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When using nbdsh for scripting, it is convenient to let nbdsh fail with status 1 when encountering an API failure. However, doing so by letting the nbd.Error exception leak all the way causes ABRT (on Fedora 32 at least) to assume the program crashed from a programming error, and needlessly complicates clients to have to add try: blocks. Better is if nbdsh itself prints the same stack trace that