ыOU CAN DO IT ON THE SCREEN, HOW ABOUT BORDERS ? бECAUSE YOU CANNOT GET CHARACTERS TO THE BORDER, YOU MIGHT THINK THAT IT IS IMPOSSIBLE TO MAKE A TECH-TECH EFFECT IN THE BORDERS. иT TAKES SO MUCH TIME TO CHANGE SPRITE X-COORDINATES, THAT YOU CAN CHANGE ONLY SOME OF THEM. тHERE IS TIME FOR FIVE SPRITE MOVES, IF YOU DO NOT NEED TO CHANGE THE MOST SIGNIFICANT (9TH) BIT OF THE X-COORDINATE. оN THE OTHER HAND, YOU COULD DESIGN THE MOVEMENTS DIRECTLY TO THE SPRITES AND THEN JUST CHANGE THE IMAGES, BUT THEN THE MOVEMENTS WOULD BE CONSTANT. хOWEVER, THERE IS ONE TRICK YOU CAN USE TO GET ALL OF THE SPRITES ON THE SCREEN, WITH VARIABLE MOVEMENTS AND COLOR BARS ETC. ыOU DO NOT CHANGE THE X-COORDINATES, BUT THE DATA ITSELF ON EACH SCAN LINE. иN FACT YOU CHANGE THE SPRITE IMAGE POINTERS. тHERE IS MULTIPLE SPRITE PICTURES, WHERE THE GRAPHICS IS SHIFTED HORIZONTALLY, JUST LIKE THE NORMAL TECH-TECH CHARSETS. бECAUSE OF THIS, THE SPRITES HAVE TO BE PLACED SIDE BY SIDE. нO GAPS ARE ALLOWED. бY CHANGING THE IMAGE POINTERS YOU CAN GET THE GRAPHICS TO MOVE HORIZONTALLY ON EACH LINE AS YOU WISH. вITH MULTICOLOR SPRITES YOU HAVE TO REMEMBER THAT ONE PIXEL CORRESPONDS TO TWO BITS - THE MOVEMENT IS NOT SO SMOOTH. вAIT ! хOW COME THERE IS ENOUGH TIME TO CHANGE THE SPRITE POINTERS, WHEN THERE IS NOT TIME TO CHANGE THE COORDINATES ? тHIS IS ANOTHER POINTER TRICK. жиц READS THE SPRITE IMAGE POINTERS FROM THE END OF THE CURRENT VIDEO MATRIX, NORMALLY $07F8. ыOU JUST HAVE TO CHANGE THE VIDEO MATRIX POINTER ($д018) TO CHANGE ALL OF THE IMAGE POINTERS. тHIS TAKES ONLY EIGHT CYCLES AND THERE IS PLENTY OF TIME LEFT FOR OTHER EFFECTS ON EACH SCAN LINE. иF YOU USE ONLY ONE VIDEO BANK, YOU CAN GET THE SPRITE PICTURE TO 16 DIFFERENT PLACES. тHIS ALLOWS ALSO ANOTHER KIND OF EFFECTS, JUST USE YOUR IMAGINATION. -------------------------------------------------------------------------- тECH-TECH DEMO PROGRAM (пал) банк= $96 ; тHE VALUE OF THE VIDEO BANK REGISTER (циа2) IN THE TECH-AREA зп= $фб ; зERO PAGE FOR INDIRECT ADDRESSING старт= $4400 ; сTART OF THE CHARSETS (WE USE INVERTED CHARS) сцреен= $4000 ; пOSITION OF THE VIDEO MATRIX схифтл= $цф00 ; X-SHIFT, LOWEST 3 BITS схифтх= $це00 ; X-SHIFT, HIGHEST 3 BITTID (MULTIPLIED WITH TWO) поинтер= $033ц ; пOINTER TO SHIFT-TABLE жалуе= $033д ; сHIFT NOW спеед= $033е ; сHIFT CHANGE *= $ц000 ; сTART ADDRESS.. инит сеи ; дISABLE INTERRUPTS лда #$7ф ста $дц0д ; дISABLE TIMER INTERRUPT лда #$81 ста $д01а ; еNABLE RASTER INTERRUPT лда #<иря ста $0314 ; оUR OWN INTERRUPT HANDLER лда #>иря ста $0315 лда #49 ; тHE INTERRUPT TO THE LINE BEFORE THE FIRST BAD LINE ста $д012 лда #$1б ста $д011 ; 9TH BIT OF THE RASTER COMPARE лды #0 лдь #$40 сть зп+1 сты зп тыа лооп0 ста (зп),ы ; цLEAR THE WHOLE VIDEO BANK ($4000-7ффф) ины бне лооп0 инц зп+1 бпл лооп0 лда #>старт ста зп+1 лда #$32 ; цHARACTER ром TO ADDRESS SPACE ($д000-) ста $01 лооп1 тыа ; (ы-REGISTER IS ZERO INITIALLY) лср лср лср таь лда теьт,ь ; вHICH CHAR TO PLOT ? асл ; сOURCE асл асл таь ; LOW BYTE TO ь лда #$д0 адц #0 ; HIGH BYTE (ONE BIT) TAKEN INTO ACCOUNT ста лооп2+2 ; сELF-MODIFYING AGAIN.. лооп2 лда $д000,ь ста (зп),ы инь ины тьа анд #7 бне лооп2 ; цOPY ONE CHAR цпы #0 бне лооп1 ; цOPY 32 CHARS (256 BYTES) лда #$37 ; мEMORY CONFIGURATION BACK TO NORMAL ста $01 лооп3 лда старт,ы ; цOPY THE DATA TO EACH CHARSET, SHIFTED BY ONE ста старт+2056,ы ; POSITION TO THE RIGHT ста старт+4112,ы ста старт+6168,ы ста старт+8224,ы ста старт+10280,ы ста старт+12336,ы ста старт+14392,ы ины бне лооп3 лда #0 ; цLEAR THE POINTER, VALUE AND SPEED ста поинтер ста жалуе ста спеед лооп4 тыа ; (ы WAS ZERO) ора #$80 ; уSE THE INVERTED CHARS ста сцреен,ы ; сET THE CHARACTER CODES TO VIDEO MATRIX ста сцреен+40,ы ста сцреен+80,ы ста сцреен+120,ы ста сцреен+160,ы ста сцреен+200,ы ста сцреен+240,ы ста сцреен+280,ы лда #239 ; LEAVE THE LAST LINE EMPTY ста сцреен+320,ы ины цпы #40 бне лооп4 ; лOOP UNTIL THE WHOLE AREA IS FILLED цли ; еNABLE INTERRUPTS ртс иря лда #банк ; цHANGE THE VIDEO BANK, SOME TIMING ста $дд00 ноп ноп лды поинтер ; ы-REGISTER WILL POINT TO X-SHIFT ймп бад ; NEXT LINE IS A BAD LINE лооп5 ноп лооп6 лда схифтл,ы ; дO THE SHIFT ста $д016 ; 3 LOWEST BITS лда схифтх,ы ста $д018 ; ANOTHER 3 BITS ноп : ноп : ноп : ноп : ноп : ноп ; WASTE SOME TIME ноп : ноп : ноп : ноп : ноп : ноп ноп : ноп : ноп лда $д012 ; CHECK IF IT IS TIME TO STOP цмп #$78 бпл ожер ины ; NEXT POSITION IN TABLE деь бне лооп5 ; нO BAD LINE, LOOP бад лда схифтл,ы ; тHIS IS A BAD LINE, A BIT MORE HURRY ста $д016 лда схифтх,ы ста $д018 ины лдь #7 ; нEW BAD LINE COMING UP ймп лооп6 ожер лда #$97 ; жIDEO BANK TO 'NORMAL' ста $дд00 лда #22 ; сAME WITH THE