Thanks all for your replies. I don't need to worry about poratability (for now anyway), and my set up will be relatively simple. Two linux boxes looking for a "command" file in a directory NFS mounted from an AIX box. The program picking up this file and passing it off to a FAX program will likely be perl. If one of the available modules looked to be feasible for this set up, I would try it. If not, there are a number of other approaches we could take, including something akin to what procmail does. In fact, it seems like we have implemented that scheme many times.