Radio Shack TRS-80 Owner's Manual page 156

S-80
MODEL
SSI
DISK
SYSTEM
2,
field the buffer,
so
you can
3.
place data into
the buffer with
lset and rset
statements.
When
basic encounters
the statement:
put
nmexp
,nmexp2
it
does the following:
•
Gets the information
needed
to
access
the disk hie
•
Checks
the
access
mode
for
this
buffer
(must be
r)
•
Acquires
more
disk space for the
file if
necessary
to
accommodate
the record
indicated
by
nmexp2
9 Copies the buffer contents into the specified record of
the
disk
file
•
Updates
the current
record
number
to
equal
nmexp2
+
The
"current
record"
is
the
record
whose number
is
one
higher than the
last
record accessed.
The
first
time
you
access a
file
via a
particular buffer, the
current
record
is
set
equal
to
1
If
the record
number you put
is
higher than
the end-of-file
record
number,
then
nmexp2 becomes
the
new
end-of-file record
number.
LSET
and
ESET
Place
Data
in
a
Random
Buffer
Field
var$
- SMpSmi
asm
m$~
bmoS
vgr$i$
s field
name.
sjwf contains
tha cats
to
m
pissed
In
IN
buffet fiskj
nnrndA ay
vas-S.
These
two
statements
let
you
place character-string data
into fields
previously
set
up by
a
field
statement.
For example, suppose
nm$
and ad$ have been
defined
as field
names
for a
random
file
buffer.
nm$
has
a length
of
18 characters,
and ad$ has a length of
25
characters.
Now
we
want
to
place
the
following information
into the
buffer
fields so
it
can
be
written to disk:
138