[Rd] Interfacing R and C++

[Sean Davis]

I have a single c++ file that contains a class and a "wrapper" function that
has C-like syntax for interacting with the Class.  Basically, this wrapper
function just makes an instance of the class and then organizes the data for
return to R.  

#include <math.h>

void myFunc(double *data, int *n, double *prm, double* intervals, int* max,
double *plot) {
...
}

myClass::myclass(...) {
...
}

My question is simple:  what goes inside the extern "C" {} block.  Should it
include only the #includes, those and the "wrapper" function, or the entire
.cc file?  The answer wasn't clear to me from the Writing R extensions
manual (probably due to my c++ ignorance--using someone else's code).

> sessionInfo()
R version 2.2.0, 2005-08-11, powerpc-apple-darwin7.9.0

attached base packages:
[1] "methods"   "stats"     "graphics"  "grDevices" "utils"     "datasets"
[7] "base"

I'm trying to use the .C interface and getting segmentation faults--probably
a bug in the code, but just wanted to make sure that it wasn't a simple
issue with the extern block.

Thanks,
Sean