> no i know /etc/copyright and /etc/motd
> but mean when u boot freebsd or dragonflybsd and a screen appears
> which asks for booting modewhether single or any other mode,

That would be the (second stage?) bootloader, obviously.

> beside
> these choices there is a devil logo created by ascii character (in
> FreeBSD) and a the dragonflybsd(in dragonflybsd)

No logo in any of NetBSD's bootloaders, AFAIK. Look at
src/sys/arch/*/stand/*boot* for more details (depends on what
architecture you're on and what bootloader you're using).

	Regards,
		-- Jachym Holecek