zamboni@host			zamboni
zamboni@sub.domain.edu		zamboni
zamboni@sub2.domain.edu		zamboni@sub2
zamboni@something.else.com	zamboni@something.else.com

use Net::Domain qw(hostfqdn);

sub trim_addr {
  # Get the host domain
  my $sbHostname=hostfqdn();
  my @addrs=@_;
  my ($sbHost, $sbSubdomain, $sbDomain)=
    ($sbHostname=~/^([^.]+\.((?:[^.]+\.)?([^.]+\.[^.]+)))$/);
  unless ($sbDomain) {
    die "Could not obtain the local domain from hostname '$sbHostname'
+\n";
  }
  $sbSubdomain=$sbDomain unless $sbSubdomain;
  ($sub=$sbSubdomain)=~s/\.?$sbDomain$//;
  ($host=$sbHost)=~s/\.?$sbSubdomain//;

  foreach (@addrs) {
    s/[@]$sbHost// ||
    s/[@.]$sbSubdomain$// ||
    s/[.]$sbDomain$// ||
    s/[@.]$sub$// ||
    s/[@]$host$//
    ;
  }
  return @addrs;
}
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