Thanks to everyone who answered my query about dup2(). Although some people had invented their own version of the function, the easiest solution seemed to be the following: dup2(arg1,arg2) is replaced by fcntl(arg1,F_DUPFD, agr2). You must use the header file fcntl.h for fcntl(). Thanks again, Jeff Turner AT&TIS Labs ihnp4!drux3!druca!jt