## DDE exchange protocol is available ONLY under Windows!
        ## Also, this cannot be run by examples() but should be OK when pasted
        ## into an interactive R session with the tcltk package loaded
        ## Here is how you can test these features under Windows
        options(use.DDE = TRUE)
        library(svIDE) # This should automatically start the
        # DDE server named 'TclEval SciViewsR', according to the option set
        
        # Get some data in the user workspace
        data(trees)
        a <- 1
        b <- "some text in the first instance of R"
        #######################################################
        # To test these functions in an external program, we need now
        # to start a second instance of R. In this second instance, enter:
        library(tcltk)
        .Tcl("package require dde")
        .Tcl("dde services TclEval {}")
        # You should get 'TclEval SciViewsR' in the list
        # if the server in the first instance is running
        
        # Now, request a calltip for the function 'ls'
        # This is done in two steps:
        # 1) Execute the command 'guiCallTip' with this code chunk as argument
        .Tcl("dde execute TclEval SciViewsR {guiCallTip {res <- ls(}}")
        # 2) Retrieve the calltip from the variable SciViewsR_CallTip
        .Tcl("dde request TclEval SciViewsR SciViewsR_CallTip")
        # Another way to trigger DDE commands (for programs that do not support
        # DDE is to use 'execdde.exe' of the tcltk2 package (see ?tk2dde)
        # It is also possible to copy the calltip to a file, or to the clipboard
        # by specifying it after the command (also the two additional arguments
        # have their default values changed)
        .Tcl("dde execute TclEval SciViewsR {guiCallTip {library(} clipboard TRUE 40 TRUE}")
        # Look at what is in the clipboard
        cat(readClipboard(), "\n")
        # The process is similar to get completion lists
        .Tcl("dde execute TclEval SciViewsR {guiComplete {iris$}}")
        .Tcl("dde request TclEval SciViewsR SciViewsR_Complete")
        # Get the list of variables in the user workspace of the first R instance
        # into the clipboard (use also the other arguments to get the type of objects)
        .Tcl("dde execute TclEval SciViewsR {guiComplete {} clipboard TRUE { - }}")
        # Look at what is in the clipboard
        cat(readClipboard(), "\n")Run the code above in your browser using DataLab