G'day Sriram,

"When i print just $key, it prints outer hash keys,which is correct i.e productnames."

That doesn't seem right. Have you shown the real code you're using or are you incorrectly reporting the behaviour. With:

foreach my $key ( %${hashref} ){
    ....
}
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Printing $key will give you something like:

product name 1
HASH(0xffffffff)
product name 2
HASH(0xffffffff)
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You need to start that loop more like this (i.e. include keys):

for my $key (keys %$hashref) {
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"But,if i want to extract their corresponding inner hash key and values,Output is showing blank."

To print your "inner" values, you'll need to change lines like this

    print $key->{'ProductName'}
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to be more like this

    print $hashref->{$key}{ProductName};
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Another issue is that your subroutine definition, "sub getxml($) {...}", includes a prototype (see "perlsub: Prototypes"). Unless you have a specific reason for using a prototype and really understand why you're using it, I recommend that you remove it, i.e. just use "sub getxml {...}". That's a general recommendation for all of your subroutine definitions, not just this one.

In the previous paragraph I emphasised "really understand why you're using it". I did this because the only call you show to that subroutine, "&getxml($packagehash);", disables prototype checking (which tends to suggest that you don't really understand why you're using it). Again, unless you have a specific reason for doing this and really understand why you're doing it, I recommend that you call your subroutines without a leading ampersand (i.e. in this case, just use getxml($packagehash);). See "perlsub - Perl subroutines" for details.