#!/usr/bin/perl -wT
use strict;

my $calog = "/var/log/ca/ca.log";
my $line;
my @certs;

# open LOG, "$calog" or die "Can't open $calog: $!\n";
while ($line = <DATA>){                      # Switched to  __DATA__ just for example
  if ($line =~ m/\'([-.\w]+)\'\s+added/) {   # Make this Regex a bit smarter
      push(@certs,$1);                       # add the piece in parens above to the @certs array
  } #end if
} #end while

print "$_\n" for @certs;                     # print out the array

__DATA__
Sep 12 17:30:02 nt-ca-na CA(Domain-CA): Certificate name 'jsmith.2048' added to\
 database.
Sep 12 20:09:37 nt-ca-na CA(Domain-CA): Certificate name 'ksmith.2048' added to\
 database.
Sep 12 21:25:30 nt-ca-na CA(Domain-CA): Certificate name 'ssmith.2048' added to\
 database.

=output
jsmith.2048
ksmith.2048
ssmith.2048