sending socket descriptor to another pid

Folks,

Socket(2) returns a file descriptor, used to send, write or read data
from the socket. A process calling socket can successfully create the
socket. I found there is a way to send the socket file descriptor to
another process and be able to read and write data as if it were the
original pid via the sendmsg call. I am now looking for examples on
how to write up a simple test case. Any pointers?

Thanks,
BEA

Beagle wrote:
> Folks,
>
> Socket(2) returns a file descriptor, used to send, write or read data
> from the socket. A process calling socket can successfully create the
> socket. I found there is a way to send the socket file descriptor to
> another process and be able to read and write data as if it were the
> original pid via the sendmsg call. I am now looking for examples on
> how to write up a simple test case. Any pointers?
>
> Thanks,
> BEA


I guess that it is impossible because someone file descriptor of a
process is is invalid in other process. The kernel uses two tables of
resources. The first table connects descriptors of process with
descriptors of kernel table. The second table is general for the kernel.

Daneel

Discovered a truly amazing book (again) which goes into depth
explaining and provides source code delivering exactly the result I
was after (WOW).

Advanced Programming in the UNIX Environment, Second Edition, Chapter
17, Advanced IPC, Section 17.6. An Open Server, Version 2

http://www.apuebook.com

Others had referenced the Linux kernel, net/core/scm.c


On Jul 8, 11:28 am, Daneel Yaitskov <rtfm.rtfm.r...@gmail.com> wrote:
> Beagle wrote:
> > Folks,
>
> > Socket(2) returns a file descriptor, used to send, write or read data
> > from the socket. A process calling socket can successfully create the
> > socket. I found there is a way to send the socket file descriptor to
> > another process and be able to read and write data as if it were the
> > original pid via the sendmsg call. I am now looking for examples on
> > how to write up a simple test case. Any pointers?
>
> > Thanks,
> > BEA
>
> I guess that it is impossible because someone file descriptor of a
> process is is invalid in other process. The kernel uses two tables of
> resources. The first table connects descriptors of process with
> descriptors of kernel table. The second table is general for the kernel.
>
> Daneel