What is the Liferay's Struts Controller servlet name?

Liferay uses Struts 1.2.x.  As part of liferay implementation liferay's team extended the struts default Action Controller servlet.

customized controller servlet is MainServlet

<servlet>
        <servlet-name>Main Servlet</servlet-name>
        <servlet-class>com.liferay.portal.servlet.MainServlet</servlet-class>
    ...
</servlet>

<servlet-mapping>
        <servlet-name>Main Servlet</servlet-name>
        <url-pattern>/c/*</url-pattern>
    </servlet-mapping>




public class MainServlet extends ActionServlet {
....

}