The swish.cgi description says ....

Features include ........., limiting searches to a subset of documents, 

Does that mean what I hope it means ?
I have indexed a directory say  ./all

One time I  want to search only ./all/a/b/c
another time, I'dlike to search ./all/c/d/e

I was hoping I'd be able to do something like

swish.cgi?subdir=a\/b\/c

and that this would be remembered by the search box presented in the results.

I can't find anything in swish.cgi , i looked in sub default_config

Any ideas ?