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IBM BASIC Directory
Can you tell me how to read and display the disk directory on an IBM PC from within a BASIC program?

 There are two simple ways to approach this. The first is simply to print the directory to the screen at the appropriate time in your BASIC program. A second method would be to read the directory into a string array for use by your program at some later point. Here's a short routine that employs the first method:

EG 100 REM FSPEC$="A:*.*":GOTO 1
       40
MD 110 PRINT:PRINT"Select drive:
        (";:COLOR 16,15:PRINT"A
       B";:COLOR 7,0:PRINT CHR$(
       29)CHR$(29)"/"CHR$(28)")"
HB 120 DRIVE$=INKEY$+":":A=ASC(D
       RIVE$):IF (A OR 32)<97 OR
       (A OR 32)>98 THEN 120
IF 130 DRIVE$=CHRS(A AND 223)+":
       ":FSPEC$=DRIVE$+"*.*"
GG 140 ON ERROR GOTO 150:FILES F
       SPEC$:ON ERROR GOTO 0:END
JL 150 BEEP:COLOR 31:CLS:PRINT "
       Cannot read directory":CO
       LOR 7:ON ERROR GOTO 0:END

    This routine will ask you from which drive (A: or B:) you want to read the directory. If you have a single-drive system (drive A: only), remove the REM from line 100. Here's another routine that uses the second method:

KJ 1000 REM FSPEC$="A:*.*":GOTO
        1040
LH 1010 PRINT:PRINT"Select drive
        : (";:COLOR 16,15:PRINT"
        A B";:COLOR 7,0:PRINT CH
        R$(29)CHR$(29)"/"CHR$(28
        )")"
HC 1020 DRIVE$=INKEY$+":":A=ASC(
        DRIVE$):IF (A OR 32)<97
        OR (A OR 32)>98 THEN 102
        0
ME 1030 DRIVE$=CHR$(A AND 223)+"
        :":FSPEC$-DRIVE$+"*.*"
LN 1040 DEF SEG=0:WIDTH 80
IF 1050 HEAD=1050:TAIL=1052:BUFF
        ER=1054
OJ 1060 CLS:COLOR 23,0,0:PRINT"R
        eadinq disk directory"
OE 1070 COLOR 0:ON ERROR GOTO 10
        90
EJ 1080 FILES FSPEC$:ON ERROR GO
        TO 0:GOTO 1100
IL 1090 BEEP:COLOR 31:CLS:PRINT
        "Cannot read directory":
        COLOR 7:ON ERROR GOTO 0:
        END
HF 1100 DIM TT$(24):LOCATE 3,1:C
        OLOR 7:ROWS=0
CD 1110 POKE HEAD,30:POKE TAIL,3
        4:POKE BUFFER,0:POKE BUF
        FER+1,79:POKE BUFFER+2,1
        3:POKE BUFFER+3,28:'Put
        code for End, Enter into
         keyboard
DE 1120 LINE INPUT TT$(ROWS):IF
        TT$(ROWS)<>"" THEN ROWS
        ROWS+1:GOTO 1110
DN 1130 IF NOT DIMMED THEN DIM F
        $(ROWS*4-1):DIMMED-1
JP 1140 ROWS=ROWS-1:FOR I=0 TO R
        OWS:FOR J=0 TO 3
KE 1150 T$=MID$(TT$(I),J*18+1,12
        )
KD 1160 IF T$<>"" THEN F$(ENTRIE
        S)=T$:ENTRIES=ENTRIES+1
KA 1170 NEXT J:NEXT I:ERASE TT$:
        ENTRIES=ENTRIES-1:DEF SE
        G:RETURN


    This routine reads the filenames from the disk directory into an array named F$. One advantage of this method is that you need to look only once at the directory. Once the directory information is stored in a string, you can extract the filenames whenever it's convenient and print them in any format you like. With a little more programming, you could cursor through the directory to access a particular file, sort the directory entries alphabetically, catalog all your disks, or whatever. Again, remove the REM from line 1000 if you have a single-drive system.