R help - Jun 2004 - memory allocation and interrupts

Hi,
 
A recent discussion on the list about tryCatch and signals made me think
about memory allocation and signals in C extension modules. What happens
to the memory allocated by R_alloc and Calloc if the user pressed Ctr-C
during the call? R-ext doesn't seem to discuss this. I'd guess that
R_alloc is interrupt-safe while Calloc is not, but I am not sure. In any
case a paragraph in R-ext on signals would be helpful.
 
While looking around for interrupts handling in the code I came across
BEGIN_SUSPEND_INTERRUPTS macro in Defn.h file. Unfortunately, it is not
available via R.h or Rinternals.h. Am I missing something? If not, could
future releases of R make it available via, say, Rinternals.h?
 
Thanks,
Vadim

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On Fri, 11 Jun 2004, Vadim Ogranovich wrote:
> A recent discussion on the list about tryCatch and signals made me think
> about memory allocation and signals in C extension modules. What happens
> to the memory allocated by R_alloc and Calloc if the user pressed Ctr-C
> during the call? R-ext doesn't seem to discuss this. I'd guess that
> R_alloc is interrupt-safe while Calloc is not, but I am not sure. In any
> case a paragraph in R-ext on signals would be helpful.
Easy: such code is not interruptible by Ctrl-C (sic).  And that *is* in
R_exts.* (sic), even with an entry `interrupts' in its index!


-- 
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)
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