It looks like you just need to use some recursion if %hash is of variable structure.

print "<SESSION>\n";
print_hash(\%hash);
print "</SESSION>\n";

sub print_hash {
    my $hashref = shift;
    my $prefix = (@_ ? shift : '') . '  ';

    foreach my $key (sort keys %$hashref) {
        print "$prefix<$key>\n";
        if (ref $hashref->{$key}) {
            print_hash($hashref->{$key}, $prefix);
        } else {
            print "$prefix  $hashref->{$key}\n"
        }
        print "$prefix</$key>\n";
    }
}

[download]

Also, look at package solutions like XML::Simple to do all the xml generation for you.

use XML::Simple;
use strict;
...

print XMLout(\%hash, RootName => 'SESSION');

[download]

Update: Parameter processing updated to avoid warnings.

In reply to Re: Veriable Length Array/Hash derived from CSV to populate an XML by wind
in thread Veriable Length Array/Hash derived from CSV to populate an XML by TheBigAmbulance

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