Re: [Libguestfs] [libnbd PATCH v2] nbdsh: Catch nbd.Error from -c arguments

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 (at least on Fedora 32 with abrt-python3-handler installed) to assume the program crashed from a programming error, and needlessly complicates clients to have to add try: blocks. Better is if nbdsh itself handles the problem, and only prints a stack trace when debugging is in effect, but otherwise just prints the error message. In this way, the user is not presented with a wall of python stack trace, and ABRT does not think that the exception was unhandled. See https://github.com/libguestfs/nbdkit/commit/e13048fd9 for an example of client cleanup made more verbose if we don't patch libnbd. --- On IRC, we decided that printing the stack trace can be useful when debugging (if -c triggers calls through some deeply-nested python code), but generally gets in the way for default behavior. python/nbdsh.py | 20 ++++++++++++++++---- sh/test-error.sh | 23 ++++++++++++++++++++++- 2 files changed, 38 insertions(+), 5 deletions(-)