in reply to Tie, DBM's, HoH and Sparse Keys

I tried this (Perl 5.6.1, RedHat 6.0) and found something wierd. 
checkdbm \%terms,$db;
print "hashref =", tied($terms{$db}), "\n";

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prints "hashref =" and the use of uninitialized value warning. So the tiedness of the hash reference is getting lost somewhere.

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Re: Re: Tie, DBM's, HoH and Sparse Keys
by mr.nick (Chaplain) on Apr 11, 2001 at 00:17 UTC
    Yeah, that didn't work quite as expected, so I followed runrigs suggestion and changed it to:
    sub checkdbm {
  my $hashref=shift;
  my $key=shift;
  
  if (-f "$key-dbm.db") {
    return;
  }

  my %hash;

  tie (%hash,'NDBM_File',"$key-dbm",O_RDWR|O_CREAT,0640);

  $hashref->{$key}=\%hash;
}

    [download]
    which works .. sorta. The DB files fill with the correct information, but my memory usage isn't any less. Odd, no?

    Well, off to Storable I suppose (and I was really trying to get THIS to work ... for stubborness sake).

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[d/l]
      If speed is not of the essence...

      Could you try untying the hashes in between operations on particular top-level keys? That should release the NDBM_File buffers and what-not.

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