Re: l4-ka, c++!

[Niels Möller]

"swin" <address@hidden> writes:

>       I have heard that hurd will discontinue current
> hurd-l4, and switch to l4-ka,but l4-ka is written in
> c++

Right, the current L4 version that we use is pistachio, from the
Karlsruhe L4 team. It's written in C++.

> but for a practical OS, do you think it will degrade efficiency?

Personally, I'm not very fond of C++, but as far as I understand, it's
a fairly restricted subset of C++ that's used in pistachio (e.g. no
"virtual" functions or exceptions or other dynamic features that have
a runtime cost in cpu or memory usage). One can think about it as C
with a more advanced preprocessor.

And that's only the microkernel, the core components (pun intended) in
user space will be written in plain C.

L4 is small enough, that if you really want to, you could write a new
implementation in assembler for your favourite cpu. But work like that
should wait until the L4 interfaces have matured. (I think there
exists a few assembler implementations for earlier versions of the L4
spec, anybody knows how small or big they are?)

/Niels