>The problem under Linux turned out to be that access to the serial port
>was denied to an ordinary user.  But switching over to be root made it
>work.

Aargh. Never do that. If you want to access something that you are not
allowed to normally add its group to your permitted groups and log in
again. Running a potentially buggy program as root, with GUI (not
certified bug-free), with hardware devices attached sounds like, like ...
Windows!

Peter

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