>> with SANE_STATUS_EOF? Will/should the frontend abort the scan, or >> gracefully truncate the output? (Or fill the remaining output with >> black/white?) > >Print a warning and ask the user what to do. Or let the user decide by >preferences.
(What do the current frontends do?) >> I guess another version of my question is: If the backend cannot be >> *certain* that it will deliver 'lines' lines of data, is it required >> to set 'lines' to -1? (Or, can/should it provide the optimistic >> intended image size, which assumes that the paper is long enough?) > >You're speaking about a sheet-fed scanner? I'd use lines = -1 in this >case by default. Maybe add an option "image size" (A4, Legal, >automatic) and use lines = -1 for automatic and a fixed size for the >other settings. Yes --- I'm on the verge of better supporting a sheet-fed Microtek (older) scanner. A user can legitimately specify a fully-defined scan area (upper-left corner, lower-right corner), which is fine if the scan area actually fits on the page they stick into the slot. If not, the backend has to react somehow. I guess it just seems a little odd for the backend to always say 'lines = -1', even if it knows exactly what the line count should/could be (if enough sheet is in there). I'll play around with it, in any case... -matt m.
