warn "dbm_exists" if glob('your_data.{pag,db,dir}');
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There's no promise that this syntax is portable, even to all Unix systems. On versions of Perl prior to 5.6, where glob was a callout to a separate shell process, and a csh-like shell was not available, the Bourne Shell was used, and this would definitely get a Bourne Shell upset.

Of course, now that glob is internal, it's a lot more portable.

-- Randal L. Schwartz, Perl hacker
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