Page 99 - slides.dvi

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File
Operating
Basic
Other
can
Direct
allow
Systems
Associate
—
indexed
Sequential
a
initialised
forms
Access:
append-only
at
of
read(UFID,
Filesystem
operations:
Operations
implement
cursor
“random”
Access:
read
data
(may
open
sequential
or
buf,
Interface
N
with
read
(II)
be
file
or
access
time
above,
start of file
access
next
access
to
to
or
plus
current
faster)
write
file position
nbytes),
any
position
N
refer
mode
or
seek(UFID,
write
possible,
to
part
already accessed
with
of
e.g.
start
pos)
next,
(ISAM)
each
file.
to be read
of
e.g.
rewind(UFID).
read(UFID,
file.
open
file
buf,
end of file
(viz.
UFID)
nrecords)
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