[sane-devel] Weird behavior in exagear.

[Jeff Sadowski]

Response from brother.

"Hi Jeff.

Any type of sharing feature on a USB model is not supported by
brother. Most questions we received for this are of a Microsoft
nature, but the same policy applies to other OS's as well.

If you are looking to have a machine work on multiple PC's, I
recommend looking into a Network model like MFC-J485DW or something
from the same series."

Hmmm, looks like I need to restate the problem.


On Fri, Jan 12, 2018 at 7:55 AM, Jeff Sadowski <jeff.sadowski at gmail.com> wrote:
> My code is simply calling scanimage the way I posted here already.
> Running the same commands by hand results in the same behaviour. I
> have my code write the command it runs in a file called ran.txt, so I
> can examine it and run it. I'm just using php to open a 3 pipe method
> of running scanimage. it is actually running it under "script" which
> allows scanimage to continually write to stdout/stderr without
> blocking which gets written to a stdout.txt and stderr.txt files. I
> also implemented the ability to send ctrl-c using the 3rd input pipe.
> So if my loop that is reading the pipes sees that a certain file
> exists and is still running it will send a ctrl-c. My frontend starts
> this php script and detaches and then reads it's output files to see
> what is going on it also continually loads the image being created by
> scanimage. I get the latest page number from stdout.txt/stderr.txt and
> the name of the file from my rant.txt looking for '--batch= and the
> matching quote and replace all %d with the last page number and then I
> have my image retrieve send that file. :-)
>
> On Fri, Jan 12, 2018 at 4:07 AM, Olaf Meeuwissen
> <paddy-hack at member.fsf.org> wrote:
>> Hi again,
>>
>> Jeff Sadowski writes:
>>
>>> uning sane -l -d128 -e I am able to see the following error.
>>
>> This
>>
>>> [saned] do_scan: done, status=End of file reached
>>> [saned] process_request: waiting for request
>>> [saned] process_request: bad status 22
>>> [saned] quit: exiting
>>
>> is probably due to the error you get on the other end
>>
>>> scanimage: scanning image of size 1648x2314 pixels at 24 bits/pixel
>>> scanimage: acquiring RGB frame
>>> Progress:98.8%
>>> scanimage: min/max graylevel value = 11/255
>>> Application transferred too few scanlines
>>
>> which indicates that the image acquisition loop ended prematurely for
>> some reason.  While saned will happily continue to serve requests, how
>> the backend and scanner react to this depends on the scanner's firmware
>> and the backend's implementation.  It may very well be that the scanner
>> expects more read requests and refuses to reply to anything else while
>> the backend won't send any of those but instead tries to start a new
>> scan in vain.
>>
>> Based on what you wrote so far, I think this is a bug in the third party
>> brother backend you seem to be using.  The only people that can help you
>> with that are the brother backend developers.  There is nothing the SANE
>> developers can do about it.
>>
>> That said, are you sure *your* code is doing the right thing?  That is,
>> does it read data until sane_read() returns SANE_STATUS_EOF?  Or is it
>> just reading the number of pixels expected based on the results of a
>> sane_get_parameters() before you call sane_start()?  The latter is the
>> *wrong* way to read image data.
>>
>> Hope this helps,
>> --
>> Olaf Meeuwissen, LPIC-2            FSF Associate Member since 2004-01-27
>>  GnuPG key: F84A2DD9/B3C0 2F47 EA19 64F4 9F13  F43E B8A4 A88A F84A 2DD9
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