; TeX output 1996.03.05:1400-܍@U1pR%NH cmbx12Setting T{real-timeCSP!UwR%DtGGcmr17Jim7tDaqvies6R%NG cmbx121{Inutro=duction$b#R%XQ cmr12ThedlanguageandmoSdelsofCSPdzharvedundergoneagradualevrolutionsincethepublicationofR%the7 rstCSP0textbSook|Hoare's7}h! cmsl12CommrunicatingSequentialProScessesO¹(Prentice-Hall,Դ1985).R%Theforthcomingtextonreal-timeCSPwillprorvideforsomedegreeofstandardisation.R%InZparallel,w`wrehopSetoprovideastandardsetofmacrosforsettingdoScumentswhichuseCSPR%notation.5ThiswillallorwuserstoexchangedoScumentsinelectronicform,andwillformpartR%oftheuserinrterfacetothelanguagetoSols.R%TheHmacrosarede nedbryastyle lecalled߆T cmtt12zed-csp.sty.ThisshouldworkwithLDD"|{Ycmr8A_ٹT UE!X-2g cmmi12"/Pչ.R%Inquiries,suggestions,orcomplainrtsshouldbSeaddressedto%ҿJim.Davies@comlab.ox.ac.uk.R%Notechthatthisisafairlyquicrk xofthestyletoenablemyselfandotherstousetheimprovedR%facilitiesY6o eredbrythenewversionofLDD"A_ٹT 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xb\then(!R%externalcrhoiceb\extchoice*(% Tq lasy102R%inrternalchoiceb\intchoice*uR%hidingb\hide+nR%parallelb\parallel[A][B]Djd[!AjURB<˹]WjR%inrterleavingb\interleave)j,7j0NjR%sharingb\parallel[C] j$M"[)C]jR%recursionb\mu,X\spotPܘ"YX;URPR%timeoutb\timeout[t]#..)ft$DgR%transferb\transfer[t] .,ft$DgR%inrterruptb\interrupt)N4R%timerb\at*#@$FR%indexedexternalcrhoiceb\ExtchoiceQǍ(/$/TqG lasy102R%indexedinrternalchoiceb\IntchoiceQǍ(Q,!",G cmsy10u(R%indexedalphabSetparallelb\ParallelQ덍*QkR%indexedinrterleavingb\InterleaveQ덍'pj,={j1 HjR%2.2!8Parallelffcombinations @R%There{ZaresevreralwaystodenotetheparallelcombinationoftwoproScessesinCSPV.Firstly,R%wrecandescribSethesetofeventsupSonwhichtheymustcoSoperate:8e.g.,intheproScess􍍑PgUR!P0.s8(ThisformoftimeoutwasR%suggestedbryGuyLeducforhisversionoftimedLOTOS.)2VR%3{Mathematicalzlanguage$b#R%TheDsemanrticmoSdelsofCSPDcomewithagreatdealofnotationalbaggage.WVeneedtode 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