RP(4)               UNIX Programmer's Manual                RP(4)

NAME
     rp - RP-11/RP03 moving-head disk

DESCRIPTION
     Files with minor device numbers 0 through 7 refer to various
     portions of drive 0; minor devices 8 through 15 refer to
     drive 1, etc.  The standard device names begin with ``rp''
     followed by the drive number and then a letter a-h for par-
     titions 0-7 respectively.  The character ? stands here for a
     drive number in the range 0-7.

     The origin and size of the partitions (in 512-byte sectors)
     on each drive are as follows:

     Partitions:
          disk      start     length    cyls      function on drive 0
          rp?a      0         10400     0-51      /
          rp?b      10400     5200      52-77     swap
          rp?c      15600     67580     78-414    /usr
          rp?h      0         83180     0-414     whole pack

     Special files should only be created for the partitions that
     are actually used, as the overlap in these addresses could
     lead to confusion otherwise.

     The block files access the disk via the system's normal
     buffering mechanism and may be read and written without
     regard to physical disk records.  There is also a `raw'
     interface which provides for direct transmission between the
     disk and the user's read or write buffer.  A single read or
     write call results in exactly one I/O operation and there-
     fore raw I/O is considerably more efficient when many words
     are transmitted.  The names of the raw files conventionally
     begin with an extra `r.'

     In raw I/O counts should be a multiple of 512 bytes (a disk
     sector).  Likewise _l_s_e_e_k(2) calls should specify a multiple
     of 512 bytes.

FILES
     /dev/rp[0-7][a-h]   block files
     /dev/rrp[0-7][a-h]  raw files

SEE ALSO
     dvhp(4), hk(4), hp(4), hs(4), ml(4), rf(4), rk(4), rl(4),
     rm(4), rx2(4), xp(4)

DIAGNOSTICS
     rp%d%c: hard error bn %d cs=%b er=%b.  An unrecoverable
     error occured during transfer of the specified sector of the
     specified disk partition.  The contents of the two error
     registers are also printed in octal and symbolically with

Printed 5/17/83                                                 1

RP(4)               UNIX Programmer's Manual                RP(4)

     bits decoded.  The error was either unrecoverable, or a
     large number of retry attempts could not recover the error.

     rp%d: write locked.  The write protect switch was set on the
     drive when a write was attempted.  The write operation is
     not recoverable.

BUGS
     In raw I/O _r_e_a_d and _w_r_i_t_e(2) truncate file offsets to 512-
     byte block boundaries, and _w_r_i_t_e scribbles on the tail of
     incomplete blocks.  Thus, in programs that are likely to
     access raw devices, _r_e_a_d, _w_r_i_t_e and _l_s_e_e_k(2) should always
     deal in 512-byte multiples.

     DEC-standard error logging should be supported.  and this
     would make packs more portable.

Printed 5/17/83                                                 2