CHARSET ста $д018 лда #8 ; AND THE HORIZONTAL SCROLL REGISTER ста $д016 лда $дц00 ; лET'S CHECK THE JOYSTICKS анд $дц01 таь лды спеед анд #8 ; тURNED RIGHT, ADD SPEED бне еип ины цпы #4 ; дON'T STORE, TOO MUCH SPEED бпл еип сты спеед еип тьа анд #4 ; тURNED LEFT бне улос деы цпы #$фц ; тOO MUCH ? бми улос сты спеед улос лда жалуе ; аDD SPEED TO VALUE (SIGNED) цлц адц спеед бпл ок лда спеед ; бANGED TO THE SIDE ? еор #$фф цлц адц #1 ста спеед лда жалуе ок ста жалуе лср ; жALUE IS TWICE THE SHIFT таь ; рEMEMBER THE SHIFT анд #7 ; LOWEST 3 BITS ора #8 ; (SCREEN 40 CHARS WIDE) лды поинтер ста схифтл,ы тьа лср лср лср ; HIGHEST 3 BITS TOO асл ; MULTIPLICATED BY TWO ста схифтх,ы дец поинтер лда #1 ; аCK THE INTERRUPT ста $д019 ймп $еа31 ; тHE NORMAL INTERRUPT ROUTINE теьт сцр "тхис ис тецх-тецх фор ц=64 бы ме" ; тEST TEXT ; сцр CONVERTS TO SCREEN CODES -------------------------------------------------------------------------- бASIC LOADER FOR THE тECH-TECH DEMO PROGRAM (пал) 1 с=49152 2 деффнх(ц)=ц-48+7*(ц>64) 3 цх=0:реада$,а:принта$:ифа$="енд"тхенпринт"":сыс49152:енд 4 форф=0то31:я=фнх(асц(мид$(а$,ф*2+1)))*16+фнх(асц(мид$(а$,ф*2+2))) 5 цх=цх+я:покес,я:с=с+1:неьт:ифцх=атхен3 6 принт"цхецксум еррор":енд 100 дата 78а97ф8д0ддца9818д1ад0а9ад8д1403а9ц08д1503а9318д12д0а91б8д11д0а0, 3802 101 дата 00а24086фц84фб9891фбц8д0фбе6фц10ф7а94485фца9328501984а4а4ааабд5е, 4749 102 дата ц10а0а0аааа9д069008д4ец0бд00д091фбе8ц88а2907д0ф4ц000д0дда9378501, 4128 103 дата б9004499084ц99105499185ц99206499286ц99307499387цц8д0е5а9008д3ц03, 3258 104 дата 8д3д038д3е0398098099004099284099504099784099а04099ц84099ф0409918, 3236 105 дата 41а9еф994041ц8ц028д0дб5860а9968д00ддеаеаац3ц034це1ц0еаб900цф8д16, 4464 106 дата д0б900це8д18д0еаеаеаеаеаеаеаеаеаеаеаеаеаеаеаад12д0ц9781016ц8цад0, 5850 107 дата д9б900цф8д16д0б900це8д18д0ц8а2074цббц0а9978д00дда9168д18д0а9088д, 4132 108 дата 16д0ад00дц2д01дцааац3е032908д008ц8ц00410038ц3е038а2904д00888ц0фц, 3160 109 дата 30038ц3е03ад3д03186д3е03100еад3е0349фф1869018д3е03ад3д038д3д034а, 2139 110 дата аа29070908ац3ц039900цф8а4а4а4а0а9900цеце3ц03а9018д19д04ц31еа1408, 2759 111 дата 091320091320140503082д1405030820060ф1220033д3634200219200д050ф12, 652 200 дата енд,0 -------------------------------------------------------------------------- уUENCODED ц64 EXECUTABLE VERSION OF THE DEMO PROGRAM (пал) BEGIN 644 TECH.64 мю0@-"ю$ю4[(т.3$у,@юф"ю(юей5(*$,илд.к-#бй-зпх0[$ж-"дю7ю@#ю$-(й млцюзат$д+$$зф4$д.хм!)+(б14ы$(й>9(цс7р,г4я3ь\п\с2/б(згц0ы,34р; м.хююдп@$ю(%&лц"д,с$з4;*е2"ц&*,хх020л1йпрйц$и*2фл,3:йи4@хябц*1 м*$$д+$:л,йхр*2дию+0(!0!#2+)#2*и1.и=3+%$з4[)3йц$з@цй+0тбр0:<с? мю,п(!@"9(д-(14-+4у5-($524д]2(цйюю!д)9ю"#(#<ь03дв1ца$,$1$0т$ын м.#$ь1#%!1#!!.4%$.$0я-#юс03е#,#а$,34п,т$ы,с$ь1#$р1#!!.3%".$0я+ м,40п03юл(#,ь,#(ю9@еею(,@,#!!,ц0п.#9&0с@т1д(ы.#дя1д)#.$0п1д)%г м-д9#,3!&-т$ы-#0ь-49#03дс,ц@у,#$ы.#1!-$$т04%!0д0у12п@-#<т.0"с+ м"68ю@р!#,3!!,$$п04%!03е$,#8ы,#юь1#1%0с!"1#юп1#юы,49"13а#.#а!] м,цдп-т0п1ц1#,#юп1#!$1$$ы,с<ь-3юя+"ют,3(ьююю*9п"#($(ы,#ют-#дые м,#@т0сды,3юу-#ды,3@у0сды,цюж-#ды,ц@ж0сды,сюв-#ды,с@в0т,ь1#!%, м-4$ы,#юь1#-#,#,л(#,р-3@ю30ихю(,@.$0с1#юс.$0с13юс.3@п.3@п.3дпу м,#0п.3др.#0п.3ду,#0п.3дв.#0п.3е!,#0п.3е#.#0п.3е&,#0п.3дя."п@? м,с(с-@":"фдю@рют,4$ы148ы.30п-#%#.$,п,ца$,$1"-3@ж,$$ы.38ь1#юп- м1$1%045!04,с0сюс-$-%,4,п14%".3юп0т8ь1#$ж+"ют-#8тю.<*:@"#($0пн м0цдп,$-%.$0я.$0п14%%045!14%%045!14%%045!14%%045!14%%045!040я, м,д0п0сдв.#$п,39#.$-!1#юл(#4ь-3юю-юмкю(,@1#е".3юп0т8ь1#$ж1#!"я м.3юп0т4ь1#$ь1#!#.$$р,#<т0т)"0с!!.3дв.$0п,$1$03дя-ца$,3а$,$$ы_ м,#@ь1"п@-#$с,@"!"жпю@рюя-д0п040п,$1#,д0п,41#04%!0с-%,#,р.3юьн м1#юп.$,ь0сюп-#$п,#,ь0с-%,#,ь03(ы,#1$,#юь.#а#,$9#+"юс,38пю,ь+' м;0"#(#,п,#,ь0с-%,#-!1#-$,#,я.#9$,т4п,с$п,$5!1#-%,#,т.49&,3@ж7 м.3юя.$0с13юс040с1#юс.$0с1#юс-$$л(#(я,сдю&пяню(,@04$р.3юв,#дп; м.$%#,т,п,сды,#!#1ца!-$$т031!,$$ы.3юп0т5#13-#,#-!.3юя.$0я.40пи м-$,с,45!,30п."п@,ц<у.0!г#&\ю@рюп.3$с,цюп.3$с,цюя-#юу,#,п.#)$_ м,30п-3юс,#@р,#юж,$8я,ц(п,#,с1#,ж,с0р,#юр,3др,#!$,#4п1ц$р+"юж& 4-3(ю<пс(ю(,@14ы$+#ююююююююхс! юю END ============================================================================= аце-128/64 программер'с референце гуиде (VERSION 0.9, FOR рELEASE #10) BY цRAIG бRUCE 1. интродуцтион аце IS A PROGRAM FOR THE цOMMODORE 128 AND цOMMODORE 64 THAT PROVIDES A COMMAND SHELL ENVIRONMENT THAT IS SIMILAR TO THAT OF уNIX. иT IS STILL IN THE DEVELOPMENT STAGE, BUT ENOUGH OF IT IS COMPLETE TO BE USEFUL. бтв, "аце" MEANS "аDVANCED цOMPUTING еNVIRONMENT" (WELL, ADVANCED FOR THE 128/64). сO WHAT IS аце ALL ABOUT? вELL, ORIGINALLY и TRIED A VERY AMBITIOUS PROJECT OF WRITING A MULTITASKING OPERATING SYSTEM FOR THE 128. иT GOT IT PARTIALLY WORKING, BUT IT WAS MUCH TOO FRAGILE AND INCOMPLETE TO