To add to Fletch answer I have ran your code and noticed an error message that array @keys is not declared and you can do this with something as "my @keys;". You could delete the last while loop and save the keys in array @keys. And then cycle through the array like this: 
foreach my $key ( @keys) {
    print $key,"\n";
}

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In reply to Re: Getiing keys or values of a file based hash by zubenel0
in thread Getiing keys or values of a file based hash by shabird

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