Path: utzoo!attcan!uunet!cme-durer!libes From: libes@cme-durer.ARPA (Don Libes) Newsgroups: comp.lang.c Subject: Re: implementing Dijkstra's guarded commands Keywords: in a serial environment, parallel to come Message-ID: <516@muffin.cme-durer.ARPA> Date: 16 Jul 88 18:38:22 GMT References: <515@muffin.cme-durer.ARPA> <8044@alice.UUCP> Organization: National Bureau of Standards, Gaithersburg, MD Lines: 23 In article <8044@alice.UUCP>, ark@alice.UUCP writes: > Dijkstra's guarded commands don't really allow for parallel > [ example deleted ] > Where's the parallelism? You can execute the guards in parallel, as long as they don't have side-effects. I noted this in the last paragraph of my posting, but I guess you missed it. I'll repeat it: In article <515@muffin.cme-durer.ARPA>, I wrote: > parallel execution of guards containing functions with side-effects > would be awful. (Fortunately, I don't believe I have to worry about > that particular problem.) In fact, I have never seen anyone using guards WITH side-effects. I think it is commonly understood that one of the benefits of Dijkstra's guarded commands is that the obvious nondeterminism makes it easy to speed up on a parallel machine. I have already received several elegant solutions to my question. I will post the best shortly. Don Libes cme-durer.arpa ...!uunet!cme-durer!libes