Would it be beyond the realms of possibility for that warning to be produced when a filehandle goes out of scope?
It's a default warning in 5.22.0 onwards: 
$ perl5220 -e'{open my $fh, ">/dev/full"; print $fh "abc"}'
Warning: unable to close filehandle $fh properly: No space left on dev
+ice at -e line 1.
$

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Dave.

In reply to Re^3: forgoing explicit file close by dave_the_m
in thread forgoing explicit file close by fionbarr

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