In src/emu/ui/ui.c:
In the function void ui_manager::display_startup_screens(bool first_time, bool show_disclaimer):
<br /> // disable everything if we are using -str for 300 or fewer seconds, or if we're the empty driver,<br /> // or if we are debugging<br />// if (!first_time || (str > 0 && str < 60*5) || &machine().system() == &GAME_NAME(___empty) || (machine().debug_flags & DEBUG_FLAG_ENABLED) != 0)<br /> show_gameinfo = show_warnings = show_disclaimer = show_mandatory_fileman = FALSE;<br />
The if line is the one that needs to be commented out, as per the code above. It will make MAME always execute the second line, which sets all the show variables to false.