10	 ! DATECOR.BAS
	 ! TO CORRECT ".LOG" FILES WITH 79 INSTEAD OF 80 DATES
	 ! FROM DAMAGE CAUSED BY INCORRECT SYSTEM
	 ! TIME SETTING OR OTHER ERRORS
12 DIM A$[56],N$[20]V,B$[56],C$[12]
210 INPUT "USER ";N$
220 OPEN #3,N$+".LOG/MO/RN/SH/LN:56"
230 N=NRC(3)
240 PRINT "TOTAL RECORDS =";N
245 DF=0
250 FOR I=1 TO N
295 INPUT LINE #3@I,A$
297 IF DF=1 GOTO 350		: ! IF 1980 SEEN, CHECK FOR 1979
300 IF SBS$(A$,7,2)="80" THEN DF=1	: ! CHECK FOR FIRST 1980 DATE
305 IF SBS$(A$,26,2)="80" THEN DF=1
310 IF DF<>1 GOTO 450		: ! DATE IS OK
350 IF SBS$(A$,7,2)="79" GOTO 400
360 IF SBS$(A$,26,2)="79" GOTO 400
370 GOTO 450			: ! RECORD IS OK
400 ! CALC CORRECT DATES
401			 ! 12/XX/79 LOGIN AND 01/XX/80 LOGOUT IS OK
402 IF SBS$(A$,7,2)="79" AND SBS$(A$,26,2)="80" AND SBS$(A$,1,2)="12" GOTO 450
405 DA=DCEN(SBS$(A$,20,6)+"80")-DCEN(SBS$(A$,1,6)+"80")
407 HR=VAL(SBS$(A$,29,2))-VAL(SBS$(A$,10,2))
409 MI=VAL(SBS$(A$,32,2))-VAL(SBS$(A$,13,2))
411 SE=VAL(SBS$(A$,35,2))-VAL(SBS$(A$,16,2))
413 IF SE<0 THEN SE=SE+60 : MI=MI-1
415 IF MI<0 THEN MI=MI+60 : HR=HR-1
417 IF HR<0 THEN HR=HR+24 : DA=DA-1
418 IF DA<0 THEN DA=DA+31
420 C$=FRMT$(DA,3)+":"+FRMT$(HR,2)+":"+FRMT$(MI,2)+":"+FRMT$(SE,2)
425 FOR J=1 TO 3
430 IF SBS$(C$,J*3+2,1)=" " THEN C$=SEG$(C$,1,J*3+1)+"0"+SEG$(C$,J*3+3,12)
435 NEXT J
440 B$=SEG$(A$,1,6)+"80"+SEG$(A$,9,25)+"80"+SEG$(A$,28,38)+C$+SEG$(A$,51,56)
442 PRINT #3@I,B$			: ! PRINT CORRECTED RECORD
443 PRINT 
444 PRINT "CORRECTED  ";A$
446 PRINT "TO READ    ";B$
450 NEXT I
500 CLOSE 3 : EXIT