Everything changed, yes. The button daemon is a quite small program so I expected it to work also with the new system. I was wrong here and now I try to find out why it leaves the system in a state where access to the device is blocked.
Simon > What changed? Just the sane-backends version, or anything else (hardware, > OS, etc) > > allan > > On Wed, Jan 14, 2026 at 2:32 PM Simon Matter <[email protected]> > wrote: > >> I can confirm now that the problem is with the button daemon >> scanmonitord-sanebd only and not with scanimage. >> >> When I run "SANE_DEFAULT_DEVICE=fujitsu:fi-7160:42929 >> scanmonitord-sanebd" >> several times in a terminal and terminate it with Ctrl+C, it will >> suddenly >> say "Open of device fujitsu:fi-7160:42929 failed: Invalid argument". >> While studying the code of scanmonitord-sanebd.c I'm failing to >> understand >> what could be wrong. This has worked fine with SANE backends 1.0.24 but >> something has changed here. >> >> If anyone has an idea what could be wrong, please let me know. I'm quite >> lost here. >> >> Thanks, >> Simon >> >> > I start to believe the problem is not in SANE itself but in the button >> > daemon we are using (see attachement). >> > >> > Our software is running the button daemon and waits for events, then >> > terminates the button daemon and does the appropriate scanimage job, >> and >> > then starts the button daemon again. >> > >> > The button daemon is a modified version of some daemon which was >> floating >> > around many years ago. It has worked well for the last 15 years or so. >> > Maybe there is some modification needed to make it work well with >> newer >> > SANE. >> > >> > If someone who knows SANE better than me would take a look at it, that >> > would be much appreciated. >> > >> > Thanks, >> > Simon >> > >> >> We need to isolate the problem if possible- I expect if you compile >> an >> >> older, known working sane-backends on your current computer, the >> problem >> >> will persist. That would indicate hardware or OS level issue. >> >> >> >> allan >> >> >> >> On Wed, Jan 14, 2026 at 9:35 AM Simon Matter via sane-devel < >> >> [email protected]> wrote: >> >> >> >>> > >> >>> > Hello, >> >>> > >> >>> > On 2026-01-14 14:59, Simon Matter via sane-devel wrote: >> >>> >> These scanners work perfectly fine with very old sane-backends >> >>> >> and operating system. >> >>> > >> >>> > Does it work on the exact same computer >> >>> > where it fails or does it work on old computers? >> >>> >> >>> It works fine on old computers with old software. >> >>> >> >>> > >> >>> > I ask because of possible USB 3 related issues, see >> >>> > https://en.opensuse.org/SDB:Configuring_Scanners#USB >> >>> >> >>> Thanks, I'll check it out. >> >>> >> >>> Simon >> >>> >> >>> >> >>> >> >> >> >> -- >> >> "well, I stand up next to a mountain- and I chop it down with the >> edge >> >> of >> >> my hand" >> >> >> > >> >> >> > > -- > "well, I stand up next to a mountain- and I chop it down with the edge of > my hand" >
