You may wish to wrap your code in <code> tags next time. I'm not 100% sure what you're asking, but perhaps this code example will answer your question: 
sub function {
   my $hashref = shift;

   $hashref->{three} = 3;
}

my %hash = ( one => 1, two => 2 );
&function(\%hash);
print join(", ", keys %hash);   # one, two, three

[download]
You can also have the same behavior like this: 
sub function (%) {
   my %hashref = shift;
   ...
}

&function(%hash);       # passes %hash as a ref

[download]
Then there's this: 
sub function {
   my %hash = %{shift};   # de-references

   $hash{three} = 3;      # Does not affect the real %hash!
}

[download]

In reply to Re: how do I use a hash of hashes reference to a function ? by Fastolfe
in thread how do I use a hash of hashes reference to a function ? by Anonymous Monk

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