dbmaint pints out a stack trace for file permission problems..

If you try to run dbmaint as a user who doesn't have write permissions to the destination filenames you get the following callstack:

-bash-3.2$ /opt/NorthScale/bin/ep_engine/management/dbmaint --backupto=/tmp
Pausing persistence... paused.
Copying /opt/NorthScale/1.6.0beta3.1/data/ns_1/default-2.sqlite to /tmp/default-2.sqlite
Unpausing persistence.
Traceback (most recent call last):
File "/opt/NorthScale/bin/ep_engine/management/dbmaint", line 62, in ?
main()
File "/opt/NorthScale/bin/ep_engine/management/dbmaint", line 55, in main
shutil.copyfile(fn, dest_fn)
File "/usr/lib64/python2.4/shutil.py", line 48, in copyfile
fdst = open(dst, 'wb')
IOError: [Errno 13] Permission denied: '/tmp/default-2.sqlite'

This should be considered as a "normal" kind of problem and we should just print an error message without the traceback..

See also 2264