BE RELEASED. иT WAS A WHITE-ELEPHANT PROJECT. сO, THEN THEN IT CAME TO ME THAT и WAS AIMING MUCH TOO HIGH. вHAT и NEEDED WAS A MUCH SIMPLER SYSTEM, ONE THAT WOULD GIVE THE TYPE OF PROGRAMMING INTERFACE AND BUILT-IN FEATURES THAT и WANTED, BUT ONE THAT WAS CLOSE ENOUGH TO THE цOMMODORE кERNAL THAT IT WOULD NOT REQUIRE MUCH OF A PROGRAMMING EFFORT TO HACK TOGETHER A MINIMAL IMPLEMENTATION. аND THUS, THERE WAS аце-128 рELEASE #1. аND и SAW IT WAS GOOD. вHAT и WANTED WAS A SYSTEM THAT WOULD BE EASIER TO PROGRAM THAN THE цOMMODORE кERNAL WITH ALL ITS WEIRD AND WONDERFUL DEVICE TYPES, NON-EXISTENT MEMORY MANAGEMENT, AND SINGLE-APPLICATION DESIGN. тHE FIRST IMPORTANT FEATURE OF THIS ENVIRONMENT WAS TO BE ABLE TO PASS ARGUMENTS FROM A COMMAND LINE TO AN APPLICATION PROGRAM BY TYPING THEM ON THE COMMAND LINE OF THE SHELL. иT IS SO ANNOYING TO LOAD UP A PROGRAM IN басиц, RUN IT, AND HAVE IT ASK YOU FOR FILENAMES IN SOME HIGHLY INCONVENIENT WAY. аNOTHER IMPORTANT SYSTEM FEATURE IS TO MAKE NEAR AND FAR MEMORY MANAGEMENT PART OF THE SYSTEM, AND TO MAKE FAR MEMORY CONVENIENT TO USE FOR STORING MASSIVELY BULKY DATA. аND SO IT WAS. аLSO, WE WANT TO USE CUSTOM DEVICE DRIVERS. цOMMODORE DIDN'T REALLY COME THROUGH WITH THE DEVICE DRIVERS IT PROVIDED. тHEY ARE ALL реаллы слов. аND SO THAT WAS, ALSO, ALTHOUGH MORE CUSTOM DEVICE DRIVERS ARE NEEDED. вE WANT TO HAVE THE CAPABILITY OF MAKING PROGRAMS WORK TOGETHER, RATHER THAN HAVING PROGRAMS THAT ARE TOTALLY INCOMPATIBLE. тHIS FUNCTIONALITY IS STILL UNDER CONSTRUCTION. пROGRAMS WILL WORK TOGETHER IN THIS UNI-TASKING ENVIRONMENT BY ALLOWING A PROGRAM TO EXECUTE ANOTHER PROGRAM AS A SUB-TASK, AND THEN HAVING CONTROL RETURN TO THE CALLING PROGRAM UPON EXIT. фINALLY, WE WANT SOME GOOD QUALITY APPLICATIONS AND A POWERFUL COMMAND SHELL. тHIS IS STILL BEING WORKED ON AND PROGRESS IS COMING SLOWLY. оH, ALMOST FORGOT; WE ALSO WANT ALL PROGRAMS TO WORK ON BOTH THE ц64 AND ц128, AND THEY DO. тHIS DOCUMENTATION REFERS TO аце RELEASE #10, WHICH HAS NOT BEEN RELEASED YET (OR EVEN PROGRAMMED). иN FACT, THE CURRENT RELEASE IS #9. рELEASE #10 WILL BE SPRUCED UP FROM THE INSIDE OUT TO SUPPORT THE SYSTEM INTERFACE DESCRIBED IN THIS DOCUMENT. тHE CURRENT RELEASE IS NOT BEING DESCRIBED, BECAUSE SOME OF ITS FEATURES ARE NOT THE BEST THEY COULD POSSIBLY BE. нOTE, HOWEVER, THAT THE BASIC FEATURES, LIKE "OPEN", "READ", "DIRREAD", AND ARGV ARE NOT GOING TO CHANGE. нOTE ALSO THAT THE VERSION NUMBER OF THIS "п.р.г." IS 0.9. тHIS IS BECAUSE THIS IS THE FIRST INCARNATION OF THIS DOCUMENT AND, CONSIDERING ITS NATURE, IS BOUND TO HOLD A LARGE NUMBER OF SMALL ERRORS. 2. сыстем интерфаце тHIS SECTION DESCRIBES THE INTERFACE BETWEEN USER PROGRAMS AND THE аце KERNEL. и AM VERY CAREFUL THROUGHOUT THIS INTERFACE SPECIFICATION ABOUT REVEALING ANY INTERNAL DETAILS THAT YOU DO NOT STRICTLY NEED TO KNOW. тHE INTERFACE WITH аце IS NOT SPECIFIED IN TERMS OF ABSOLUTE ADDRESSES; TO AID IN PORTABILITY AND EXTENSIBILITY, ALL INTERFACES ARE SPECIFIED IN TERMS OF SYMBOLIC ASSEMBLER LABELS. аLL OF THE аце CODE IS CURRENTLY WRITTEN FOR THE бUDDY-128 ASSEMBLER. аLSO, BECAUSE THESE INTERFACE ABSOLUTE ADDRESSES ARE SUBJECT TO CHANGE FROM VERSION TO VERSION OF THE KERNEL, EXECUTABLES COMPILED FOR USE WITH AN OLD VERSION OF аце MAY NOT WORK WITH A NEW VERSION. 2.1. зеро-паге жариаблес тHERE ARE FOUR ZERO-PAGE VARIABLES USED FOR PASSING ARGUMENTS IN MOST SYSTEM CALLS. тHEY ARE AS FOLLOWS: сымбол бытес десцриптион ------- ----- ----------- ZP 2 ZEROPAGE POINTER ZW 2 ZEROPAGE WORD MP 4 MEMORY POINTER SYSWORK 16 SYSTEM WORK AREA / ARGUMENTS тHE FIRST TWO, "ZP" AND "ZW" ARE USED IN MOST CALLS. тHEY STORE SIMPLE 16-BIT VALUES; "ZP" USUALLY STORES POINTERS TO STRINGS IN рам0 MEMORY. тHE "MP" VARIABLE IS 32-BITS IN LENGTH AND IS USED EXCLUSIVELY FOR PASSING FAR MEMORY POINTERS FOR USE WITH THE FAR MEMORY ROUTINES. аLL THREE OF THESE VARIABLES WILL REMAIN UNCHANGED INSIDE OF SYSTEM CALL UNLESS THEY WILL CONTAIN A RETURN VALUE. "SYSWORK" IS A 16-BYTE ARRAY USED MAINLY WHEN THERE ARE TOO MANY ARGUMENTS FOR OTHER VARIABLES TO HOLD, AND ALL NON-INPUT AND NON-OUTPUT BYTES OF "SYSWORK" ARE SUBJECT TO CHANGE BY THE KERNEL. аLL INPUT ARGUMENTS PLACED IN THE "SYSWORK" LOCATIONS WILL BE PRESERVED UNLESS OTHERWISE INDICATED. [нOTE: иN рELEASE #9, "ZP" TOOK ON THE ROLLS OF BOTH "ZP" AND "MP"]. 