Using references is a recommended way of passing hashes to subroutines. 
my %hash = (
    foo => "one",
    bar => "two",
    foobar => "three",
);

my %values = func(\%hash);

sub func {
    my $h_ref = shift;
    my %newhash;
    foreach my $key (sort keys %$h_ref) {
        print "$key => ", $h_ref->{$key}, "\n";
        $newhash{$key}=$h_ref->{$key} if $key =~ /regexp/;
    }
    return \%newhash;
}

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In reply to Re: passing paramters to a sub by rupesh
in thread passing paramters to a sub by jimbus

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