Hi guys, i have a sample of code in here. can someone please explain to me what does this line below does... (($this_mail) = ($this_in =~ /(.*)/gio)); you may refer to the complete source code i have attached below Thanks in advanced...It's really urgent...can someone please help me!!!! 
#!/usr/bin/perl

# create compare output file for CoIn

use Net::LDAP;
use Net::LDAP::Util qw(ldap_error_name ldap_error_text);
use Encode;

$DEBUG = 2;

$BASEDIR = "/log/sad/info/net/";
$INFILE = "$BASEDIR/test-contacts.dat";
$INFILE = "$BASEDIR/test.dat";
$NOW = `date +%Y%m%d`;
chop ($NOW);
$LOGFILE = "$BASEDIR/DP-contacts-$NOW.txt";

$ldapopts_host = "edsldap.dhl.com:389";
$ldapopts_root = "ou=users,o=dhl.com";

&Main;

sub Main
{
  $conn_in = Net::LDAP->new($ldapopts_host);
  die("server failed $ldapopts_host") unless $conn_in;
  $mesg = $conn_in->bind(dn => $ldapopts_bind,password => $ldapopts_ps
+wd);
  &Debug( 1, "Connected to destination : $ldapopts_host\t$NOW" );

  open( IN, "$INFILE" );
  while( $this_in = <IN> )
  {
    (($this_mail) = ($this_in =~ /(.*)/gio));
    $this_user = $conn_in->search(base => $ldapopts_root, scope => "su
+b", filter => "(|(mail=$this_mail)(mailAlternateAddress=$this_mail))"
+, attr
s => ['uid','mail','mailalternateaddress','cn','ou']);
    &Debug( 3, "Search:(|(mail=$this_mail)(mailAlternateAddress=$this_
+mail))");

    if ($this_user->entries)
    {
      foreach $my_entry ($this_user->entries)
      {
        $entry_uid = $my_entry->get_value('uid');
        $entry_mail = $my_entry->get_value('mail');
        @all_alts = $my_entry->get_value('mailalternateaddress');
        $my_alt_all = "";
        foreach $entry_alt (@all_alts)
        {
          $my_alt_all .= $entry_alt;
          $my_alt_all .= ",";
        }
        chop($my_alt_all);
        $entry_cn = $my_entry->get_value('cn');
        $entry_ou = $my_entry->get_value('ou');
        &Debug( 1, "$entry_ou|$entry_uid|$entry_mail|$my_alt_all|$entr
+y_cn");
      }
    }
     else
    {
      &Debug( 2, "NOT FOUND: $this_mail");
    }
  }
  $conn_in->unbind if $conn_in;
  close(IN);
}

#*****************************
# Handle DEBUG
#*****************************

sub Debug
{
  local( $level, $message ) = @_;

  if( $DEBUG >= $level )
  {
    if( open( DB, ">> $LOGFILE" ) )
    {
      print DB "\t" x ( $level - 1 ), $message, "\n";
      print "\t" x ( $level - 1 ), $message, "\n";
      close( DB );
    };
  };
};

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In reply to Can someone help me to explain the code below by anakin30

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