2.2. сыстем жариаблес тHERE ARE SEVERAL NON-ZEROPAGE VARIABLES FOR STORING SYSTEM STATUS AND RETURN VALUES: сымбол бытес десцриптион ---------- ----- ----------- ERRNO 1 ERROR NUMBER CODE RETURNED BY FAILED SYSTEM CALLS ACEид 2 PROOF THAT USER PROGRAM IS RUNNING ON TOP OF аце ACEаRGC 2 ARGUMENT COUNT FOR CURRENT PROCESS ACEаRGV 2 ARGUMENT VECTOR ADDRESS FOR CURRENT PROCESS ACEмEMтOP 2 HIGHEST ADDRESS, PLUS ONE, THAT USER PROG CAN USE ACEсHELLпATH 2 PTR TO STORAGE FOR SEARCH PATH FOR EXECUTABLE PROGRAMS ACEсHELLаLIAS 2 PTR TO STORAGE FOR SHELL COMMAND ALIASES ACEцURдIRнAME 2 PTR TO STORAGE FOR THE CURRENT DIRECTORY NAME ACEеXITдATA 2 PTR TO STORAGE FOR EXIT STATUS FROM THE LAST CALLED PRG ACEдIRENTбUFFER STORAGE FOR DIRECTORY ENTRIES READ FROM DISK ACEдIRENTлENGTH - REALLY A CONSTANT: LENGTH IN BYTES OF "ACEдIRENTбUFFER" ACEдIRENTбYTES 4 BYTES IN FILE (USUALLY INEXACT) ACEдIRENTдATE 8 DATE OF FILE IN "ыы:ыы:мм:дд:хх:мм:сс:тв" FORMAT ACEдIRENTтYPE 4 TYPE OF FILE IN NULL-TERMINATED STRING ACEдIRENTфLAGS 1 FLAGS OF FILE, "DRWX*-ET" FORMAT ACEдIRENTнAMEлEN 1 LENGTH OF NAME OF FILE ACEдIRENTнAME 17 NULL-TERMINATED NAME OF FILE еррно: "ERRNO" IS USED TO RETURN ERROR CODES FROM SYSTEM CALLS. вHEN A SYSTEM CALL ENDS IN ERROR, IT SETS THE CARRY FLAG TO "1", PUTS THE ERROR CODE IN "ERRNO", AND RETURNS TO THE USER PROGRAM, AFTER UNDOING ANY SYSTEM WORK COMPLETED AT THE TIME THE ERROR IS ENCOUNTERED AND ABORTING THE OPERATION. аN ERROR CODE NUMBER IS STORED IN BINARY IN THE SINGLE-BYTE "ERRNO" LOCATION. тHE SYMBOLIC NAMES FOR THE POSSIBLE ERROR CODES ARE GIVEN IN THE NEXT SECTION. иF NO ERROR OCCURS IN A SYSTEM CALL, THE CARRY FLAG WILL BE CLEARED ON RETURN FROM THE CALL. нOTE THAT NOT ALL SYSTEM CALLS CAN RUN INTO ERRORS, SO NOT ALL SET THE CARRY FLAG ACCORDINGLY. ид: "ACEид" IS A TWO-BYTE VARIABLE. иTS PURPOSE IS TO ALLOW USER PROGRAMS TO BE SURE THAT THEY ARE EXECUTING ON TOP OF аце. тHE LOW BYTE (I.E., THE FIRST BYTE) MUST BE EQUAL TO THE SYMBOLIC CONSTANT "ACEид1", AND THE HIGH, "ACEид2". тHIS WILL ALLOW аце APPLICATIONS TO INFORM IDIOT USERS THAT THEY CANNOT SIMPLY боот THE PROGRAM FROM басиц, BUT RATHER THEY MUST RUN аце FIRST. аргц: "ACEаRGC" IS A TWO-BYTE UNSIGNED NUMBER. иT GIVES THE NUMBER OF ARGUMENTS PASSED TO THE APPLICATION BY THE PROGRAM (USUALLY THE COMMAND SHELL) THAT CALLED THE APPLICATION. тHE FIRST ARGUMENT IS ALWAYS THE NAME OF THE APPLICATION PROGRAM, SO THE COUNT WILL ALWAYS BE AT LEAST ONE. оTHER ARGUMENTS ARE OPTIONAL. аргж: "ACEаRGV" IS A TWO-BYTE рам0 POINTER. пAY ATTENTION. тHIS POINTER POINTS TO THE FIRST ENTRY OF AN ARRAY OF TWO-BYTE POINTERS WHICH POINT TO THE NULL-TERMINATED STRINGS THAT ARE THE ARGUMENTS PASSED TO THE APPLICATION PROGRAM BY THE CALLER. (а NULL-TERMINATED STRING IS ONE THAT ENDS WITH A ZERO BYTE). тO FIND THE ADDRESS OF THE н-TH ARGUMENT TO AN APPLICATION, MULTIPLY н BY TWO, ADD THE "ACEаRGV" CONTENTS TO THAT, AND FETCH THE POINTER FROM THAT ADDRESS. иN THIS SCHEME, THE EVER-PRESENT APPLICATION NAME IS THE 0-TH ARGUMENT. тHE ARGV[ARGC] ELEMENT OF THE ARGUMENT VECTOR WILL ALWAYS CONTAIN A VALUE OF $0000, A NULL POINTER. мем-топ: "ACEмEMтOP" IS A TWO-BYTE рам0 POINTER. тHIS POINTS TO ONE BYTE PAST THE HIGHEST BYTE THAT THE APPLICATION PROGRAM IS ALLOWED TO USE. аLL APPLICATION PROGRAMS ARE LOADED INTO MEMORY AT ADDRESS "ACEаPPаDDRESS" (NEXT SECTION), AND ALL MEMORY BETWEEN THE END OF THE PROGAM CODE AND "ACEмEMтOP" CAN BE USED FOR TEMPORARY VARIABLES, FILE BUFFERS, ETC. тHE MAIN PROBLEM WITH THIS APPROACH IS THAT THERE ARE NO GUARANTEES ABOUT HOW MUCH MEMORY YOUR APPLICATION WILL GET TO PLAY WITH. мANY APPLICATIONS, SUCH AS SIMPLE FILE UTILITIES, CAN SIMPLY USE ALL AVAILABLE MEMORY FOR A FILE BUFFER, BUT OTHER PROGRAMS, SUCH AS A FILE COMPRESSOR, MAY HAVE MUCH GREATER DEMAND FOR "NEAR" MEMORY. [нOTE: THIS VARIABLE HAS A DIFFERENT NAME IN рELEASE #9]. схелл-патх: "ACEсHELLпATH" IS A TWO-BYTE рам0 POINTER. тHIS POINTS TO THE PAGE OF MEMORY THAT STORES THE PATHNAMES OF DIRECTORIES TO SEARCH THROUGH IN ORDER TO FIND EXECUTABLE FILES. еACH PATHNAME IS STORED AS A NULL-TERMINATED STRING, AND THE LIST IS TERMINATED BY AN EMPTY STRING (CONTAINING ONLY THE ZERO CHARACTER). тHIS IS INTENDED TO BE USED BY THE SHELL PROGRAM, OR ANY OTHER PROGRAM THAT IS SO INCLINED, TO EXAMINE OR ALTER THE SEARCH PATH. тHE SEARCH PATHS SPECIFIED IN THE PATH PAGE ARE GLOBAL VARIABLES AND ARE USED BY ALL PROGRAMS THAT MAKE THE "EXEC" SYSTEM CALL. тHIS MECHANISM FOR READING/ALTERING THE EXECUTABLE SEARCH PATH MAY BE CHANGED IN THE FUTURE. схелл-алиас: "ACEсHELLаLIAS" IS A TWO-BYTE рам0 POINTER. тHIS POINTS TO THE PAGE OF MEMORY THAT STORES THE ALIASES TO BE USED WITH THE COMMAND SHELL. аN ALIAS IS A STRING THAT IS SUBSTITUTED IN THE PLACE OF A COMMAND NAME ON A SHELL COMMAND LINE WHENEVER A CERTAIN COMMAND NAME COMES UP. фOR EXAMPLE, YOU MIGHT SPECIFY IF THE USER ENTERS THE COMMAND "LIST A:" THAT THE COMMAND NAME "LIST" BE STRING-REPLACED WITH "CLS;XLS -L". еACH ALIAS IS STORED WITH THE COMMAND NAME FIRST, FOLLOWED BY AN EQUALS CHARACTER ("="), FOLLOWED BY THE STRING TO SUBSTITUTE, FOLLOWED BY A ZERO. тHE ALIAS LIST IS TERMINATED BY AN EMPTY STRING. тHIS MECHANISM MAY BE EXTENDED IN THE FUTURE TO ALLOW MULTIPLE PAGES OF ALIASES, OR MAY BE CHANGED COMPLETELY. цур-дир-наме: "ACEцURдIRнAME" IS A TWO-BYTE рам0 POINTER. иT POINTS TO THE NULL-TERMINATED STRING INDICATING THE CURRENT DIRECTORY. тHE USER IS NOT SUPPOSED TO MODIFY THIS VALUE, AND THE VALUE WILL NOT ALWAYS GIVE A FULL PATHNAME. тHE IMPLEMENTATION OF THIS FEATURE MAY NEED TO CHANGE IN FUTURE VERSIONS OF аце. аце-еьит-дата: "ACEеXITдATA" IS A TWO-BYTE рам0 POINTER. иT POINTS TO THE 256-BYTE BUFFER ALLOCATED FOR USER PROGRAMS TO GIVE DETAILED RETURN INFORMATION UPON EXITING BACK TO THEIR PARENT PROGRAM. сEE THE "EXIT" SYSTEM CALL. уSER PROGRAMS ARE ALLOWED TO READ AND WRITE THIS STORAGE. аN EXAMPLE USE OF THIS FEATURE WOULD BE A COMPILER PROGRAM RETURNING THE LINE NUMBER AND CHARACTER POSITION, AND DESCRIPTION OF A COMPILATION ERROR TO A TEXT EDITOR, SO THE EDITOR CAN POSITION THE CURSOR AND DISPLAY THE ERROR MESSAGE FOR USER CONVENIENCE. тHE IMPLEMENTATION OF THIS FEATURE MAY NEED TO CHANGE IN FUTURE VERSIONS OF аце. дирент-буффер: "ACEдIRENTбUFFER" IS A BUFFER USED FOR STORING DIRECTORY INFORMATION READ WITH THE "DIRREAD" SYSTEM CALL, AND IS "ACEдIRENTлENGTH" BYTES LONG. оNLY A SINGLE DIRECTORY ENTRY IS (LOGICALLY) READ FROM DISK AT A TIME. тHE INDIVIDUAL FIELDS OF A READ DIRECTORY ENTRY ARE ACCESSED BY THE FIELDS DESCRIBED NEXT. тHIS FIELD IS ALSO USED FOR RETURNING DISK NAME INFORMATION AND THE NUMBER OF BYTES FREE ON A DISK DRIVE (SEE THE "DIRREAD" SYSTEM CALL). дирент-бытес: "ACEдIRENTбYTES" IS A FOUR-BYTE (32-BIT) UNSIGNED FIELD. аS ALWAYS, THE BYTES ARE ADDRESSED FROM LEAST SIGNIFICANT TO MOST SIGNIFICANT. тHIS FIELD GIVES THE NUMBER OF BYTES IN THE FILE. нOTE THAT THIS VALUE MAY NOT BE EXACT, SINCE цOMMODORE DECIDED TO STORE SIZES IN DISK BLOCKS RATHER THAN BYTES. фOR DEVICES THAT REPORT ONLY BLOCK COUNTS (I.E., EVERY DISK DEVICE CURRENTLY SUPPORTED), THE NUMBER OF BYTES RETURNED IS THE NUMBER OF BLOCKS MULTIPLIED BY 254. тHIS FIELD, AS WELL AND THE OTHER DIRENT FIELDS ARE ABSOLUTE ADDRESSES, NOT OFFSETS FROM ACEдIRENTбUFFER. дирент-дате: "ACEдIRENTдATE" IS AN EIGHT-BYTE ARRAY OF BINARY CODED DECIMAL VALUES, STORED FROM MOST SIGNIFICANT DIGITS TO LEAST SIGNIFICANT. тHE FIRST BYTE CONTAINS THE бцд CENTURY, THE SECOND THE YEAR, AND SO ON, AND THE LAST BYTE CONTAINS THE NUMBER OF TENTHS OF SECONDS IN ITS MOST SIGNIFICANT NYBBLE AND A CODE FOR THE DAY-OF-WEEK IN ITS LEAST SIGNIFICANT NYBBLE. сUNDAY HAS CODE 1, мONDAY 2, ETC., сATURDAY 7, AND A CODE OF 0 MEANS "UNKNOWN". тHIS IS THE STANDARD FORMAT FOR ALL DATES USED IN аце. тHIS FORMAT IS ABSTRACTED AS "ыы:ыы:мм:дд:хх:мм:сс:тв". фOR DISK DEVICES THAT DON'T SUPPORT DATES, THIS FIELD WILL BE SET TO ALL ZEROES, WHICH CAN BE CONVENIENTLY INTERPRETED AS THE нулл DATE, NEGATIVE INFINITY, OR AS THE TIME THAT й.ц. WAS A SEVEN-YEAR-OLD BOY. дирент-тыпе: "ACEдIRENTтYPE" IS A THREE-CHARACTER (FOUR-BYTE) NULL-TERMINATED STRING. иT INDICATES WHAT TYPE THE FILE IS, IN LOWERCASE петсции. сTANDARD TYPES SUCH AS "сея" AND "прг" WILL BE RETURNED, AS WELL AND OTHER POSSIBILITIES FOR CUSTOM DEVICE DRIVERS. дирент-флагс: "ACEдIRENTфLAGS" IS A ONE-BYTE FIELD THAT IS INTERPRETED AS CONSISTING OF EIGHT INDEPENDENT ONE-BIT FIELDS. тHE ABSTRACT VIEW OF THE FIELDS IS "DRWX*-ET". "D" MEANS THAT THE ITEM IS A SUBDIRECTORY (OTHERWISE IT IS A REGULAR FILE), "R" MEANS THE ITEM IS READABLE, "W" MEANS THE ITEM IS WRITABLE, AND "X" MEANS THE ITEM IS EXECUTABLE. тHE "X" OPTION IS REALLY NOT SUPPORTED CURRENTLY. "*" MEANS THE ITEM IS IMPROPERLY CLOSED (A "SPLAT" FILE IN цOMMODORE-дос TERMINOLOGY). тHE "-" FIELD IS CURRENTLY UNDEFINED. "E" MEANS THAT THE VALUE GIVEN IN THE "ACEдIRENTбYTES" FIELD IS ACTUALLY EXACT, AND "T" MEANS THE FILE SHOULD BE INTERPRETED AS BEING A "TEXT" FILE (OTHERWISE, ITS TYPE IS EITHER BINARY OR UNKNOWN). тHE BIT FIELDS ARE ALL BOOLEANS; A VALUE OF "1" MEANS TRUE, "0", FALSE. тHE "D" BIT OCCUPIES THE 128-BIT POSITION, ETC. дирент-наме-лен: "ACEдIRENTнAMEлEN" IS A ONE-BYTE NUMBER. иT GIVES THE NUMBER OF CHARACTERS IN THE FILENAME. иT IS PRESENT FOR CONVENIENCE. дирент-наме: "ACEдIRENTнAME" IS A 16-CHARACTER (17-BYTE) NULL-TERMINATED CHARACTER STRING FIELD. иT GIVES THE NAME OF THE FILE OR DIRECTORY OR DISK. фILENAMES USED WITH аце ARE LIMITED TO 16 CHARACTERS. 