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Re: Issues with lseek(2) on a block device



On Sun, Feb 25, 2024 at 04:16:03AM -0000, Michael van Elst wrote:
> tls%panix.com@localhost (Thor Lancelot Simon) writes:
> 
> >Probably not a good idea to start with lseek() because if you _do_
> >encounter a tape device, seeking to SEEK_END could take you an extremely
> >long time.
> 
> lseek() doesn't move the tape. But the open() or close() may trigger
> tape operations like loading or winding. Special files are special.

Ah, yes, that's the MTEOM ioctl -- approximately.

I have it stuck in my mind that SEEK_END did this, too, back when I
was a literal tape jockey for 9 track tapes on an 11/750 and a
collection of TK and QIC-150 drives.  But this could be an invention
of memory.

-- 
  Thor Lancelot Simon	                                     tls%panix.com@localhost

  "The inconsistency is startling, though admittedly, if consistency is to
   be abandoned or transcended, there is no problem."	      - Noam Chomsky


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