<div dir="ltr"><div dir="ltr">On Wed, May 27, 2026 at 1:40\u202fPM Dave McGuire via rescue <<a href="mailto:rescue@sunhelp.org">rescue@sunhelp.org</a>> wrote:<br></div><div class="gmail_quote gmail_quote_container"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On 5/27/26 10:15, Mouse via rescue wrote:<br>
>> It's not an emulator when it's being used as an ordinary mass storage<br>
>> device. When it's configured with a tape device, that *is* an<br>
>> emulation, since it's faking the tape semantics, like move forward,<br>
>> move backward, write tape mark, etc.<br>
> <br>
> Philosophical question, and I mean this as a discussion start rather<br>
> than as anything even vaguely along the lines of "that's wrong!" (if<br>
> for no other reason than that I would use the same terminology):<br>
> <br>
> Why is it emulation when something presents those semantics backed by a<br>
> file on an SD card, but not when backed by rust-coated plastic?<br>
> <br>
> Especially when it's not emulation to present a mass-storage device<br>
> interface regardless of whether it's backed by a file on an SD card or<br>
> rust-coated metal platters?<br>
<br>
SCSI-attached tape uses the SCSI tape command set, which recognizes <br>
the concept of a linear tape that moves back and forth, a sequential <br>
access storage device...and it *moves the tape back and forth*. A <br>
ZuluSCSI implementing tape functionality fakes that sequential behavior <br>
backed by a file on a random-access storage device. That is emulation.<br></blockquote><div><br></div><div>Agreed. I also think emulation is an appropriate term when the underlying thing (SD card, CompactFlash, etc.) has it's own standards and protocols and can be removed from the SCSI emulator and used via its own native interface independent of the emulator. I consider that physical and functional modularity to be definitionally important. If you could remove all the circuits and firmware related to SCSI on a native SCSI block storage device, there's not much you do with the underlying block storage bits and pieces.</div><div><br></div><div>- Nate</div></div></div>