use strict;
use threads;
use threads::shared;

# pkg cfg
{                     
   package cfg;
    %cfg::thash : shared = ();
}

##</code><code>##

      
use strict;
use threads;
use threads::shared;

# pkg cfg
{                                                     

    package cfg;
    %cfg::thash = ();
    share(%cfg::thash);
}

##</code><code>##

use strict;
use threads;
use threads::shared;

# pkg cfg
{                                                     

    package cfg;
    %cfg::thash = ();
    threads::shared::share(%cfg::thash);
}

##</code><code>##

lock(%cfg::thash);
$v1="A";
$v2="1";
$cfg::thash{$v1}{$v2} ="b";