TOPIC: NET_NAME(), THE NETNAME() SUBSTITUTE
AUTHOR: DON POWELLS
DATE: 13 Jan 1988
TEXT:
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NET_NAME(), THE NETNAME() SUBSTITUTE Published: 13 Jan 1988
Don Powells Copyright (c) 1988, Nantucket Corp.
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The NETNAME() function does not return anything in the Summer 87
version of Clipper. I wrote the function below to replace it as an
interim solution. It is called NET_NAME() and is invoked in the
same manner as the original function. The source code for the
assembly function and a Clipper test program which calls it are
included in this doc--is invs LlipStion. The source code for the
assembly function and a Cl0ner asEhME() fu4aich cTher0)s1i= m1tPpd a o) frs doc-fXT:
----------------------tasqlCn r nS hME() a Cl0:dMeEs docN[)-----LS=on and a CXnner as|
0sEn0mME(nS72UcoIhe sour.C() fu4tWno1988, Ft--------------2U1988
on 70/on and oM-O and a ClY70ttion& N) in t NETNAME() y function nd a Clippei0nd a 7or the
aVDNh. EUa 988ID ) fu LRewewewi= u0tID ) fu LRK/ID ) f
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0sEn0mME(nS72UcoIhe sour.C() fu4tWno1988, Ft--------------2U1988
on 70/on and oM-O and a ClY70tsRLaLh------Nt0tsRSoh9fn--------------------------------

The N--------1e(), TAReE- cflished: 1 a EE- b70tsRLaLCALLewewewLaLotrP,4fn--TERMIN0mME(nSOPLaLCC() fuOPLaLC() fuOPLaLe(), TOPLaL7ewon and a CXnne88P5tr88nwtOs88T---72UIhesour.Tand.PRGhesoW)-- -------AhME() a Cl0:dhesoOswritten988
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RLOCK()nsru:"Tr-Once" Aro-ch:IF RLOCK()EwtREPLACEn Xeld1 WITHm_ Xeld1EwtREPLACEn Xeld2 WITHm_ Xeld2
ENDIF
onsa(s orgo REPLACE aloge--i c-lok
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IF/ENDIFaDO/ENDDOrarran/ss,ron on an defis REC_LOCK()fudhLOCKS.PRGrour X:"RtryFornv a" Aro-ch:DOWHILE .NOT.RLOCK() o o o IF REC_LOCK(0)EwtINKEY(.5) o o o -OR-o REPLACEn Xeld1 WITHm_ Xeld1EENDDOo o o o o o o REPLACEn Xeld2 WITHm_ Xeld2
REPLACEn Xeld1 WITHm_ Xeld1 o o ENDIF
REPLACEn Xeld2 WITHm_ Xeld2
n ae: hINKEY(.5)paon isimporta.pspaNesh---work
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onAutumn '86) vid fr ti-e li-t. A slighmodificatpmt aon a smsaPut eINKEY(.5)toworkby examisevalunireturs Iitindicatsesaape keyn ha aben sruk, exnt e:IF INKEY(.5)= 27EwtEXIT
ENDIF
IMININnd.PRGmodifinis cals REC_LOCKER(e nn cod frou--o--trestrategin abeoes:"RtryFXxeTi-e" Aro-ch: REC_LOCK(2) o o o o && try or 2seds"RtryT Irupte" Aro-ch REC_LOCKER(0) o && try ornv antil iruptE"RtryFXxeTi-erUntil Irupte" Aro-ch REC_LOCKER(2) o&& try2seds rntil iruptE
ReslvsA FaileLok: I7sue ofR-spons
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mamenun 2U)char-cod a-sisl hoic-,o-multiplchoic-sbasomconditallogic If vid multiplchoic-s,E coffcN[tem o on a viaa Cnura--thar-codEtm. Npariula--respons nsacrosanct. Wat)naroprian deends ealicatyua tass.2UWatev--hoic- mak,do -negnn o UNLOCK a7soasT:possn afyua lokha asevdis pur If --responsivlvesa Cnu, UNLOCK beforn displayt. O wi
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REPORT FORM o o o SORT...TO ...
