V4/usr/man/man4/rk.4

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.th RK IV 10/15/73
.sh NAME
rk  \*-  RK-11/RK03 (or RK05) disk
.sh DESCRIPTION
.it Rk?
refers to an entire RK03 disk as a single sequentially-addressed
file.
Its 256-word blocks are numbered 0 to 4871.
.s3
Drive numbers (minor devices)
of eight and greater are treated specially.
Drive 8+\fIx\fR is the \fIx\fR+1 way
interleaving of devices
rk0 to rk\fIx\fR.
Thus blocks on rk10 are distributed alternately
among rk0, rk1, and rk2.
.sh FILES
/dev/rk?
.sh BUGS
Care should be taken in using the interleaved files.
First, the same drive should not be accessed simultaneously
using the ordinary name and as part of an interleaved file,
because the same physical
blocks
have in effect two different
names; this fools the system's buffering strategy.
Second, the combined files cannot be used for swapping.