How to use cscope.out that not in the directory of the source code?

I have a source code directory, and I cannot add anything to that directory.

/source/mysource

Then I generate a index db : cscope.out using cscope. Thus I have to save that db in other directories but /source/mysource. If I save that cscope.out in my home directory

~/cscope.out

, how can I tell emacs to get refer开发者_StackOverflow中文版ence to the cscope.out in my home directory?

There is good info here: http://linux.die.net/man/1/xcscope

cscope will automatically look in all parent directories from /source/mysource, but I think the question implies you cannot write to /source

"cscope-initial-directory" does what you need (available from the GUI cscope menu or see the above page for instructions on how to setup a keyboard binding), but you would have to do this for each emacs session.

"cscope-database-regexps" might be an automatic way to do this but I have not tried it.