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Date: Sun, 24 Feb 2002 20:58:49 -0500 (EST)
From: Alexander Viro <viro@math.psu.edu>
To: Rusty Russell <rusty@rustcorp.com.au>
cc: Linus Torvalds <torvalds@transmeta.com>, mingo@elte.hu,
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On Mon, 25 Feb 2002, Rusty Russell wrote:

> > Note that getting a file descriptor is really quite useful - it means that
> > you can pass the file descriptor around through unix domain sockets, for
> > example, and allow sharing of the semaphore across unrelated processes
> > that way.
> 
> First, fd passing sucks: you can't leave an fd somewhere and wait for
> someone to pick it up, and they vanish when you exit.  Secondly, you

Yes, you can.  Please, RTFS - what is passed is not a descriptor, it's
struct file *.  As soon as datagram is sent, descriptors are resolved and
after that point descriptor table of sender (or, for that matter, survival
of sender) doesn't matter.