If the 'undefined' warning bothers you you can fix it by making sure $tmp2 is always defined. This works wonders: 
my $tmp2 = "";
$tmp2 = $2;

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...which gives you the added bonus of scoping $tmp2. Plus, you don't have to check whether a character is present in your var before substituting it out. 
if($tmp2 =~ m/\'/) {
   $tmp2 =~ s/\'/\\\'/g; # escape the single quotes..
}

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is better written as: 
$tmp2 =~ s/'/\\'/g; # escape the single quotes..

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If there's a single quote in $tmp2 it'll get escaped. Otherwise nothing happens. Note that you don't have to escape single-quotes within a regex.

Lastly if you're paranoid about non-Alphanumerics in your regex's check out the \Q modifier. This does what you want automatically within a regular expression without you having to do anything else.

Gary Blackburn
Trained Killer

Edited:Added my $tmp2=""; to really make $tmp2 defined. :-P

In reply to Re: Use of uninitialized value in pattern match (m//) by Trimbach
in thread Use of uninitialized value in pattern match (m//) by wolis

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