Message-ID: <Pine.LNX.4.64.0704151945120.11794@gannet.stats.ox.ac.uk>
Date: 2007-04-15T19:09:56Z
From: Brian Ripley
Subject: save() and interrupts
In-Reply-To: <59d7961d0704151101w2e892a98r81038a7a336a2ec1@mail.gmail.com>
On Sun, 15 Apr 2007, Henrik Bengtsson wrote:
> are there any (cross-platform) specs on what the saved filed is if
> save() is interrupted, e.g. by a user interrupt? It could be
> non-existing, empty, partly written, or completed.
My understanding is that you cannot user interrupt compiled code unless it
is set up to check interrupts. Version 2 saves are done via the internal
saveToConn, and I don't see any calls to R_CheckUserInterrupt there. So
you only need to worry about user interrupts in the R code, and that has
an on.exit action to close the connection (which should be executed even
if you interrupt). Which suggests that the file will be
non-existent
empty
complete
and the first two depend on interrupting in the millisecond or less before
the compiled code gets called.
For other forms of interrupts, e.g. a Unix kill -9, the file state could
be anything.
--
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UK Fax: +44 1865 272595