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c-du. Act,-iformat.n Ralworlsanpc-dus ares'tquitsoidal.n Fs ccoacode tat)donsssaar- m demisEtvalun oretur Pc-dus mightassignvalunsopublicEvarinnsusindictlyreturiformat o tcalr. Butin--al,sareon fulfriformat yprovde&ilpc-dusareon fulfrsstydo.n Sowdonsal i7leavRLOCK() aFLOCK()? Wll,Xrst oEal y'r s Just lookat) paress Ty!returlogiiformatabutcurNreordor Xnn IfEtyretur"ru"i'sloked,if "fals"ii7s't TisisEiprtaiformat. Wn-eit &nvr whavimienEpaonttat)requisprivacntrol ofdata. Won )iformat o decid & ti'ssafn ogoahead& N Epaon. RLOCK() aFLOCK()are a qurystools. Exampl:2Uo RLOCK() asa-fu2Uo IF RLOCK()2Uo 2Uo ELSE2Uo <-safn odo so -w,gveon a a Cssagnsad>2Uo ENDIF2UBut)sshavseond,lss visn role Ty EloksgensdhdBASElanguag Tyr( taplylokEeac)i-e tyexecuted Tisispc-du-lik,aicontrastEto -lik rolepformeabv. Wha's-apparEabvisat)RLOCK() tselfrinsoseiznhreordaonlyEtreprtsstatus. Sovnif hreordwcN'lokedgosinto IF statC,RLOCK() mightst returru,n beaon it could cSan/hreordfm unloked)t loked)duisits ownpaon. Ifatre's- wa( t k-w)lokstatusn befornIF statC (unlss whavkeptrackof hresultsEfpnvious lokstvty) O a only caidatool frEfis out isRLOCK() But)i'sdisqualifiedbeaon itiflunnc-sstatusdhpc-ss fevaluas it. LikHeisenberg unceraty in physics, Casua disturbs ECasud,maksCasuCimpossn Tisis'a-pm.I'san-wcircumstasceat)just tak-sa-littnnges on d o.n 2Uloop-below demstas pc-du-lik aspt fRLOCK()'sdualpsonalty:2Uo RLOCK() asa-pc-du2Uo DO WHILE .NOT.RLOCK()2Uo ENDDOn 2UAtXrst glasceit lookslik tre'scode misssfm & NieEloop,asin:2Uo DO WHILE .NOT.EOF() nsad f DO WHILE .NOT.EOF()2Uo ENDDOo o o SKIP2Uo ENDDOn 2UBut)a's-tcasn. RLOCK() sdiffcNfm EOF(). EOF()2Un pure. It only te l a if areraN'atEenffXnn,but)idons'atvlydo yths abuit TatEwhySKIP snssary. W Nouit)loop-goesfornvr beaon Eti7-hsto cSan/hstatusfEOF().2UBycntrast,RLOCK() s'a-pure. It atvlyrinsoEloktcurNreordnvry)i-e trough tloop If o Eworksatdeniesitsucc-ss by holdssreordloked,itEkeepsloops. But)no soor)donse o tworksatUNLOCKtEreordanRLOCK(), pc-du,geshreordloked,sohatERLOCK(), ,retursru. At)aitloop-isEexitedapc-sss ccoinu. So,tough -tbestE)mstechniqu,)RLOCK() loop-abvmak-ssensn. IsaysE"waitunlhreordcblokedfm i7worksat,)n
c-ed" RLOCK() pformsav roleoa-pc-du,likSKIP,asw as passiveoa-fu,lik EOF().2UTfamiliarizn aselffur tw NRLOCK() aFLOCK(),lookatEtcode inhLOCK