oops. accidentally hit the 'save' key.. so combining the above with anonymous code.. you can do 
my $req = $mech->click_button(name => 'begin');
$mech->request( $req, '/PATH/TO/SAVED/FILE' );
request method in W::M is an overload of LWP::UserAgent's request method.

In reply to Re^3: WWW:Mechanize click_button stream to file? by Qiang
in thread WWW:Mechanize click_button stream to file? by cormanaz

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