2.3. сыстем цонстантс тHERE ARE SEVERAL SYMBOLIC CONSTANTS THAT ARE USED WITH THE аце SYSTEM INTERFACE: сымбол десцриптион ------------------- ------------------------- ACEаPPаDDRESS THE START ADDRESS OF APPLICATIONS ACEид1 THE ID CHARACTERS USED TO IDENTIFY аце APPLICATIONS ACEид2 ... ACEид3 ... ACEмEMнULL THE FAR MEMORY TYPE CODE USED TO INDICATE NULL PTRS ACEмEMреу FAR MEM TYPE CODE FOR рAM еXPANSION уNIT MEMORY ACEмEMиNTERNAL FAR MEM TYPE CODE FOR INTERNAL MEMORY ACEмEMрлреу FAR MEM TYPE CODE FOR реу MEMORY ACCESSED THRU рамлINK ACEмEMрл FAR MEM TYPE CODE FOR DIRECT-ACCESS рамлINK MEMORY ACEеRRсTOPPED ERROR CODE FOR SYSCALL ABORTED BY стоп KEY ACEеRRтOOмANYфILES ERR: TOO MANY FILES ALREADY OPENED TO OPEN ANOTHER ACEеRRфILEоPEN ERR: DON'T KNOW WHAT THIS MEANS ACEеRRфILEнOTоPEN ERR: THE GIVEN FILE DESCRIPTOR IS NOT ACTUALLY OPEN ACEеRRфILEнOTфOUND ERR: NAMED FILE TO OPEN FOR READING DOES NOT EXIST ACEеRRдEVICEнOTпRESENT ERR: THE SPECIFIED PHYSICAL DEVICE IS NOT ONLINE ACEеRRфILEнOTиNPUT ERR: FILE CANNOT BE OPENED FOR READING ACEеRRфILEнOTоUTPUT ERR: FILE CANNOT BE OPENED FOR WRITING ACEеRRмISSINGфILENAME ERR: PATHNAME COMPONENT IS THE NULL STRING ACEеRRиLLEGALдEVICE ERR: THE SPECIFIED DEVICE CANNOT DO WHAT YOU WANT ACEеRRвRITEпROTECT ERR: TRYING TO WRITE TO A DISK THAT IS WRITE-PROTECTED ACEеRRфILEеXISTS ERR: TRYING TO OPEN FOR WRITING FILE THAT EXISTS ACEеRRфILEтYPEмISMATCH ERR: YOU SPECIFIED THE FILE TYPE INCORRECTLY ACEеRRнOцHANNEL ERR: TOO MANY OPEN FILES ON DISK DRIVE TO OPEN ANOTHER ACEеRRиNSUFFICIENTмEMORY ERR: аце COULD NOT ALLOCATE THE MEMORY YOU REQUESTED ACEеRRоPENдIRECTORY ERR: YOU ARE TRYING TO OPEN A DIR AS IF IT WERE A FILE ACEеRRдISKоNLYоPERATION ERR: TRYING TO PERFORM DISK-ONLY OP ON CHAR DEVICE ACEеRRнULLпOINTER ERR: TRYING TO DEREFERENCE A NULL FAR POINTER ACEеRRиNVALIDфREEпARMS ERR: BAD CALL TO "PAGEFREE": MISALIGNED/WRONG SIZE ACEеRRфREEнOTоWNED ERR: TRYING TO FREE FAR MEMORY YOU DON'T OWN STDIN FILE DESCRIPTOR RESERVED FOR STDIN INPUT STREAM STDOUT FILE DESCRIPTOR RESERVED FOR STDOUT OUTPUT STREAM STDERR FILE DESCRIPTOR RESERVED FOR STDERR OUTPUT STREAM "ACEаPPаDDRESS", AS DISCUSSED BEFORE, IS THE ADDRESS THAT APPLICATION PROGRAMS ARE LOADED INTO MEMORY AT. тHEY MUST, OF COURSE, BE COMPILED TO EXECUTE STARTING AT THIS ADDRESS. тHE "ACEмEM" GROUP OF CONSTANTS ARE FOR USE WITH THE "PAGEALLOC" SYSTEM CALL, EXCEPT FOR "ACEмEMнULL", WHICH MAY BE USED BY APPLICATION PROGRAMS FOR INDICATING NULL FAR POINTERS. тHE "PAGEALLOC" CALL ALLOWS YOU TO SPECIFY WHAT TYPES OF MEMORY YOU ARE WILLING TO ACCEPT. тHIS IS IMPORTANT BECAUSE THE DIFFERENCE TYPES OF MEMORY HAVE DIFFERENT PERFORMANCE CHARACTERISTICS. аце WILL TRY TO GIVE YOU THE FASTEST MEMORY THAT IS AVAILABLE. рAM еXPANSION уNIT MEMORY HAS STARTUP AND BYTE-TRANSFER TIMES OF ABOUT 60 US (MICROSECONDS) AND 1 US, RESPECTIVELY. тHIS IS THE FASTEST TYPE OF FAR MEMORY. иNTERNAL MEMORY HAS A STARTUP TIME OF 24 US AND A BYTE-TRANSFER TIME OF BETWEEN 7 AND 14 US (DEPENDING ON WHETHER ACCESSING рам0 OR рам1+). реу MEMORY ACCESSED THROUGH A рамлINK HAS A TERRIBLE STARTUP TIME OF 1000 US AND A BYTE-TRANSFER TIME OF 2 US. дIRECT-ACCESS рамлINK MEMORY HAS A STARTUP TIME OF 1000 US AND A BYTE-TRANSFER TIME OF 16 US. аLL THESE TIMES ARE FOR THE ц128 IN 2 мхZ MODE. тHE "ACEеRR" GROUP GIVES THE ERROR CODES RETURNED BY SYSTEM CALLS. тHE ERROR CODES ARE RETURNED IN THE "ERRNO" VARIABLE. нOT ALL POSSIBLE ERROR CODES FROM цOMMODORE DISK DRIVES ARE COVERED, BUT THE IMPORTANT ONES ARE. фINALLY, THE "STD" FILES GROUP GIVE THE SYMBOLIC FILE DESCRIPTOR IDENTIFIERS OF THE DEFAULT INPUT, OUTPUT, AND ERROR OUTPUT FILE STREAMS. 2.4. сыстем цаллс аLL SYSTEM CALLS ARE CALLED BY SETTING UP ARGUMENTS IN SPECIFIED PROCESSOR REGISTERS AND MEMORY LOCATIONS, EXECUTING A йср TO THE SYSTEM CALL ADDRESS, AND PULLING THE RETURN VALUES OUT OF PROCESSOR REGISTERS AND MEMORY LOCATIONS. 2.1. филе цаллс наме : OPEN пурпосе: OPEN A FILE аргс : (ZP) = PATHNAME .а = FILE MODE ("R", "W", OR "A") ретурнс: .а = FILE DESCRIPTOR NUMBER .цс = ERROR OCCURRED FLAG алтерс : .ь, .ы, ERRNO оPENS A FILE. тHE NAME OF THE FILE IS GIVEN BY A POINTER TO A NULL-TERMINATED STRING, AND MAY CONTAIN DEVICE NAMES AND PATHNAMES AS SPECIFIED IN THE аце USER DOCUMENTATION. тHE FILE MODE IS A петсции CHARACTER. "R" MEANS TO OPEN THE FILE FOR READING, "W" MEANS TO OPEN THE FILE FOR WRITING, AND "A" MEANS TO OPEN THE FILE FOR APPENDING (WRITING, STARTING AT THE END OF THE FILE). аN ERROR WILL BE RETURNED IF YOU ATTEMPT TO OPEN FOR READING OR APPENDING A FILE THAT DOES NOT EXIST, OR IF YOU ATTEMPT TO OPEN FOR WRITING A FILE THAT DOES ALREADY EXIST. иF YOU WISH TO OVERWRITE AN EXISTING FILE, YOU WILL HAVE TO CALL "REMOVE" TO DELETE THE OLD VERSION BEFORE OPENING THE NEW VERSION FOR WRITING. тHE FUNCTION RETURNS