section multi ut.con equ $C6 open a console cn.itod equ $F2 convert integer to decimal string sb.start equ $154 vectored entrypoint to start up an interpreter mt.inf equ 0 get system information mt.frjob equ 5 force remove a job io.open equ 1 open trap #2 code io.share equ 1 shared input sv_progd equ $ac PROG_USE default prefix file equ '>' delimiter at end of command file name rom equ '!' marker at end of string for forcing original ROM names tables equ $18 we'll have our tables at this offset area equ $D00 we can go with just 384, but this is more sensible! * With a bit of luck: * Use QX or EX to pass channels and/or command string. * If the last character of the command string is the "rom" marker, it is * removed from the string and the interpretter will start up with only the * original ROM names, instead of inherited names. * The remaining command string is then scanned for the "file" marker, and if * it's got it, the first part is opened as an input command channel, and the * rest is shuffled down. * The command string, what's left of it, becomes CMD$ in the interpreted basic. * Channels passed: * None: If no file marker in the comman string, a standard set of * windows is opened for #0, #1 and #2. * One: Slotted in as both #0 and #1 * Two: Become #0 and #1 * More: First two become #0 and #1, #2 is missed out, and the rest go * in as channels #3 onward. * E.g. A filter to change replace strings in a file: * AUTO * i%='/'INSTR cmd$:a$='':IF i%:a$=cmd$(i%+1TO):cmd$=cmd$(TO i%-1) * l%=LEN(cmd$) * REP lp1 * IF EOF(#0):EXIT lp1 * INPUT#3;i$:IF l% * REP lp2:i%=cmd$INSTR i$:IF i%: ... * ... PRINT i$(TO i%-1);a$;:i$=i$(i%+l%TO):ELSE EXIT lp2 * ENDIF:PRINT i$:ENDREP lp1 * With the above as "subs" and this program as "multi", both in the program * default directory, use: * EX multi,infile,outfile;'subs>fred/jim' * Then all occurrances of "fred" in the source file "infile" will be replaced, * creating the new file in "outfile", where these files are in the default data * directory. * A further tweak is permitted: we may even tell the new interpreter to use a * specified set of m/c names by giving it a positive value in register a1. * This option is just a bit wierd and we don't support it at the moment. * We have to be able to find the tables in an interpretted job, other than job * zero, so we've invented a system: * word two MUST have the offset of the tables in it. * Note: MultiBasics cannot be re-activated, the vector entry sorts this out. * If no channels or command string at all are passed in, we do a default case * which is marginally more friendly than always getting the default windows. * We construct a single window in one of several screen positions dependant on * the job number. This is made to become both channels #0 and #1. * The windows are small, but just about give you enough to work with. * They are such that they do not overlap one another, and they all fit inside * the TV default channel #1/#2 area; convenient for an unexpanded m/c. * We let them have an extra pixel row and column versus the exact character * grid, as this means normal characters do not ever touch the borders. * With the above constraints, 2*N windows are what we go for; two across, and N * down the screen. N equ 3 windows down the screen (1..15 will work) * The way thing go, changing N to 1, 2, 3, 4, 6, 8 and 15 windows will give 19, * 9, 6, 4, 3, 2 and one lines for each window respectively. * Notes on "hotkey"'ing programs.... * When a program is hotkey'ed, what happens is that the program code is stored * in a RESPR or common heap area, then when it is required to execute, an * appropriate area is acquired in the transient area, a long jump to the start * of the program code is stored taking 6 bytes. This is followed by the job * name, prefixed by its length, and possible a padding byte to get on an even * boundary. The remaining transient area is a data area as demanded by the job. * This code is then initiated in a standard fashion, so that A6 will be a * pointer