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CHAPTER 10
10.
DOSGEN COMMAND
The
DOSGEN command allows specialized MDOS diskettes to
Qe
prepared.
Diskettes that have bad sectors can have
those
sectors
locked
out
so
that the diskette can be used in an
MDOS
environment.
DOSGEN will
also create all system
tables
and
riles on the generated diskette.
The DOSGEN command can
be used to generate system diskettes on
either
single-sided
or appropriately formatted double-sided diskettes.
10. 1
Use
New
single-sided
diskettes,
or
single-sided diskettes
never before used on an MDOS systeml must first
be
prepared
for
use
with MDOS.
One
way
to generate a new MDOS diskette
is by invoking the BACKUP command (Chapter
3);
howevel',
the
BACKUP
command does not perform the
~rite/read
test that can
be invoked via DOSGEN; nor is there the
guarantee
that
all
system files are copied to the destination diskette since the
operator can selectively prevent
files
from
be.ing
copied.
Another
way
to
generate a new
MOOS
diskette is
by
invoking
the
DOSGEN
command
from
an
already
up-and-running
MDOS
system.
DOSGEN·
does
not
create
the
sector
addressing
information.
Single.-sided
diskettes
usually
come
pre-formatted
in
an
IBM-3740-similal'
format
with
the
established
sector
addressing
information.
Double-sided
diskettes,
however,
must be formatted with the FORMAT command
(Chaptel'
15),
since
the
double-sided format
required
by
an
EXDRdisk
I I I
is
a
non-standard single-density format.
In
either
case,
whether
single-
or
double-sided,
other
information
must
be
written
on a new diskette in order to
make it recognizable
by
MOOS.
OOSGEN
creates
the
system
tables
required
by
MDOS
(see
Chapter
24).
These tables
include a skeleton directorYi
a bit map showing which sectors
of the diskette are available for space allocation; a lockout
map showing which sectors of the diskette are bad
or
locked
out
by
the
useri
and an identification sector containing a
name to identiry the diskette,
the generation date,
and
the
MDOS
version
number.
The OOSGEN command also copies across
the required
MDOS
famlly
of
system
files
wnlcn
must
be
present
on any diskette used in the MDOS environment.
These
riles and tables must not be moved
or
changed
in
any
way
other than through the DOSGEN command and two othel' commands:
BACKUP (Chapter
3)
and
REPAIR
(Chapter
22).
Opti-onallYI
th·e
MDOS commands may be copied to the diskette.
Page
10-01
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