The reason i had problems running C++ DLL's in R was that i had defined my functions using the WINAPI command, e.g. void __export WINAPI fname ( int x[10][2], int y[10] ) { .... .... } I thought i could use WINAPI so that the name of the function ("fname") would remain unchanged when called in R which it does, but it also implements the standard calling convention, (as opposed to the C calling convention) which was the source of my problems. Also my dll's weren't portable because I had dynamically linked in some libraries. james -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._