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INPUT/OUTPUT FUNCTIONS
25.3 -- Device Independent I/O Functions
3
Binary rec ord rormat.
Th is format ap pI
i
es to
both
diskette
and
non-diskette
files;
however,
non-diskette
riles
can
only
be
accessed in the Tile format mode (F
=
0
Or
IOCDTT) using this format.
4
This
format
is
undefined and should not be
used.
5
ASCI I recoi'd rormat.
ih
i
s format app 1 ies
to
both'
diskette
and
non-diskette
files.
Non-diskette riles
of
this
format
can
be
accessed
in
either
the
file format or the
non-file format modes.
ASCII
record
files
can
be
space
compressed,
but only
if
theq
reside on
diskette.
6
ihis
format is undefined and
should
not
be
used.
7
ASClI-converted-binary
record
format.
This
format usually applies to non-disxette files.
This
format
is
intended
to
be
used
for
~riting
binar~
record files rrom the diskette
to a non-diskette device that can only accept
seven-bit data bytes.
Otherwise,
this rormat
is identical to FMT = 3.
NOT USED (Bits 0-7) -- Reserved area
The
least
significant byte
of
the
IOCFDF rield
is reserved
ror
ruture expansion.
This
b~te
must
be
zero
ror
all
riles.
25.3.
1.
17 IOCDEN -- Di rec tory entry numb er
Associated
with
each
di~ectory
entry is a number,
the
directory entry number, which is a runction
Or
the
physical
location
of
the
entry within the directory.
The directory
entry number is not found anywhere in the
directory,
rather
it
is
a
calculated quantity.
The two-byte IOCDEN field is
supplied
by
the
system
after
the
.
OPEN
function
(section
25.3.3)
has been called.
It only applies to diskette files.
The contents
o~
!OCDEN should never be changed
by
the
calling
program.
The
IOCDEN field has the following format:
J
Page
25-30
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