Atari 400 Technical Reference Manual page 64

The Disk File Manager can produce the following error statuses:
$03 --
$88 --
$8A-90
$AO
$Al
$A2
$A3
$A4
$A5
$A6
$A7
$A8
SA9
SAA
$AS
Last data from file (EOF on next read).
end-of-file.
-- SIO error set (see Appendix C).
Drive number specification error.
No sector buffer available (too man~ open files).
Disk full.
Fatal 110 error in
director~
or bitmap.
Internal file. mismatch <structural problem).
File name specification erTor.
Point information in error.
File locked to this operation.
Special command invalid.
Director~
full (64 files).
File not found.
Point invalid (file not OPENed for update).
CIO Function Descriptions
The device-specific characteristics of the standard CIO functions
are detailed below:
OPEN FILE
The device name is D. Up to four disk drives can be accessed (D1
through D4). The disk filename can be from 1 to 8 characters in
length with an optional 1- to 3-character extension.
The OPEN FILE command supports the following options:
AUXl
7
o
+-+-+-+-+-+-+-+-+
:WIR: IA:
+-+-+-+-+-+-+-+-+
Where: Wand R are the direction bits.
WR = 00 is invalid
01 indicates OPEN for read
onl~.
10 indicates OPEN for write only.
11 indicates OPEN for read/write (update).
A
=
1 indicates appended output when W
=
1.
You may use these following valid AUXl options:
OPERATING SYSTEM C016555 -- Section 5
79