SSC-2: obsolete RSMK=0

[Dave Peterson]

* From the T10 Reflector (t10 at t10.org), posted by:
* "Dave Peterson" <dap at cisco.com>
*
Howdy All,

Due to problems that will be encountered when operating with Report
Setmarks=0 (i.e., no setmarks are reported) in explicit address mode, the
tape group is considering a proposal to make RSMK=0 obsolete (for at least
explicit address mode).
In other words, require RSMK=1 and make it non-changeable.

Basic problem items (for explicit address mode) are:
- how to determine the correct logical block address when RSMK=0
- how to determine the correct residual when RSMK=0

Please respond if you feel that obsoleting RSMK=0 (specifically for explicit
address mode) will be a problem.

Note: the editor believes obsoleting RSMK=0 will make life easier (at least
on the editor) for both explicit and implicit address mode operations.

Thanks...dap

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