[sane-devel] backend integration

Matto Marjanovic maddog@mir.com
Sun, 1 Sep 2002 16:45:08 -0400

 >> Hmm... and the more I look at this, the less I understand what the 
 >>  SANE_STATUS_INVAL case is for.  (The microtek backend is blocking-mode
 >>  exclusively, so I've never really dealt with this....)  What does 
 >>  "image acquistion is pending" mean?  Is that before or after sane_start()
 >>  has been called?
 >sane_set_io_mode must be used after sane_start (and before sane_cancel).

It doesn't seem very intuitive to me, but as long as that is the way it is,
 that should also be explicitly stated in Section 4.3.12 (the description
 of sane_set_io_mode()).

Is the SANE-2 draft online anywhere?  I don't see any link to it on the
 SANE website.  I just got the crazy idea that maybe all of the blocking/
 non-blocking IO mode stuff should be removed from the next version of 
 the standard.  It seems a bit silly and bloated to have so many backends
 re-implementing the same functionality of forking a process to decouple
 their I/O, when it could be written once in the frontend -- especially
 since there are so many more backends than frontends.  This would also
 allow the frontend author to do a much better job of optimizing the flow
 and/or memory useage, since she knows exactly where she wants the data
 to go, and can avoid an extra trip through a pipe, etc.

Just an idea...
-matt m.