[cap-talk] Piping capability communication, data vs. descriptor capability strengths

[John Carlson]

Wouldn't you have to create something in the ambient authority  
environment to get this to work?  What if another process owned by the  
same user was snooping on your PF_UNIX sockets?

I'd be interested in contribution to a C++ wrapper.  I've done a lot  
of TCP programming and a little UDP programming.  The only use of UNIX  
sockets that I recall was a way to write to the console input (behind  
locked doors in those days) on BSD 4.2 back in the mid '80s.

John

On Feb 27, 2009, at 7:06 AM, Rob Meijer wrote:

> On Fri, February 27, 2009 09:21, Jed Donnelley wrote:
>
>> Even in Unix I've heard that open file descriptors can be sent
>> through a pipe.  If that's so, what's the syntax (e.g. as above) look
>> like?  How are the descriptors sent and received specified (by the
>> sender on sending and by the OS on receiving to the receiver)?
>
>
> Datagram sockets of the PF_UNIX type can be used to communicate file
> descriptors using sendmsg/recvmsg. The man pages are a bit short on
> documentation on this, and the API requires you to use nasty MACRO's  
> in
> order to be portable, but if you can step past this, UNIX domain  
> sockets
> can be a great way to do IPC.
>
> I have been planning to write a C++ wrapper for it looking if  
> combining it
> with select and C++ functors could provide a more friendly  
> interface, but
> haven't gotten to more than a few partial experiments yet. This list  
> tends
> to be a bit hostile towards C/C++ as languages, but if anyone here is
> truly interested in this and willing to work on it with me, I may  
> pick it
> up again and see how far it gets us.
>
>
> Rob
>
> _______________________________________________
> cap-talk mailing list
> cap-talk at mail.eros-os.org
> http://www.eros-os.org/mailman/listinfo/cap-talk