Restrict EFS to Certain Symbols / Markets

[cv989]

I have done some searching looking to determine if its possible to restrict EFS code to only work with/for certain markets than others. And if this is possible, do all the symbols need defined? or can it be enabled for certain markets IE stocks/futures, etc.

If so how is this possible and what command(s) are used to accomplish this?

I think I am just searching for the incorrect verbage.

Thanks