[syslinux] Read disk with open()/read()?

[Gordon Schumacher]

H. Peter Anvin <hpa at zytor.com> wrote on Sat, 15 Dec 2007 12:31:52 -0800:
> If you're keying on *data*, like strings, then you have to have a 
> dispatch function somewhere, which will pull in every single device 
> driver in any binary.
>
> Hence opendev(), which only pulls in the requested device drivers.
>   

Do you mean that with respect to being able to open a *specific* disk? 
I just was after the ability to read from the disk that syslinux is
currently running on, which doesn't seem require anything past the
INT22/19h call (at least not under isolinux, which is the only place
I've tested it).