3/15/72 RF (IV)
NAME rf0 -- RF11-RS11 fixed-head disk file
SYNOPSIS --
DESCRIPTION This file refers to the entire RF disk. It may
be either read or written, although writing is
inherently very dangerous, since a file system
resides there.
The disk contains 1024 256-word blocks, numbered
0 to 1023. Like the other block-structured de-
vices (tape, RK disk) this file is addressed in
blocks, not bytes. This has two consequences:
seek calls refer to block numbers, not byte num-
bers; and sequential reading or writing always
advance the read or write pointer by at least one
block. Thus successive reads of 10 characters
from this file actually read the first 10 charac-
ters from successive blocks.
FILES found in /dev
SEE ALSO tap0(IV), rk0(IV)
DIAGNOSTICS --
BUGS The fact that this device is addressed in terms
of blocks, not bytes, is extremely unfortunate.
It is due entirely to the fact that read and
write pointers (and consequently the arguments to
seek and tell) are single-precision numbers.
This really has to be changed but unfortunately
the repercussions are serious.
OWNER ken, dmr