Thank you very much for your help.
 
I was able to figure out a way to make this simple package work and was
able to build a more useful and complex package as well. I am however
left with one problem when building that more complex package. Before I
go on with this issue, here is how I solved my initial problem:
 
After creating an R package directory structure, I included in the \src
directory my test.c file containing the following C code:
 
#include <stdio.h>
#include <nag.h>
#include <nagg05.h>
 
void test()
{
  long i;
 
  g05ccc();
  for(i=0;i<10000;i++)printf("Hello the world - NAG random number:
%lf\n",g05cac());
 
}
 
and a test.R file in the \R directory with the following R code:
 
.First.lib<-function(lib,pkg){
  library.dynam("test",pkg,lib)
}
 
.Last.lib <- function(libpath)
{
  library.dynam.unload("test",libpath)
}
 
gotest <- function()
  {
    .C("test")
    return(0)
  }
 
Based on Duncan Murdoch's recommendation, I then included a Makefile.win
file containing the following code:
 
test.dll : test.obj test.def
      link /dll /def:test.def /out:test.dll test.obj nagcsmt-mkl.lib
mkl_s.lib mkl_def.lib mkl_lapack.lib advapi32.lib netapi32.lib Rdll.lib
test.obj : test.c
      cl /MT /Ox /D "WIN32" /c -I"C:\Program Files\Numerical Algorithms
Group\CLW3207DA\include" test.c
 
I inspired myself from the readme.package file in the \R folder to write
these lines. Note that this makefile relies on a .def file which
indicates (at least this is my understanding of what it does) to R how
to find the test() C function in the test.dll. Before realizing the need
for this .def file, I omitted this file in the Makefile.win. As a
consequence I was able to build and install the package successfully,
i.e. without error message. However, when I tried to use it, R would
give me an error message suggesting that it could not find the test() C
routine.
 
Here is the code included in the test.def that I placed in the \src
directory:
 
LIBRARY test
EXPORTS
 test
 
After doing so I was able to successfully build, install and use the R
package that I called "test":
 
C:\Rdevelop>Rcmd INSTALL test
 
 
---------- Making package test ------------
  adding build stamp to DESCRIPTION
  running src/Makefile.win ...
cl /MT /Ox /D "WIN32" /c -I"C:\Program Files\Numerical Algorithms
Group\CLW3207DA\include" test.c
Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 12.00.8804 for
80x86
Copyright (C) Microsoft Corp 1984-1998. All rights reserved.
 
test.c
link /dll /def:test.def /out:test.dll test.obj nagcsmt-mkl.lib mkl_s.lib
mkl_def.lib mkl_lapack.lib advapi32.lib netapi32.lib Rdll.lib
Microsoft (R) Incremental Linker Version 6.00.8447
Copyright (C) Microsoft Corp 1992-1998. All rights reserved.
 
   Creating library test.lib and object test.exp
  ... done
  installing DLL
  installing R files
  installing data files
  installing man source files
  installing indices
  not zipping data
  installing help
 >>> Building/Updating help pages for package 'test'
     Formats: text html latex example chm
  f                                 text    html    latex   example
  adding MD5 sums
 
* DONE (test)
 
 
Now, using the same methodology I was able to build a more complex R
package successfully. The package works very well and returns the
answers I expect except that it does not display in the R interface the
things that the C program requests to be printed.
 
I this more complex package, I use several calls to "printf" in the C
program of that package. I also use "cat" calls in the R function of the
package. It turns out that all calls to "cat" work without problem
whereas calls to "printf" always fail (i.e. nothing is displayed in R).
What is also interesting is that the calls to "printf" are however all
displayed after I quit R. So it looks like it is R that does not allow
my C program to display text on the standard output. This is very
surprising because the simple package "test" I described above does work
just fine even though it also uses "printf" calls.
 
Again, any suggestions on what can cause this problem or any
recommendation on how to solve it will be greatly appreciated.
 
Thank you.
 
Romain
 
 
 
 

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