Prof Brian Ripley <[EMAIL PROTECTED]> writes: > 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!
The programmer might reenable interrupts though. This is not something that we have a precedence (nor a policy) for, but it has crossed my mind a couple of times. In some cases it should be possible to wrap time-consuming C code in a setjmp/longjmp construct. It's not possible to do it generally because all hell breaks loose if the C code calls back into R, but not all C code does that. Of course it is critically important that the code resets the interrupt handling to a sane state when it is done, so it would be nice if we could abstract a reasonably safe construction into a RUN_INTERRUPTIBLE() macro. -- O__ ---- Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
