You can use SET("TABLEPROMPT") to determine the current setting. You can also specify a startup value for TABLEPROMPT in the Config.fpw, the Visual FoxPro configuration file.
This feature is supported in COM server scenarios (MTDLL and DLL) where users do not have access to a user interface. SET TABLEPROMPT provides similar support in Visual FoxPro. You can use SYS(2335) - Unattended Server Mode to control modal states for COM servers.