to long jump and A4/A5 are the offsets to the bottom/top of the data * area. The program counter STARTS at A6, but then immediately jumps off into * the code stored in the common heap or resident area. * This code here is very careful not to confuse the meaning of A6 and PC, * which will differ for shared code as above. * One warning... to avoid getting really terribly clever, and to make the * offset from job start to A6 into a neat $80, this code is rather locked into * not having too long a start job name. Don't use the very clever QPAC2 idea of * supplying a new job name, unless it's less than 12 chars long! * You can patch the inbuilt job name to anything between 0 and 4 characters. multi moveq #mt.inf,d0 get our job number trap #1 bra.s base go start setting up dc.w $4AFB,nmex-name name dc.b 'SB.' we append our job number to this nmex ds.b 0 ds.w 0 base move.l sv_progd(a0),a3 we may like to use the PROG_USE prefix moveq #0,d6 move.w d1,d6 we'll use this in case we default setup divu #2*N,d6 job MOD possible default windows swap d6 move.w #name-multi,a0 add.w -2(a6,a0.l),a0 move.w #tables-2,a1 we will overwrite our code move.w cn.itod,a2 move.w d1,0(a6,a1.l) * NB. This had better be >= multi+tables now! jsr (a2) extend job name with job number add.w d1,name-2-multi(a6) a little used fact: d1 returns char count! move.l a1,(a6) put table offset at start of job + 2 add.l a1,a6 push on past base of our transient area sub.l a1,a5 discount it from the data area tst.l (sp) have we been given anything at all? bne.s useit yes - they've got TK2 or somesuch * Zilch being passed in, so let's be nice, and give them some defaults moveq #32,d1 lsr.w #1,d6 bcc.s xset lsl.w #3,d1 32<<3=256 x position 32(even)/256(odd) xset H equ (200/N-3)/10*10+3 height of windows, including border G equ (202-H*N)/(N+1) gaps between windows mulu #H+G,d6 add.w #16+(200-H*N-G*(N-1))/2,d6 top window y position move.w d6,(sp) set y move.w d1,-(sp) set x move.l #222<<16!H,-(sp) set width and height move.l #$FF010207,-(sp) set border colour/width, paper and ink move.l sp,a1 move.w ut.con,a2 jsr (a2) bne.s err addq.l #8,sp move.l a0,(sp) move.w #1,-(sp) bra.s nochan useit move.l sp,a4 moveq #0,d4 move.w (a4)+,d4 pick up channel count lsl.l #2,d4 add.l d4,a4 move on past them move.l a4,a2 remember start of command string move.w (a4)+,d4 get command string length cmp.b #rom,-1(a4,d4.w) are we being asked not to do ROM names? seq d5 ext.w d5 add.w d5,d4 no - set a zero move.w d4,(a2) yes - lose the byte and leave a minus one sclp subq.w #1,d4 bcs.s nochan didn't find our file marker cmp.b #file,(a4)+ is this our file marker? bne.s sclp no - keep looking * file marker found, d4 has remaining string length sub.w d4,(a2) the filename length plus the file marker subq.w #1,(a2) so this is the filename length move.l a2,a0 set filename start bsr.s open try to open plain name beq.s gotit if ok, go use it move.l a6,a0 fill it in down where out tables will go moveq #127,d2 silly upper limit on file name move.w d2,(a0)+ first put in the limit value bsr.s concat start with the default prefix * upper limit on file name is really (*-base-2), but that's more than 127! move.l a2,a3 bsr.s concat then add the plain name move.l a6,a0 sub.w d2,(a0) this is now the concatenated name length bsr.s open try to open prefixed name bne.s err no good, so we'll have to die! gotit move.w d4,(a2)+ cut string length back to what's left shlp subq.b #1,d4 bcs.s basic move.b (a4)+,(a2)+ copy remaining command string down bra.s shlp nochan sub.l a0,a0 no command channel basic move.w d5,a1 set inherit(0) or ROM(-ve) names move.w sb.start,a2 get entry vector jmp $4000(a2) a0/a5-a7 are set, so run off to basic! open moveq #-1,d1 we'll own it moveq #io.open,d0 moveq #io.share,d3 trap #2 move.l d0,d3 was the file opened OK? rts concat move.w (a3)+,d0 get length sub.w d0,d2 bge.s ccent err moveq #-1,d1 ourself moveq #mt.frjob,d0 force remove job trap #1 pcopy move.b (a3)+,(a0)+ ccent dbra d0,pcopy rts data base+area-* end