[R-SIG-Mac] Forking issues in Mavericks

[Simon Zehnder]

Same system, no error (on the shell). Debugging parallel processes is in general not easy - here is a thread on this using lldb: http://stackoverflow.com/questions/14746315/how-to-attach-to-child-process-in-lldb. But first hope for an answer of a more experienced list user, who possibly knows how the processes are actually forked.

Are you sure, that you call just these commands? Or did you use these for a simple example? Usually the error comes up from the Core Foundation library, if a child process tries to fork unsafely.

Regarding the your problems with X11 though the answer from Steve sounds like a very good guess.

Best Simon
 
On 29 Oct 2013, at 20:08, Jeroen Ooms <jeroen.ooms at stat.ucla.edu> wrote:

> The following works in Linux and OSX 10.8 but in OSX 10.9 it results
> in a "__THE_PROCESS_HAS_FORKED_AND_YOU_CANNOT_USE_THIS_COREFOUNDATION_FUNCTIONALITY___YOU_MUST_EXEC__()":
> 
> library(parallel)
> library(httr)
> myfork <- mcparallel(GET("https://api.github.com/users/hadley/repos"))
> out <- mccollect(myfork)
> 
> I've seen this error before when trying to access X11 from inside a
> forked process. In this case it seems to be related to SSL, but I'm
> not quite sure how to further debug this in 10.9 (lldb anyone?). What
> exactly might be triggering this error?
> 
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