The Mail::Address and Mail::Header modules can do this task: 

use Mail::Header;
use Mail::Address;

my $header = Mail::Header->new([@lines]);
my($from) = Mail::Address->parse($header->get("From"));
my($user,$host) = ($from->user(),$from->host());

[download]

Edit by tye

In reply to Re: How can I extract the username/domain? by wog
in thread How can I extract the username and hostname/domain from e-mail addresses? by Symuc

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