Gerald's ideas about a Compositional Programming book is a good one. It needs some extra work doing first: Now we have what we think are good compositional packages in Java (JCSP and CJT), would someone please 'knock one up' for Posix threads? Of course, I'm joking about just knocking one up just like that. But the point is that Posix threads are widely used in industry and are held in some esteem, because they are standardised (errm ... not because they're good!) A CSP library built upon them would clearly benefit the cause of persuading people to adopt a compositional approach, and also would naturally be portable to a wide range of Posix target systems. A suggested solution might be a C++ equivalent of the core classes in JCSP using Posix.4a mutexes and condition variables. If I understand correctly, these operate rather similarly to Java monitors. Or is all this too hard to do? ;-) Rick -- Richard Beton B.Sc. C.Phys. M.Inst.P. Roke Manor Research Limited (http://www.roke.co.uk/) --------- Standard Disclaimer about my own views etc etc -------- --------- My mail client accepts rich text (HTML) mail -------- Welsh Highland Railway: http://www.whr.co.uk/WHR/WHR.html