In <[email protected]>, on 09/06/2012
at 09:11 AM, Charles Mills <[email protected]> said:
>> But don't PDS directory blocks have keys on disk?
>I don't *think* so.
Always has, always will. From z/OS DFSMS Using Data Sets.
SC26-7410-09:
3.7.2 PDS Directory
PDS member entries vary in length and are blocked into 256-byte
blocks.
Each block contains as many complete entries as will fit in a
maximum of
254 bytes. Any remaining bytes are left unused and are ignored.
Each
directory block contains a 2-byte count field that specifies the
number of
active bytes in a block (including the count field). In Figure 110,
each
block is preceded by a hardware-defined key field containing the
name of
the last member entry in the block, that is, the member name with
the
highest binary value. Figure 110 shows the format of the block
returned
when using BSAM to read the directory.
--
Shmuel (Seymour J.) Metz, SysProg and JOAT
Atid/2 <http://patriot.net/~shmuel>
We don't care. We don't have to care, we're Congress.
(S877: The Shut up and Eat Your spam act of 2003)
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