<s>
DOS	B-Application
XL	I-Application
is	O
a	O
discontinued	O
Disk	B-Operating_System
Operating	I-Operating_System
System	I-Operating_System
(	O
DOS	O
)	O
written	O
by	O
Paul	O
Laughton	O
,	O
Mark	O
Rose	O
,	O
Bill	O
Wilkinson	O
,	O
and	O
Mike	O
Peters	O
and	O
published	O
by	O
Optimized	B-Operating_System
Systems	I-Operating_System
Software	I-Operating_System
(	O
OSS	O
)	O
for	O
the	O
Atari	B-Device
8-bit	I-Device
family	I-Device
of	O
home	O
computers	O
.	O
</s>
<s>
It	O
was	O
designed	O
to	O
be	O
compatible	O
with	O
Atari	B-Operating_System
DOS	I-Operating_System
which	O
came	O
shipped	O
with	O
Atari	O
,	O
Inc.	O
'	O
s	O
disk	O
drives	O
,	O
which	O
had	O
also	O
been	O
written	O
by	O
the	O
same	O
team	O
.	O
</s>
<s>
A	O
direct	O
descendant	O
of	O
OS/A	O
+	O
,	O
DOS	B-Application
XL	I-Application
provided	O
additional	O
features	O
to	O
Atari	O
's	O
equipped	O
with	O
floppy	B-Device
disk	I-Device
drives	I-Device
.	O
</s>
<s>
These	O
included	O
single	O
and	O
double	O
density	O
support	O
,	O
a	O
command-line	B-Application
mode	O
(	O
called	O
the	O
command	O
processor	O
or	O
CP	O
)	O
,	O
a	O
menu	O
mode	O
(	O
an	O
executable	O
loaded	O
in	O
memory	O
)	O
,	O
batch	O
file	O
support	O
,	O
and	O
support	O
for	O
XL	O
extended	O
memory	O
and	O
OSS	O
SuperCartridge	O
banked	O
memory	O
.	O
</s>
<s>
Later	O
versions	O
included	O
Axlon	O
RamDisk	B-Application
support	O
,	O
Mosaic	O
RamDisk	B-Application
support	O
,	O
BIT-3	O
support	O
and	O
BUG/65	O
.	O
</s>
<s>
In	O
addition	O
to	O
supporting	O
auto-booting	O
AUTORUN.SYS	O
files	O
,	O
DOS	B-Application
XL	I-Application
's	O
batch	O
features	O
provided	O
an	O
auto-booting	O
batch	O
feature	O
.	O
</s>
<s>
AtariWriter	B-Protocol
)	O
.	O
</s>
<s>
DOS	B-Application
XL	I-Application
was	O
distributed	O
on	O
a	O
flippy	O
disk	O
.	O
</s>
<s>
The	O
manual	O
for	O
DOS	B-Application
XL	I-Application
was	O
a	O
subset	O
of	O
OS/A	O
+	O
.	O
</s>
<s>
DOS	B-Application
XL	I-Application
came	O
in	O
two	O
versions	O
,	O
2.20	O
and	O
2.30	O
(	O
2.20	O
users	O
had	O
to	O
pay	O
$20	O
to	O
upgrade	O
to	O
2.30	O
)	O
.	O
</s>
<s>
DOS	B-Application
XL	I-Application
originally	O
sold	O
for	O
$30	O
,	O
but	O
the	O
price	O
later	O
increased	O
to	O
$39	O
.	O
</s>
<s>
File	O
writing	O
verify	O
was	O
turned	O
off	O
in	O
DOS	B-Application
XL	I-Application
.	O
</s>
<s>
Atari	B-Operating_System
DOS	I-Operating_System
2.0S	O
by	O
default	O
verified	O
file	O
writes	O
to	O
disk	O
.	O
</s>
<s>
Several	O
disk	O
drive	O
manufacturers	O
shipped	O
DOS	B-Application
XL	I-Application
with	O
their	O
drives	O
:	O
Trak	O
,	O
Percom	O
,	O
Astra	O
,	O
Indus	O
,	O
Amdek	O
,	O
and	O
Rana	O
.	O
</s>
<s>
REN	B-Device
-	O
REName	B-Device
.	O
</s>
<s>
In	O
previous	O
versions	O
of	O
DOS	B-Application
XL	I-Application
,	O
if	O
you	O
initialized	O
a	O
disk	O
from	O
the	O
menu	O
,	O
the	O
disk	O
would	O
not	O
boot	O
unless	O
the	O
file	O
MENU.COM	O
was	O
on	O
the	O
disk	O
.	O
</s>
<s>
The	O
patch	O
for	O
DOS	B-Application
XL	I-Application
2.30	O
to	O
make	O
it	O
a	O
2.30p	O
:	O
</s>
<s>
Plans	O
for	O
DOS	B-Application
XL	I-Application
4	O
were	O
scrapped	O
due	O
to	O
low	O
demand	O
and	O
competition	O
.	O
</s>
<s>
DOS	B-Application
XL	I-Application
,	O
along	O
with	O
other	O
OSS	O
products	O
,	O
became	O
part	O
of	O
ICD	O
's	O
catalog	O
of	O
Atari	O
products	O
in	O
January	O
1988	O
.	O
</s>
<s>
However	O
,	O
DOS	B-Application
XL	I-Application
was	O
dropped	O
in	O
favor	O
of	O
ICD	O
's	O
SpartaDOS	O
.	O
</s>
