Hi, Can you help me please. I must developp an application with the logiciel R. It 's an application for pricing. So I see it uses the langage C and I see on the net taht it 's possible in c++. Use C++ it 's better than C , we know it. However It says to use c++ with R , we must : " You need to do two things: (a) Write a wrapper to export the symbols you want to call from R as extern "C". (b) Include the C++ libraries in the link to make the DLL. Suppose X.cc contains your C++ code, and X_main.cc is the wrapper, as in the example in `Writing R Extensions'. Then build the DLL by (gcc) ...\bin\R CMD SHLIB X.cc X_main.cc or (VC++, which requires extension .cpp) cl /MT /c X.cpp X_main.cpp link /dll /out:X.dll /export:X_main X.obj X_main.obj or (Borland C++, which also requires extension .cpp) bcc32 -u- -WDE X.cpp X_main.cpp and call the entry point(s) in X_R, such as X_main. Construction of static variables will occur when the DLL is loaded, and destruction when the DLL is unloaded, usually when R terminates. Note that you will not see the messages from this example in the GUI console: see the next section. This example used to be in package cxx_0.0-x.tar.gz in the src/contrib/Devel section on CRAN, and could be compiled as a package in the usual way on Windows. " So it doesn't run , With C it 's ok but with c++ no no. I dont understand and don' t know how write this wraper, because Compilateur Visual C++ compile C too, so I don't need wraper? Too there is a black box used in Logiciel R it is writted in "R" with C it 'ok but with c++ it doesn't Can you help me please. Thank you very much [[alternative HTML version deleted]]