Everyone has posted good information about regular expressions, so I won't dwell on that. But I will point out that you don't need to use a shell command to get the time. Right now your code reads:

chomp($DATE=`date +%d%b%y`);
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Where the backticks quietly go off and spawn another process to get the date for you. Very slow in comparison to the Perl way: localtime(time); Seeing that you just want the day/month/year, you can do this by saying:

my @date = (localtime(time))[3..5];         # Get the date. (18, 6, 10
+0)
++$date[1] and $date[2] += 1900;            # Make it reader friendly
for( @date[0..1] ){ $_ = "0$_" if 10 > $_ } # Add 0 prefixes as needed
+.
my $DATE = join '', @date;                  # now 18072000
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As usuall, this can be made more tight and efficient, I'm not playing Perl Golf, just showing you don't need to make a shell call to get the date. For more info read perldoc:localtime.