On Tue, 15 Jan 2013 11:31:53 -0500, you wrote: How do you replace a symbol with a new one? IIRC, = with = and == with == $ foo == "one" $ sh sym foo FOO == "one" $ foo = "two" $ sho sym foo FOO = "two" $ foo == "three" $ sho sym foo FOO = "two" $ sho sym foo/global FOO == "three" i.e. one equal sign is for the local symbol, two equal signs are for the global symbol, and the local takes precedence over the global. To delete a symbol: DELETE /SYMBOL HTH, :) G.