Michael Smith wrote:
> OK, so does anybody know what sunrpc actually does? Everything I've
> read says "duh, it maps ports" Well, OK, I knew that. I'm looking for
> something more concrete.
I have used SunRPC. Programmed to it. Traced through large parts of
it in a debugger. Written XDR objects. Argued with NFS maintainers
about bugs in it.
RPC == remote procedure call. You knew that. The idea is that it
makes it easier to put message passing into your application. That's
only partially true, it's pretty ugly.
NFS and its friends (mountd, lockd) rely on SunRPC a lot. So does
yp.
One component of SunRPC is portmapper (which was renamed to something
nonobvious in NIS+). Portmapper listens on one port, 111, according
to /etc/services, for SunRPC requests that say, 'What is the port for
some service?" The supported services are in /etc/rpc, and clients
ask for them by number. Portmapper sends back the reply, and the
client connects to the port that portmapper told it.
Check "rpcinfo -p" to see what services are registered on your
system. Mine has nothing registered except portmapper.
The port mapping part of it is really not much different from
/etc/services, except instead of the IANA assigning numbers from a 16
bit space, Sun assigns numbers from a 32 bit space, and portmapper
maps them down to the 16 bit space of TCP or UDP.
Look in /etc/rpc and see how nearly everything Sun have released
relies on RPC.
So what do you really want to know?
--
K<bob>
[EMAIL PROTECTED], http://www.jogger-egg.com/
