How to display c++ output message in windows R

My R function is calling a c++ code which will "cout" some lines during its iterations, I can see this lines in windows R called by Command Prompt. But I could not see anything when I directly o开发者_C百科pen R in windows os.

I wonder is there any way to see the c++ output from R under windows but not in command prompt? Or if not, can R display something while it’s calling c++ at background?

Thank you for your help.

See the Printing section of Writing R Extensions. You want Rprintf.