On Mon, Mar 28, 2022 at 07:13:13PM +0200, Hans Kurscheidt wrote: > > Am 28.03.2022 um 15:16 schrieb Hans Kurscheidt: > > Hi, > > > > what would be the right mode for gpiomon call from > > > > a shellscript executed as root from systemd at system start > > > > waiting on a Pin w/ pullup for invoking shutdown upon rising* edge. > > *changed > > > > > > Lots of interupts, Signals and other GPIO ongoing from other user APPs & > > threads in multi-user state. > > 2b more precise: I wired a GPIO Pin to GND. > > Upon the cmd: sudo gpiomon -r -n1 <chip> <offset> > > the program exits immediately with 1 event, although there was never a > rising edge due to the fix wire to GND. Is this a feature or a bug, and is > it reproducible? > Not a feature and not reproducible for me on a Raspberry Pi4 with the setup you describe, so probably a bug specific to your hardware platform, whatever that may be. If it is 100% reproduceable for you, and assuming it is an initialisation issue so you only get the one spurious event, how about using -n2 as a workaround ;-)? Cheers, Kent.