Radio Shack TRS-80 Trsdos & Disk Basic Reference Manual page 150

DISK BASIC
Disk
Storage during Sequential Access
One
thing that
makes sequential access so simple
is
that
you
can
generally ignore the
details
of disk storage.
You
just write
your
data
and read
it
back.
Described
below
are a
few of the technical
details
and
hints
you
should keep
in
the
back
of
your mind. In
some
situations,
they
will
become
important.
1
PRINT*
statements don't
write data
directly to
the disk;
instead,
the data
is
placed in
the
256-byte output
buffer.
When
this
buffer
is
filled,
the contents are
automatically
written to
disk.
(Closing the
file
will also
write the buffer
to
disk.)
2.
If a
DISK
FULL
ERROR
occurs during execution of
a
PRINT*
statement,
you
should
realize
that the current
contents of the
output
buffer
have not been
written to the
file.
The
data
in
the disk
file is
intact,
but
it
doesn't contain the
last
few
values
you
PRINTed
to
it.
If
your
variables
still
contain the data,
you
can recover
it
directly.
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