A FILE DESCRIPTOR NUMBER, WHICH IS A SMALL UNSIGNED INTEGER THAT IS USED WITH OTHER FILE CALLS TO SPECIFY THE FILE THAT HAS BEEN OPENED. фILE DESCRIPTORS NUMBERED 0, 1, AND 2 ARE USED FOR STDIN, STDOUT, AND STDERR, RESPECTIVELY. тHE FILE DESCRIPTOR RETURNED WILL BE THE MINIMUM NUMBER THAT IS NOT CURRENTLY IN USE. тHESE NUMBERS ARE SYSTEM-WIDE (RATHER THAN LOCAL TO A PROCESS AS IN уNIX), AND THIS HAS SOME IMPLICATIONS FOR и/о REDIRECTION (SEE THE "FDSWAP" CALL BELOW). рESTRICTIONS: ONLY SO MANY кERNAL FILES ALLOWED TO BE OPEN ON A DISK DEVICE, AND THERE IS A SYSTEM MAXIMUM OF OPEN FILES. ыOU WILL GET A "TOO MANY FILES" ERROR IF YOU EVER EXCEED THIS LIMIT. аLSO, BECAUSE OF THE NATURE OF цOMMODORE-дос, THERE MAY BE EVEN TIGHTER RESTRICTIONS ON THE NUMBER OF FILES THAT CAN BE SIMULTANEOUSLY OPEN ON A SINGLE DISK DEVICE, RESULTING IN A "NO CHANNEL" ERROR. нOTE THAT THIS CALL CHECKS THE STATUS CHANNEL OF цOMMODORE DISK DRIVES ON EACH OPEN, SO YOU DON'T HAVE TO (AND SHOULD NOT ANYWAY). иF THE CURRENT PROGRAM EXITS EITHER BY CALLING "EXIT" OR SIMPLY BY DOING THE LAST ртс, ALL FILES THAT WERE OPENED BY THE PROGRAM AND ARE STILL OPEN WILL BE AUTOMATICALLY CLOSED BY THE SYSTEM BEFORE RETURNING TO THE PARENT PROGRAM. наме : CLOSE пурпосе: CLOSE AN OPEN FILE аргс : .а = фILE DESCRIPTOR NUMBER ретурнс: .цс = ERROR OCCURRED FLAG алтерс : .а, .ь, .ы, ERRNO цLOSES AN OPEN FILE. нOT MUCH TO SAY ABOUT THIS ONE. наме : READ пурпосе: READ DATA FROM AN OPEN FILE аргс : .ь = фILE DESCRIPTOR NUMBER (ZP) = POINTER TO BUFFER TO STORE DATA INTO .аы = MAXIMUM NUMBER OF BYTES TO READ ретурнс: (ZW) = .аы=NUMBER OF BYTES ACTUALLY READ IN .цс = ERROR OCCURRED FLAG .зс = еоф REACHED FLAG алтерс : .ь, ERRNO рEADS DATA FROM THE CURRENT POSITION OF AN OPEN FILE. уP TO THE SPECIFIED MAXIMUM NUMBER OF BYTES WILL BE READ. ыOU SHOULD NOT GIVE A MAXIMUM OF ZERO BYTES, OR YOU MAY MISINTERPRET AN еоф (END OF FILE). тHE BUFFER MUST BE AT LEAST THE SIZE OF THE MAXIMUM NUMBER OF BYTES TO READ. тHE DATA ARE NOT INTERPRETED IN ANY WAY, SO IT IS THE PROGRAMMER'S RESPONSIBILITY TO SEARCH FOR CARRIAGE RETURN CHARACTERS TO LOCATE LINES OF INPUT, IF HE SO DESIRES. хOWEVER, FOR THE CONSOLE THE INPUT IS NATURALLY DIVIDED UP INTO LINES, SO EACH CALL WILL RETURN AN ENTIRE LINE OF BYTES IF THE BUFFER IS LARGE ENOUGH. тHERE ARE NO GUARANTEES ABOUT THE NUMBER OF BYTES THAT WILL BE RETURNED, EXCEPT THAT IT WILL BE BETWEEN 1 AND THE BUFFER SIZE. сO, IF YOU WISH TO READ A CERTAIN NUMBER OF BYTES, YOU MAY HAVE TO MAKE MULTIPLE READ CALLS. тHE CALL RETURNS THE NUMBER OF BYTES READ IN BOTH THE .аы REGISTER PAIR AND IN (ZW), FOR ADDED CONVENIENCE. [нOTE: IN аце рELEASE #9, THE NUMBER OF BYTES READ ARE RETURNED ONLY IN THE .аы REGISTERS, NOT IN (ZW).] а RETURN OF ZERO BYTES READ MEANS THAT THE END OF THE FILE HAS BEEN REACHED. аN ATTEMPT TO READ BEYOND THE END OF FILE WILL SIMPLY GIVE ANOTHER еоф RETURN. еND OF FILE IS ALSO RETURNED IN THE .з FLAG OF THE PROCESSOR. наме : WRITE пурпосе: WRITE DATA TO AN OPEN FILE аргс : .ь = FILE DESCRIPTOR NUMBER (ZP) = POINTER TO DATA TO BE WRITTEN .аы = LENGTH OF DATA TO BE WRITTEN IN BYTES ретурнс: .цс = ERROR OCCURRED алтерс : .а, .ь, .ы, ERRNO вRITES DATA AT THE CURRENT POSITION OF AN OPEN FILE. [нOTE: аце рELEASE #9 ALSO ALTERS LOCATIONS (ZW) WHEN WRITING TO THE CONSOLE. тHIS PROBLEM WILL BE CORRECTED.] наме : FASTOPEN пурпосе: OPEN A FILE FOR FAST READING аргс : (ZP) = нAME .а = FILE MODE (MUST BE "R") ретурнс: .а = FILE DESCRIPTOR NUMBER .цс = ERROR OCCURRED FLAG алтерс : .ь, .ы, ERRNO тHIS PERFORMS THE SAME FUNCTION AS THE REGULAR "OPEN" CALL, EXCEPT THIS STYLE OF FILE ACCESSING WILL ALLOW FILES TO BE READ MUCH FASTER THAN THE OTHER. оN DEVICES THAT ARE SO EQUIPPED, THE "FASTLOAD" BURST COMMAND IS USED (SIMILAR SHORTCUTS MAY BE POSSIBLE WITH OTHER DEVICES TOO). тHE DRAWBACK OF THIS INCREASED SPEED IS THAT NO OTHER DEVICE и/о CAN TAKE PLACE WHILE A FILE IS OPENED FOR "FAST" ACCESS, NOT EVEN TO OTHER DEVICES, EXCEPT FOR OUTPUT TO THE CONSOLE. оTHER FILES CAN BE OPEN, JUST NOT ACCESSED. ыOU ALSO CANNOT OPEN MORE THAN ONE "FAST" FILE AT A TIME. иNTERRUPTS WILL BE DISABLED WHILE A FILE IS OPEN FOR FAST ACCESSING, SO THE USER CANNOT RE-ENABLE THEM, FOR TECHNICAL REASONS. тHE ARGUMENTS TO THIS CALL ARE EXACTLY THE SAME AS THE REGULAR "OPEN" TO MAKE IT EASY TO SWITCH FROM USING ONE TO THE OTHER. [нOTE: THESE "FAST" CALLS DO NOT EXIST IN рELEASE #9]. наме : FASTCLOSE пурпосе: CLOSE THE FILE THAT WAS OPENED FOR FAST READING аргс : .а = фILE DESCRIPTOR NUMBER ретурнс: .цс = ERROR OCCURRED FLAG алтерс : .а, .ь, .ы, ERRNO цLOSES THE FILE THAT WAS OPENED FOR FAST READING. наме : FASTREAD пурпосе: READ DATA FROM THE FILE OPENED FOR FAST READING аргс : .