1XEROX1108USERSGUIDE3.THEFILESYSTEMIntroductionThe1108harddiskfilesystemisdesignedtoprovideInterlisp-Duserswithaflexiblemechanismforstoringandaccessingfiles.Likethefilesystemsforthe1100andthe1132,the1108filesystemsupportssuchfeaturesasrandomaccessandversionnumbersonfiles.Inaddition,the1108localfilesystemsupportsahierarchicalnamingstructureforfiles.DiskPartitionsTheharddiskusedwiththe1108maybepartitionedintoupto10regionscalledlogicalvolumes.Logicalvolumesarelikedirectoriesonthediskdevice:theymaybeusedtoholdInterlispvirtualmemories,Interlispfiles,Mesafiles,orStarfiles.YoucanpartitionthediskwiththeInstallationUtilityfloppyorwithOthello.Becausepartitioningtheharddiskerasesallitscontents,youareadvisedtopartitionthediskappropriatelybeforestoringanythingonit.Otherwise,youwillhavetooff-loadallfilesfromthedisk,repartitionit,andthencopythefilesbacktothedisk.AlthoughanInterlispvirtualmemoryfilecancoexistonalogicalvolumewithotherfiles,itisgenerallyadvisabletogiveeachvirtualmemoryfilealogicalvolumethatitdoesnotsharewithanythingelse.Otherwise,theresultingfragmentationadverselyaffectsswappingperformance.AlogicalvolumeintendedtocontainanInterlispvirtualmemoryshouldbebetween8,000diskpages(4megabytes)and64,000pages(32megabytes)long.Thecloserto64,000pagesyoucanmakeyourvirtualmemoryvolumethebetter,providedthereisstillenough q?` p` q?` g_p`2~q`X2~3Cr`#,#3C3C3C+;233\0Zv "%&+33Z0Y7T""&&t)~+.'33Y70W[!Q%(V,0.33W0U# %+g033U0TE3),""$v*_,0733TE0RyKG s (e-33R0PJPw`]PPJu`J,G3CJ3C3CJv`iJ3CJI HIH}u`Hl,#3CH}3C3CH}0Eq`XG7!$'x*s,f 33E0D1a}##D1xD1(1-D1qD1.>.33D10B[ $%&1(+033B0@$:!',33@0?? #%),-033??0=0 "u"u=x= )-P=q=-133=0;;x;#;q;C"G *E-033;0:M!Y$4&,7-33:M08 %)* 02333807 k("#)*-1?33705[ !$(+7.\2335[033w`]3300q`Xb^$-)+.3300/Oi"&*q+-m33/O0-}!I%+Z-/33-0,y"&*!0O333,0*] #f -733*]0(3 'M( ).33(0' #6)H.&33'0%k"%*-+ 33%k0#  (]+,u/\33#0""&x).'33"0 yZ<%)+|.h33 y- q?`2XEROX1108USERSGUIDETHEFILESYSTEMspaceonthediskforanyothervolumesyoumightneed.TheIntermezzofilesystem(unlikeitspredecessors)allowsInterlispuserfilestocoexistonalogicalvolumewithMesaorStarfiles.SoitisnolongernecessarytohaveaspeciallogicalvolumegivenovertoLispuserfiles,thoughyoucanstillhaveoneifyoulike.NotethattostoreInterlispfilesonalogicalvolume,youmustcreateaLispdirectoryonthatvolume(seebelowforinstructions).FileSystemUtilityFunctionsSolongasthereisalogicalvolumewithaLispdirectoryonit,youwillhavealocaldiskdevicecalled{DSK}.ThisdevicecanbeusedfromwithinInterlisp-Djustlikethe{DSK}deviceonthe1100andthe1132,exceptthatitsupportsahierarchicalnamingstructureforfiles.IfyoudonothavealogicalvolumewithaLispdirectoryonit,Interlispemulatesthe{DSK}devicebyacoredevice.(AcoredeviceisafiledevicewhosebackingstoreisentirelywithintheLispvirtualmemory.)However,thiscausesthreeproblems.(a)Thecoredeviceprovideslimitedscratchspaceforsomesystemprograms;(b)whenrunningGREET,Interlispfailstofind{DSK}Init.Lispandhastopromptyouforaninitfile;and(c)sincethecoredeviceiscontainedinvirtualmemory,it(andthefilesstoredonit)canlastonlyaslongasyoukeepyourvirtualmemoryimage.TocreateaLispuserfiledirectoryonalogicalvolume,call(CREATEDSKDIRECTORYVolumeName)[Function]CREATEDSKDIRECTORYaffectsonlythespecifiedvolume,and(unlikepreviousversionsofthefilesystem)doesnotaffectMesaorStarfilesinthe3 y gq`Xbr`#,#3C3C3f3f!hFileNameThusthefileInit.LisponthevolumeLispFileswouldbecalled{DSK}Init.Lisp.3 gq`Xbr`#,#3C3C3f3f!h/033I0Hn%')+,033H0F`0";' *F`0Ce@%,033C0B@&m #%(g.Q33B@0@ #=&r)+.H333@0>d$?