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INPUT/OUTPUT FUNCTIONS
. 25.3 -- Device Independent I/O Functions
F
E
D
c
B
A
9
8
7
6
4
3
2
1
o
: W
f
DIS :
C
~
N:
FMT
<--------
Not Used
(=0) -------)
File format bits
Non-compressed space bit
Contiguous allocation bit
System file bit
Delete protection bit
Write protection bit
The functions of the
varlOUS
bits
Q,_
described below:
W (Bit F) -- Write protection bit
The
"w
n
bi't only applies
to
diskette files.
If
this bit is set to onel
the rile can only be accessed
with input requests.
Any IIO
functions that
attempt
to
write
to a rile with the
"W"
bit set will return
an error.
In addition,
the file cannot
be
deleted.
If
the
"W" bit is set to zero,
the file can be read
r
rom
I
wr itt en to,
0 T'
del e ted ( the
II
D
II
bit
m u s t
b e
zero
also).
The
"W"
bit is one
or
the changeable
attributes of a file.
D (Bit E) -- Delete protection bit
The
"D"
bit only applies to diskette files.
If
this
bit
is set to one,
the file cannot be deleted.
If
the
liD"
bit is
set
to
zero,
the
File
can
be
deleted (the
"W"
bit must be zero also).
The "0"
bit
is one of the changeable attributes of a file.
S (Bit D) -- System file bit
The "S"·bit only applies to diskette files.
If
this
bit is set to one,
the file is considered to be
a system file.
System files
are treated specially by
the
D I R,
DEL,
and
DOSGEN
comma n
d
s .
1 f t he"
S
II
bit
i
s
set to zero,
the file is not a s'jstem file.
The
"sn
bit is one of the changeable attributes of a file.
Page
25-27
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