Try this

#! perl -plw
use strict;
use Win32::Console;
BEGIN{
    my $c=new Win32::Console( STD_ERROR_HANDLE );
    $c->Free();
    $c->Alloc();
}

END{
    print 'Paused'; 1 while sleep 1;
}
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Name that as Errcon.pl and then do

perl -e"open F, '| perl ErrCon.pl' or die $!; print F 'Hello world', $
+_, $/ for 1 .. 100"
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You'll need to use ^Break to end the progam.