+/33>0=N $ +133=N0;1BZ#% .1?33;0:> %%,y-C33:08\ i & &u))./3338\0660u`0,G3C03C3C0v`i03C0/ )k 0/.u`.o,#3C.3C3C.0+q`XO` $P%)y/2~33+0*4!v#(q-o-1433*40(7(0&d&x&*&q&*&0#4!$f)g/p33#0!F)9))!# q?`5XEROX1108USERSGUIDETHEFILESYSTEMInaddition,youcanindicatesubdirectoriesusingthe>characterinfilenamestodelimitsubdirectorynames.Subdirectoriesallowyoutogroupfilestoafinerdegreeofgranularity.Fileswithsubdirectoriesarewritten{DSK}SubDir1>...>SubDirN>FileNameForexample,supposeyouhadafileLRdesign.TEditonthesubdirectoryParserGeneratoronthesubdirectoryCompileronthedirectory(logicalvolume)LispFilesoftheharddiskdevice.Itsnamewouldbewritten{DSK}Compiler>ParserGenerator>LRDesign.TEdit.Youcandefaultdirectorynamesforthe1108harddiskinanunusualbutsimpleway.Thatis:ifthefiledoesnothaveasubdirectoryandyouleaveoutthedirectory(logicalvolume)name,thedirectorydefaultstothenextlogicalvolumethathasaLispdirectoryonit,includingorafterthevolumecontainingthecurrentlyrunningvirtualmemory.ThusifyourdiskhasthelogicalvolumesLisp,Tajo,andLispFiles,andtheLispvolumecontainstherunningvirtualmemory,andonlytheLispFilesvolumehasaLispdirectoryonit,then{DSK}Init.Lispreferstothefile{DSK}Init.Lisp.Alltheutilityfunctionspresentedabovedefaultlogicalvolumenamesinasimilarway,exceptforthosethatcan't,suchasCREATEDSKDIRECTORY.IfyouwanttofindoutwhatthedefaultLispdirectoryis,call(DIRECTORYNAME'{DSK})ThisdefaultingconventionisnecessitatedbyseveralpartsoftheInterlispsystemthatcreatescratchfilesonthedevice{DSK}withoutspecifyingadirectory(logicalvolume).)! gq`X2~3Cr`#,#3C3C3Ca -_",%+1?33>0=Q# #&*-33=Q0;lW#*\-0n33;0: +&+1a33:08_#$3&)@-W338_06q"P',02}33605"=&)-133503m#$M%(,S./13333m01%'i))1w`]1)10.zq`X $'.z0,*  &!(o 133,0*Z &+/=33*Z0(O@A#*', 33(0&MNS#&w`]&#&R q?`=6XEROX1108USERSGUIDETHEFILESYSTEMDiskScavengingUnlikepreviousreleases,Intermezzoprovidesfulldisk-scavengingservicetoguardagainsttheunlikelyeventoffilesystemfailure.Therearetwoclassesoffilesystemfailure:Lispdirectoryfailureandlower-level(Pilot)failure.ScavengingserviceforLispdirectoriesisprovidedbySCAVENGEDSKDIRECTORY;scavengingforPilotisprovidedbyeitherOthelloortheInstallationUtility.Pilotfailuresmanifestthemselvesas"HARDDISKERROR"breakswithinLisp.Tofixsuchafailure,returntothetoplevel,logoutofLisp,getintoeitherOthelloortheInstallationUtility,usetheScavengeoptiononthelogicalvolumeinquestion,andthenrebootLisp.Lispdirectoryfailuresshowupasinfiniteloopingorotheraberrantbehaviorwhilethesystemisdoingadirectorysearchorenumeration.Torepairthedirectory,returntothetoplevelandcall(SCAVENGEDSKDIRECTORYVolumeName)[Function]Ifyouhaveanydoubtaboutwhichlogicalvolumestoscavenge,scavengethemall.Ifyouarenotsurewhichscavengertouseonavolume,usethemboth,Othello(ortheInstallationUtility)first,thenrunSCAVENGEDSKDIRECTORY.Neitherscavengerharmsanintactvolume.#& fw`]q`Xbr`#,#3C3C3f3f!h%%>x> . >q>3C3C>&=, =,0:T $)G-33:09 !A$''(+-0x339 07fOA!u#o$),|03B7fx7f337f055q5G##5x5 $(|5q5)-o133504&' ,33402P{iN!H2Pw`]2P!H2P00Oy`i00O q?`  TIMESROMAN   HELVETICA  HELVETICA  CLASSIC  HELVETICA  HELVETICA HELVETICA HELVETICA HELVETICA HELVETICA ~GACHA!'Oj/*(e,{ERIS}INTERMEZZO>DOC>LOCALFILE.PRESS;1SANNELLA18-Mar-85 13:33:01