Typically, you would also know the line number where the error occurs. "Use of uninitialized value in concatenation . . ." would mean that one of the variables in that line is uninitialized. So why not just adding a print statement like 

print STDERR "|\$var1=$var1|\$var2=$var2|\n" unless defined $var1 and 
+defined $var2;

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In reply to Re: trap run time errors by hdb
in thread trap run time errors by kp2a

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