Re: network programming

Andrew Reilly <andrew-newspost@xxxxxxxxxxxxxxxxxxxxx> writes:

On Wed, 12 Dec 2007 05:52:40 +0100, Andreas Davour wrote:

Depends on what you want to do. Some libraries don't support "raw"
packets so if you need them you may have to use FFI to access the OS
API. However, only applications that need to monitor or control
networks at the link layer need to use raw packets. Virtually all
other applications can make due with IP datagrams or TCP streams.

That would be the reason to have the underlaying level written in
something more sensible than C, to not be dependant on FFI.

But, I guess I will not use raw packets soon anyway.

Inventing new protocols on the packet/datagram level you would actually
get by with "raw" packets?

There's also the issue of multiplexing/demultiplexing packets to
applications, in a multi-tasking operating system. Below the socket
layer you really want to be in the operating system, so that you can pass
packets to the applications that are waiting for them. (You might want
to have a look at how the Minix3 network stack works: it doesn't use the
Berkeley Sockets model: network connections appear in the filesystem name
space, where regular file operations work on them.)

I knew there was interesting things going on in Minix3. Thanks for
reminding me of that.

/Andreas

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