In addition to unsigned, you could also indicate them as a string, assuming your inputs are strings (as they are in the example you provided). 
printf("%014s", $var1);
printf("%014s", $var2);

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Of course, I can't say for sure that wouldn't cause some other unforeseen issue. just my $0.02

In reply to Re: sprintf zero-fill issue by Anonymous Monk
in thread sprintf zero-fill issue by mlong

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