ь = фILE DESCRIPTOR NUMBER (ZP) = POINTER TO BUFFER TO STORE DATA INTO .аы = MAXIMUM NUMBER OF BYTES TO READ ретурнс: (ZW) = .аы=NUMBER OF BYTES ACTUALLY READ IN .цс = ERROR OCCURRED FLAG .зс = еоф REACHED FLAG алтерс : .ь, ERRNO рEAD DATA FROM THE (ONE) FILE THAT IS CURRENTLY OPENED FOR "FAST" READING. тHE ARGUMENTS AND SEMANTICS ARE EQUIVALENT TO THE REGULAR "READ" CALL. наме : BLOAD пурпосе: BINARY LOAD аргс : (ZP) = PATHNAME .аы = ADDRESS TO LOAD FILE (ZW) = HIGHEST ADDRESS THAT FILE MAY OCCUPY, PLUS ONE ретурнс: .аы = END ADDRESS OF LOAD, PLUS ONE .цс = ERROR OCCURRED FLAG алтерс : .ь, ERRNO бINARY-LOAD A FILE DIRECTLY INTO MEMORY. иF THE FILE WILL NOT FIT INTO THE SPECIFIED SPACE, AN ERROR WILL BE RETURNED AND THE LOAD TRUNCATED IF THE DEVICE SUPPORTS TRUNCATION; OTHERWISE, IMPORTANT DATA MAY BE OVERWRITTEN. наме : REMOVE пурпосе: DELETE A FILE аргс : (ZP) = PATHNAME ретурнс: .цс = ERROR OCCURRED FLAG алтерс : .а, .ь, .ы, ERRNO дELETE THE NAMED FILE. наме : RENAME пурпосе: RENAME A FILE OR DIRECTORY аргс : (ZP) = OLD FILENAME (ZW) = NEW FILENAME ретурнс: .цс = ERROR OCCURRED FLAG алтерс : .а, .ь, .ы, ERRNO рENAMES A FILE OR DIRECTORY. иF A FILE WITH THE NEW NAME ALREADY EXISTS, THEN THE OPERATION WILL BE ABORTED AND A "FILE EXISTS" ERROR WILL BE RETURNED. оN MOST DEVICES, THE FILE TO BE RENAMED MUST BE IN THE CURRENT DIRECTORY AND THE NEW NAME MAY NOT INCLUDE ANY PATH, JUST A FILENAME. наме : DEVINFO пурпосе: GIVE INFORMATION ABOUT DEVICE аргс : .ь = FILE DESCRIPTOR NUMBER ретурнс: .а = DEVICE TYPE CODE .ь = NUMBER OF COLUMNS ON DEVICE .ы = NUMBER OF ROWS PER "PAGE" OF DEVICE .цс = ERROR OCCURRED FLAG алтерс : ERRNO тHIS CALL RETURNS INFORMATION ABOUT THE DEVICE OF AN OPEN FILE. тHERE ARE FOUR POSSIBLE VALUES FOR THE DEVICE TYPE CODE: 0==CONSOLE, 1==CHARACTER-ORIENTED DEVICE, AND 2==DISK DEVICE. тHE NUMBER OF ROWS AND COLUMNS PER "PAGE" OF THE DEVICE ARE ALSO RETURNED. фOR THE CONSOLE, THIS WILL BE THE CURRENT WINDOW SIZE. фOR A CHARACTER-ORIENTED DEVICE, IT WILL BE THE NATURAL SIZE (TYPICALLY 80 COLUMNS BY 66 ROWS), AND FOR A DISK, IT WILL BE 40 COLUMNS IN 64 MODE OR 80 COLUMNS IN 128 MODE, BOTH BY 66 ROWS. наме : FDSWAP пурпосе: SWAP TWO FILE DESCRIPTOR NUMBERS аргс : .ь = FIRST FILE DESCRIPTOR NUMBER .ы = SECOND FILE DESCRIPTOR NUMBER ретурнс: .цс = ERROR OCCURRED FLAG алтерс : .а, .ь, .ы, ERRNO тHIS CALL SWAPS MEANINGS OF TWO FILE DESCRIPTOR NUMBERS. тHE FILE DESCRIPTORS MAY BE EITHER IN USE OR NOT USE WHEN THE CALL IS MADE. тHIS CALL IS INTENDED TO BE USED TO REDIRECT THE STDIN, STDOUT, AND STDERR FILE STREAMS. тO DO THIS, SIMPLY OPEN THE NEW FILE INTENDED TO BE, FOR EXAMPLE, STDOUT, AND SWAP THE FILE DESCRIPTOR NUMBER RETURNED FROM THE OPEN WITH FILE DESCRIPTOR NUMBER 1 (STDOUT). пOOF. тHEN CALL YOUR SUBROUTINE OR EXTERNAL PROGRAM, AND ON RETURN, SWAP THE TWO FILE DESCRIPTORS BACK, AND CLOSE THE REDIRECTION FILE. 2.2. дирецторы цаллс наме : DIROPEN пурпосе: OPEN A DIRECTORY FOR SCANNING ITS DIRECTORY ENTRIES аргс : (ZP) = DIRECTORY PATHNAME ретурнс: .а = FILE DESCRIPTOR NUMBER .цс = ERROR OCCURRED FLAG алтерс : .ь, .ы, ERRNO тHIS CALL OPENS A DIRECTORY FOR READING ITS ENTRIES. иT RETURNS A "FILE" DESCRIPTOR NUMBER TO YOU TO USE FOR READING SUCCESSIVE DIRECTORY ENTIRES WITH THE "DIRREAD" CALL. тHE PATHNAME THAT YOU GIVE TO THIS CALL MUST BE A PROPER DIRECTORY NAME LIKE "A:" OR "C:2//C64/GAMES/:", ENDING WITH A COLON CHARACTER. ыOU CAN HAVE DIRECTORIES FROM MULTIPLE DEVICES OPEN FOR READING AT ONE TIME, BUT YOU CANNOT HAVE THE DIRECTORY OF ONE DEVICE OPEN MULTIPLE TIMES. аLSO NOTE THAT YOU CANNOT PASS WILDCARDS TO THIS CALL; YOU WILL RECEIVE THE ENTIRE DIRECTORY LISTING. наме : DIRCLOSE пурпосе: CLOSE A DIRECTORY OPENED FOR SCANNING аргс : .а = FILE DESCRIPTOR NUMBER ретурнс: .цс = ERROR OCCURRED FLAG алтерс : .а, .ь, .ы, ERRNO цLOSES A DIRECTORY THAT IS OPEN FOR READING. ыOU CAN MAKE THIS CALL AT ANY POINT WHILE SCANNING A DIRECTORY; YOU DO NOT HAVE TO FINISH SCANNING AN ENTIRE DIRECTORY FIRST. наме : DIRREAD пурпосе: READ THE NEXT DIRECTORY ENTRY FROM AN OPEN DIRECTORY аргс : .ь = FILE DESCRIPTOR NUMBER ретурнс: .з = END OF DIRECTORY FLAG .цс = ERROR OCCURRED FLAG ACEдIRENTбUFFER = NEW DIRECTORY ENTRY DATA алтерс : .а, .ь, .ы, ERRNO рEADS THE NEXT DIRECTORY ENTRY FROM THE SPECIFIED OPEN DIRECTORY INTO THE SYSTEM INTERFACE GLOBAL VARIABLE "ACEдIRENTбUFFER" DESCRIBED EARLIER. аFTER OPENING A DIRECTORY FOR READING, THE FIRST TIME YOU CALL THIS ROUTINE, YOU WILL RECEIVE THE NAME OF THE DISK (OR DIRECTORY). тHE "ACEдIRENTнAMEлEN" AND "ACEдIRENTнAME" FIELDS ARE THE ONLY ONES THAT