I see in my earlier posting that I referred to the fully-qualified variable improperly. I should have said @main::whatever, not main::@whatever. I think that I understand that @main::whatever qualifies it, assuming I'm declaring the value in the 'main' part of the program and not in a subroutine somewhere, for the rest of the program.
If I use it within a subroutine (declaring it first in the 'main' portion of the program), am I correct to understand that I should pass it to the subroutine as subroutine_name(\@main::whatever)?

In any case, here's the answer to your question to me--

Doing:

use strict;
use warnings;

@existingattributes = ();
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Produces the error:

Global symbol "@existingattributes" requires explicit package name at C:\Perl\scripts\configurator.pl line 5.
Execution of C:\Perl\scripts\configurator.pl aborted due to compilation errors.

But perl is happy when I do this:

use strict;
use warnings;

# initialize arrays
@main::existingattributes = ();
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