tie (my %hash, 'DB_File', $file, O_RDWR, 0600) || next;
    foreach my $key ( keys %hash ) {

        if (!defined $hash{$key}) {

[download]

The undef value is an internal perl meta-value.    When you store data on an external device (like a tied hash) the undef value is converted to a string, so trying to use defined on this value makes no sense.

In reply to Re: Deleting undefined entries from DB_FILE hash by jwkrahn
in thread Deleting undefined entries from DB_FILE hash by gossamer

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