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- 1 'Use this BASIC program on the PC if you have the printable file
- 2 'MSKERMIT.BOO already on the PC to convert it to an executable
- 3 'file. This program takes about 30 minutes to run on a PC with
- 4 'floppy disks.
- 5 ' Bill Catchings, June 1984
- 6 ' Columbia University Center for Computing Activities
-
- 10 t$ = time$ ' Save the time.
- 20 defint a-z ' Integer to gain some speed.
- 30 n$ = chr$(0)
- 40 z = asc("0")
- 50 t = asc("~")-z
- 60 def fnuchr%(a$)=asc(a$)-z
- 70 open "MSKERMIT.BOO" for input as #1
-
- 100 input#1,f$ ' Is this the right file?
- 110 if len(f$) > 20 then goto 900
- 120 open f$ for output as #2
- 130 print "Outputting to "+f$
-
- 200 if eof(1) then goto 800 ' Exit nicely on end of file.
- 210 input#1,x$ ' Get a line.
- 220 y$ = "" ' Clear the output buffer.
- 230 goto 400
-
- 300 print#2,y$; ' Print output buffer to file.
- 310 goto 200 ' Get another line.
-
- 400 if len(x$) = 0 goto 300 ' Is the input buffer empty?
- 410 a = fnuchr%(x$)
- 420 if a = t then goto 700 ' Null repeat character?
- 430 q$=mid$(x$,2,3) ' Get the quadruplet to decode.
- 440 x$=mid$(x$,5)
- 450 b = fnuchr%(q$)
- 460 q$ = mid$(q$,2)
- 470 c = fnuchr%(q$)
- 480 q$ = mid$(q$,2)
- 490 d = fnuchr%(q$)
-
- 500 y$ = y$ + chr$(((a * 4) + (b \ 16)) and 255) ' Decode the quad.
- 510 y$ = y$ + chr$(((b * 16) + (c \ 4)) and 255)
- 520 y$ = y$ + chr$(((c * 64) + d) and 255)
- 530 goto 400 ' Get another quad.
-
- 700 x$ = mid$(x$,2) ' Expand the nulls.
- 710 r = fnuchr%(x$) ' Get the number of nulls.
- 715 print " Null: ",r
- 720 x$ = mid$(x$,2)
- 730 for i=1 to r ' Loop, adding nulls to string.
- 740 y$ = y$ + n$
- 750 next
- 760 print#2,y$; ' Output the nulls to the file.
- 770 y$ = "" ' Clear the output buffer.
- 780 goto 400
-
- 800 print "Processing complete, elapsed time: "+t$+" to "+time$
- 810 print "Output in "+f$
- 820 close #1,#2
- 830 goto 9999
-
- 900 print "?The version of the MSKERMIT.BOO file is incorrect"
- 910 goto 820
-
- 9999 end
-