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Date: Thu, 19 Jun 2003 13:04:26 +0000
From: Philip Reynolds <philip.reynolds@rfc-networks.ie>
To: freebsd-hackers@freebsd.org
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Subject: Re: struct ipc_perm
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Gary Jennejohn <garyj@jennejohn.org> 38 lines of wisdom included:
> 
> Dmitry Sivachenko writes:
> > Any ideas?
> > 
> 
> The usual way to handle this sort of change is to put any new structure
> elements at the end so that existing applications don't get confused.
> They simply aren't aware the new elements were added.
> 
> Of course, this can cause problems when the kernel does a copyout()
> using the new size but the application passed a pointer to
> storage which can only hold the old, smaller structure.

Yeh, recompiling any applications using it, should work.
They'll pick up the sizeof() the modified struct.

-- 
Philip Reynolds                      | RFC Networks Ltd.
philip.reynolds@rfc-networks.ie      | +353 (0)1 8832063
http://people.rfc-networks.ie/~phil  | www.rfc-networks.ie