I'm working with a small Arm board (Emtrion) running Debian Linux. Emtrion has provided an sdcard image that can update the boards flash. I would like to extend the simple update script, so that when it is finished, it waits for the user to eject the sdcard, and when that happens reboot
. So I'm looking for some simple script mechanism to basically wait for that event. I tried something like:
tail -f -n 1 /var/log/messages | grep -m 1 "card removed"
reboot
My thinking was that I would just troll messages
, and that the -m 1
flag would cause grep
to exit when it found its first match. Alas, that doesn't seem to work, it just keeps going. So I'm hoping there's some other trick/technique I can use. I'm really after something I can do inside of the existing script. I don't have expect
in this image, so that's not an option. It appears to be running busybox
.
udev
? If yes then you can probably hook in to that to be notified when a device is removed, without any log file trolling hacks. – Celada Jul 28 '15 at 22:31udev
. None of the conf files for it seem to exist. I do have an\sbin\mdev
which is a symlink tobusybox
– Travis Griggs Jul 28 '15 at 23:04udev
, it hasmdev
instead. i think this answer might have what you want. – gwillie Jul 28 '15 at 23:58