Can someone help me to explain the code below

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 );
    };
  };
};
[download]

Comment on Can someone help me to explain the code below Download Code
Re: explain code by toolic (Chancellor) on Aug 03, 2010 at 19:21 UTC
Great. You added code tags, but please do not start a new thread. See my other suggestions in: Re: explain code	[reply]
Re: Can someone help me to explain the code below by Anonymous Monk on Aug 03, 2010 at 19:30 UTC
You want to google for "perl regex list context". See: http://perldoc.perl.org/perlretut.html#Extracting-matches	[reply]
Re: Can someone help me to explain the code below by Anonymous Monk on Aug 03, 2010 at 19:59 UTC
`(($this_mail) = ($this_in =~ /(.*)/gio));` That simply matches everything in `$this_in` and assigns it to `$this_mail`. More concisely: `$this_mail = $this_in;`	[reply] [d/l] [select]
Re^2: Can someone help me to explain the code below by anakin30 (Acolyte) on Aug 03, 2010 at 20:05 UTC
thank for your reply.... i have one more question for you...what about this line buddy... ($this_in =~ /(.*)/gio)	[reply]
Re^2: Can someone help me to explain the code below by toolic (Chancellor) on Aug 03, 2010 at 20:08 UTC
. does not match then newline character. So it's more like: `$this_mail = $this_in; chomp $this_mail;` [download]	[reply] [d/l]
Re^3: Can someone help me to explain the code below by anakin30 (Acolyte) on Aug 03, 2010 at 20:16 UTC
($this_mail) and ($this_in) are variable isn't it? but than i didn't see it has been defined in the code? how does it possible? what does the /gio means? , whats the function? ($this_mail) = ($this_in =~ /(.*)/gio)	[reply]
Re^4: Can someone help me to explain the code below by runrig (Abbot) on Aug 03, 2010 at 20:42 UTC
Re^2: Can someone help me to explain the code below by Fletch (Chancellor) on Aug 03, 2010 at 20:54 UTC
When running under `-T` it will also make an untainted copy of the contents of `$this_in` in `$this_mail` (presuming `$this_in` was from a tainted source)</nit> `$ perl -MScalar::Util=tainted -lT -e '($o)=$ENV{PWD}=~/(.)/gio;print +tainted( $_ ) for ( $o, $ENV{PWD} )' 0 1` [download] (Not that that's the case here, but saying it's just a copy assignment isn't universally true . . .) Update:* And before someone else outpedants me, as toolic points out above that should really be "... an untainted copy up to the first newline of the contents ..." :) The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l] [select]
Re^3: Can someone help me to explain the code below by ww (Bishop) on Aug 04, 2010 at 21:11 UTC
Well, true, but <nit> We're untainting only to the extent that we're performing a function that Perl (uncritically) reads as untainting... but without any substantive untainting... In other words, <c>(($this_mail) = ($this_in =~ /(.*)/gio));<c> passes the entire tainted input without any attempt to cull out unacceptable content. </nit> (or is it merely a nit?)	[reply]


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Can someone help me to explain the code below

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