Comment # 8 on bug 968573 from Dieter Jurzitza

You are totally right. So, my initial procedure was wrong, causing the error
message with the symlink - I guess there were two symlinks at the end of the
day, messing up.

However, I see no way to cope with the modem device on boot but to use a
symlink. If someone switches the connector and reboots, he is currently forced
to reassign the device name in order to restart mgetty on the right device
file.

In contrast, I am determining this device file on boot using hwinfo -modem and
create a symlink based on it's output.

Therefore I would suggest to change mgetty@.service in two regards:

1.) remove the BindsTo entry ...
2.) remove the "dev-%i.device" - string from the "After=" entry.

I even tried to create a device - node using mknod that is called /dev/modem,
pointing to the same device as /dev/ttyS4, having the same major / minor
numbers and the very same permissions, however, mgetty@modem.service did not
work and timed out.

Anyway, thank you for your time - and thank you for correcting my errors, this
was not easy to find.

Take care




Dieter Jurzitza