Distinguish between error and "success" in scanimage-batch

I'm running a little script with the scanimage batch-command on a remote server and would like to know if and how the scan has been done the batch. Therefore the script requires a proper "error"-description to handle the next steps. Yet scanimage does return a pretty *odd* message: scanimage: sane_start: Document feeder out of documents So the whole output looks like this if there was a success: scanscript "scanimage --device='brother4:net1;dev0' --format tiff --resolution=150 --source 'Automatic Document Feeder(left aligned,Duplex)' -l 0mm -t 0mm -x210mm -y297mm --batch=$(date +%Y%m%d_%H%M%S)_p%04d.tiff" "/home/qohelet/scans/images/281/" "myscan" scanimage: rounded value of br-x from 210 to 209.981 scanimage: rounded value of br-y from 297 to 296.973 Scanning -1 pages, incrementing by 1, numbering from 1 Scanning page 1 Scanned page 1. (scanner status = 5) Scanning page 2 Scanned page 2. (scanner status = 5) Scanning page 3 scanimage: sane_start: Document feeder out of documents Technically this is correct, yes - but this happens always when the job is done. In case I haven't put any paper into the feeder it looks like that: scanscript "scanimage --device='brother4:net1;dev0' --format tiff --resolution=150 --source 'Automatic Document Feeder(left aligned,Duplex)' -l 0mm -t 0mm -x210mm -y297mm --batch=$(date +%Y%m%d_%H%M%S)_p%04d.tiff" "/home/qohelet/scans/images/281/" "myscan" scanimage: rounded value of br-x from 210 to 209.981 scanimage: rounded value of br-y from 297 to 296.973 Scanning -1 pages, incrementing by 1, numbering from 1 Scanning page 1 scanimage: sane_read: Error during device I/O Scanned page 1. (scanner status = 9) The error 9 is unfortunately just one part of the output. How can I distinguish whether it was thrown or not? In my scanscript I use if to evaluate whether or not the scan was successful: if eval $1; then #Do stuff else #Do error stuff and exit with error code fi Unfortunately when using scanimage with a batch it's always counted as a failure. Is there a way to find out what actually happened? Seems someone had a similar issue with a different scanner (I have a Brother-Scanner, but that's not really related to the issue) already: http://sane.10972.n7.nabble.com/Issue-with-Fujitsu-ScanSnap-iX500-td18589.html But the topic was not continued there, yet now I'm stuck here and would like to know what to do.