EXAMPLES OF OPENING SEQUENTIAL FILES:
To create a sequential
file
of
phone numbers, you could use:
BASIC 7.0: DOPEN#2,
"PHONES"
,D0,U8,W
BASIC 2.0: OPEN 2,8,2, "0:PHONES,SEQUENTIAL,WRITE"
or
OPEN 2,8,2, "0:PHONES,S,W"
On the chance you've already got a
"PHONES"
file
on our diskette, you can avoid a
"FILE
EXISTS" error message by doing
an
@OPEN
BASIC 7.0: DOPEN#2,
"@PHONES",
D0,U8,W
BASIC 2.0: OPEN 2,8,2, "@0:PHONES,S,W"
This erases all your old phone numbers, so make sure that any information that may be
deleted is
of
no importance. After writing our phone file, remove the diskette and turn off
the system. To recall the data in the file, reopen it with something like:
BASIC 7 .0: DOPEN#8,
"PHONES"
,D0,U8
BASIC 2.0: OPEN 8,8,8, "0:PHONES,S,R"
It doesn't matter whether the
file
and channel numbers match the ones
we
used before, but
the file name does have to match. It's possible to use an abbreviation form
of
the
file
name,
if
there are no other files that would have the same abbreviation:
BASIC 7.0: DOPEN#1O,
"PH*"
,D0,U8
BASIC 2.0: OPEN 10,8,6, "0:PH*
,S,R"
If
you have too many phone numbers, they might not
fit
in one
file.
In
that case, use
several similar
file
names and let a program choose the correct file.
BASIC 7.0:
100 INPUT "WHICH PHONE FILE (1-3)";PH
110 IF
PH<>1
AND
PH<>2
AND
PH<>3
THEN
100
120 DOPEN#4,
"PHONE"
+ STR$(PH),D0,U8
BASIC 2.0:
100 INPUT "WHICH PHONE FILE (1-3)";PH
110 IF
PH<>1
AND
PH<>2
AND
PH<>3
THEN 100
120 OPEN 4,8,2,
"PHONE"
+ STR$(PH)
+"
,S,R"
You can omit the drive number on an OPEN command
to
read a file. Doing so allows
those with dual drives to search both diskettes for the
file.
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