&main;
sub main()
{
	my @mylist = qw(a, b, c);
	foreach(@mylist)
	{
		&fun($_);
		print "changed:\$_ $_\n";
	}
}

sub fun()
{
	my $ret = open(STATUS, "echo d-e-f|");
	while(<STATUS>){
		if(/d-e-f/){
			close(STATUS);
			return;			
		}
	}
	close(STATUS);
}

output not a,b,c:
changed:$_ d-e-f
changed:$_ d-e-f
changed:$_ d-e-f