[sane-devel] [dev] net backend and timing problems? (pretty weird)

mh crapsite@gmx.net
Fri, 7 Sep 2001 06:15:58 +0200


Jochen Eisinger, Don, 06 Sep 2001:
> Hi!
> 
> Does this crash also occur with scanimage? and test?

With scanimage I get this repeatedly until I kill scanimage:
scanimage: stopping scanner... (sig 13) 
This problem *doesn't* occur with the additional sleep().

Running scanimage with the test option reveals nothing (?)

scanimage: scanning image of size 248x150 pixels at 24 bits/pixel
scanimage: acquiring RGB frame, 8 bits/sample
scanimage: reading one scanline, 744 bytes...   PASS
scanimage: reading one byte...          PASS
scanimage: stepped read, 2 bytes...     PASS
scanimage: stepped read, 4 bytes...     PASS
scanimage: stepped read, 8 bytes...     PASS
scanimage: stepped read, 16 bytes...    PASS
scanimage: stepped read, 32 bytes...    PASS
scanimage: stepped read, 64 bytes...    PASS
scanimage: stepped read, 128 bytes...   PASS
scanimage: stepped read, 256 bytes...   PASS
scanimage: stepped read, 512 bytes...   PASS
scanimage: stepped read, 1024 bytes...  PASS
scanimage: stepped read, 1023 bytes...  PASS
scanimage: stepped read, 511 bytes...   PASS
scanimage: stepped read, 255 bytes...   PASS
scanimage: stepped read, 127 bytes...   PASS
scanimage: stepped read, 63 bytes...    PASS
scanimage: stepped read, 31 bytes...    PASS
scanimage: stepped read, 15 bytes...    PASS
scanimage: stepped read, 7 bytes...     PASS
scanimage: stepped read, 3 bytes...     PASS       

Or shorter: I tried this with scanimage,xscanimage,xsane,quiteinsane
withouth sleep(): crashes/problems with every frontend
with sleep(): no crashes, sometimes "error during device I/O" (especially with
xscanimage)

>ahh... and does this happen when using the pnm backend?

Yes, but not with every frontend and not always:
xsane,quiteinsane: Hard to reproduce (but happend in a few cases, IIRC)
xscanimage: happens very often, but not always
scanimage: seems to happen always 

and the same here: no more problems with the additional sleep();
(I tried this at least 100 times with various backend/frontend
combinations -> no crash)

BTW, maybe someone else with the same problem can try to add a sleep() too?
AFAIR, there were a couple of reports about problems with the net backend/saned
on the localhost.

Michael