I actually was ahead of you and changed to "caller" right after I tried $0, albeit it worked for me, and I was not insisting on robust solution for any and all Perl/OS/hardware combinations.

It came as simple as adding the short standalone subroutine and one line of testing :) 
   standalone() if (!defined caller);  # command-line or "system"

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In reply to Re^6: Dual personality: Module and script by Anonymous Monk
in thread Dual personality: Module and script by Anonymous Monk

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