1HS(4) Kernel Interfaces Manual HS(4)
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6 hs - RH11/RS03-RS04 fixed-head disk file
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9 The files hs0 ... hs7 refer to RJS03 disk drives 0 through 7. The
10 files hs8 ... hs15 refer to RJS04 disk drives 0 through 7. The RJS03
11 drives are each 1024 blocks long and the RJS04 drives are 2048 blocks
12 long.
13 The hs files access the disk via the system's normal buffering mecha‐
15 nism and may be read and written without regard to physical disk
16 records. There is also a `raw' inteface which provides for direct
17 transmission between the disk and the user's read or write buffer. A
18 single read or write call results in exactly one I/O operation and
19 therefore raw I/O is considerably more efficient when many words are
20 transmitted. The names of the raw HS files begin with rhs. The same
21 minor device considerations hold for the raw interface as for the nor‐
22 mal interface.
23 In raw I/O the buffer must begin on a word boundary, and counts should
25 be a multiple of 512 bytes (a disk block). Likewise lseek calls should
26 specify a multiple of 512 bytes.
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29 /dev/hs?, /dev/rhs?
30 HS(4)