It seems to me that the -E option, which will write errors to a file, is useless 
(ignored) unless an argument is given.

i.e.,

swish-e -E errfile
is useful

but
swish-e -E
does the same as
swish-e
it just writes errs to stderr.

I'd like to suggest we make the errfile mandatory, just to simplify usage and 
avoid potential confusion.
-- 
Peter Karman  .  http://peknet.com/  .  peter(at)not-real.peknet.com