Variable Scope

When you create a subprocedure, and you have a global variable,
declared outside of the sub-procedure, and _not_ re-declared inside
the subprocedure, it is my understanding that you can change the value
of the global variable.  Is this true for variables used in the
FILEEXT keyword of F-specs?

I have built a NOMAIN module, with only one sub-procedure defined.  I
have declared a file, with the FILEEXT keyword, specifying a variable.
 This variable is in the D-specs immediately following the F-specs,
before the P-spec.  Inside the P-spec, I have not redefined the
variable used by the FILEEXT keyword.  Inside the subprocedure, When I
eval a qualified filename into the FILEEXT keyword variable, the file
won't open, and I get an error that states it can't find the file
named '          +'.  In debug, after the EVAL op, and before the OPEN
op, the variable contains the filename, but the open fails.  What am I
missing?



-- 
"Enter any 11-digit prime number to continue..."