Commodore 1581 - Demonstration of Sequential Files (BASIC 7.0)

DEMONSTRATION OF SEQUENTIAL FILES
(BASIC 7.0)
Use the following program for your first experiments with sequen
tial files. Comments have been added to help you better understand it.
150CR$ = CHR$(13)
170 PRINT CHR$(147):REM CLEAR
SCREEN
190 PRINT "** WRITE A FILE **"
210 PRINT
220 DOPEN #2,"@SEQ FILE",W
230 GOSUB 500
240 PRINT'ENTER A WORD,
THEN A NUMBER"
250 PRINT'OR 'END,0' TO STOP"
260 PRINT
270 INPUT A$,B
280 PRINT#2A$;CR$;B
290 GOSUB 500
300 IF A$O"END" THEN 270
310 PRINT
320 DCLOSE #2
340 PRINT "** READ SAME FILE
BACK **"
360 PRINT
370 DOPEN #2,"SEQ FILE"
380 GOSUB 500
390 INPUT#2A$3
400RS = ST
410 GOSUB 500
420 PRINT A$,B
430 IF RS = 0 THEN 390
440 IF RSO64 THEN
PRINT"STATUS = ";RS
450 DCLOSE #2
460 END
480 REM ** ERROR CHECK S/R **
500 IF DS>0 THEN PRINT DS$:STOP
510 RETURN
Make a carriage return variable
Open demo file with replace
Check for disk errors
Accept a string & number
from keyboard
Write them to the disk file
Until finished
Tidy up
Reopen same file for reading
Read next string & number
from file
Remember file status
Display file contents
until done,
unless there's an error
Then quit
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