I recently needed to write some code to pull a single (and first) dn out of each line in an LDAP file. Each dn is contained between '<>' and always begins with capital CN=. I used: 

#!/usr/bin/perl -w
my @dn;
open FILE, "crap" or die $!;
while (<FILE>) {
   chomp $_;
   @dn = $_ =~ /(<CN=.*?>)/;
   print "$dn[0]\n";
}
close (FILE);

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This works great. The only part I'm not sure about is the parenthesis. If I remove them, then I just get in $dn[0] the value 1 which says that yes, the regex was present. By putting the parenthesis in, I instead get the actual match. Could someone give me an explanation for that please?

Thanks!

In reply to Understanding this regex by BradV

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