Hi thanks for suggestion. but i have little doubts.Actually your progran only prints the default values. It does not take the values mentioned by the user in the config file. Suppose the default values are kept in sub routines like 
sub subject {
  'Subject: default subject';
}

sub to {
  'To: default_to@example.com';
}

sub from {
  'From: default_from@example.com';
}

[download]
I could not understand the following syntax, Just give me some hints about it.
my %config = (
  to =>      { regex => '^To:\s', sub => \&to },
  from =>    { regex => '^From:\s', sub => \&from },
  subject => { regex => '^Subject:\s', sub => \&subject },
);

my %cnf;

# Load user data
open DATA,'sss.txt' or die $!;
foreach (<DATA>) {
  chomp;

  foreach my $c (keys %config) {
    if (/$config{$c}{regex}/) {
      $cnf{$c} = $_;
      last;
    }
  }
}

[download]

sss.txt contains
To:sanjay<sanjay@36.212.176.92>
From:sanjay1<sanjay1@36.212.176.90>
Subject:Hi
Actually what i need, if it does not get any value in the config file it will call the sub routines for taking the default values.After that How can i assign the keys and its values in a variable so that i can use that variable for different purpose?

In reply to Re^2: Config file default options? by sanjay nayak
in thread Config file default options? by sanjay nayak

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