields);
$resource->save();

$object = $response->getObject();
$idofnewresource = $object['id'];

$id = last_insert_id();

// or

$id = mysql_insert_id();

Call to undefined function last_insert_id()