Advertisement
REPAIR COMMAND
22.3 --
Directo~y
Sector Check
22.3 Directory Sector Check
Phase
2
of
REPAIR
deals entirely with
the MDOS
directory
sectors.
Each of the directory sectors is first checked
fo~
readability_
If
a read
error
is
found}
the
operato~
is
informed
and
given
the
choice
of
trying to clear the read
error via the following display:
**FROM IIO ERROR-STATU5=31 AT
2F38
ON DRIVE l-PSN 0013
DIRECTORY SECTOR READ ERROR
WRITE TO DISK TO ATTEMPT TO CLEAR ERROR?
The actual numbers in the error message will
depend
on
the
actual
sector
that
is
in error.
If the operator responds
UJ
i
t han ,; N:; ,
0
or
i
r
the r e
Uil'
i
tea
t
t
em
p
t
(;;
Y ::
1"
e s
p
0
n s e )
r
ail s
to cleaT" the error,
the message
DISK IS NOT FIXABLE
will
be
displayed
and
control
returned
to MDOS.
If the
sectors
are
all
readable,
or
if
the
rewrite
attempt
succeeded,
each
di~ectory
sector
is examined again.
This
time,
each directory
entry
within
each
sector
~s
tested
against the rollowing criteria.
. 1.
If
the. first byte
Or
the directory entry
(unused entry),
then the remaining bytes
entr~
must be zero also.
is lero
of
the
2.
If
the
first byte of the directory entry is the
hex ad e c
i
ma
1
n
u
m
bel'
$FF
<
del e ted en try )
I
the n t h e
second
byte
of
the entry must be $FF also.
If
the
second byte is not
$FF,
and if the
remainder
of
the
entry
is
validJ
then the entry
is
the
result·of an
incomplete
name
change.
It
was
probably
caused
by a power failure or interrupt
(ABORT
or RESTART pushbuttons)
during
the
time
that
the
old
name was deleted and the new name
was added to the directory.
REPAI~
will
allow
the
operator
to
delete
the
directory
entry
entirely or to reassign a name to
the
partially
deleted
entry.
The. name
assigned must be the
same as the original one.
OtherwiseJ
the
name
will
probably
be
improperly
placed
in
the
directory (ci'ite-r-ion
5).
3.
The
physical
sector
number
of
the
Retrieval
Information
Block
must
the
Tirst
sector aT a
cluster, must not be the sector number of one
o~
the
system
tables
checked in Phase
1
or 2, and
must
not
be
greater
than
the
highest
valid
physical sector number.
..../
Page
22-08
Advertisement
